1251883Speter/* 2322444Speter** 2001-09-15 3251883Speter** 4251883Speter** The author disclaims copyright to this source code. In place of 5251883Speter** a legal notice, here is a blessing: 6251883Speter** 7251883Speter** May you do good and not evil. 8251883Speter** May you find forgiveness for yourself and forgive others. 9251883Speter** May you share freely, never taking more than you give. 10251883Speter** 11251883Speter************************************************************************* 12251883Speter** This header file defines the interface that the SQLite library 13251883Speter** presents to client programs. If a C-function, structure, datatype, 14251883Speter** or constant definition does not appear in this file, then it is 15251883Speter** not a published API of SQLite, is subject to change without 16251883Speter** notice, and should not be referenced by programs that use SQLite. 17251883Speter** 18251883Speter** Some of the definitions that are in this file are marked as 19251883Speter** "experimental". Experimental interfaces are normally new 20251883Speter** features recently added to SQLite. We do not anticipate changes 21251883Speter** to experimental interfaces but reserve the right to make minor changes 22251883Speter** if experience from use "in the wild" suggest such changes are prudent. 23251883Speter** 24251883Speter** The official C-language API documentation for SQLite is derived 25251883Speter** from comments in this file. This file is the authoritative source 26286510Speter** on how SQLite interfaces are supposed to operate. 27251883Speter** 28251883Speter** The name of this file under configuration management is "sqlite.h.in". 29251883Speter** The makefile makes some minor changes to this file (such as inserting 30251883Speter** the version number) and changes its name to "sqlite3.h" as 31251883Speter** part of the build process. 32251883Speter*/ 33305002Scy#ifndef SQLITE3_H 34305002Scy#define SQLITE3_H 35251883Speter#include <stdarg.h> /* Needed for the definition of va_list */ 36251883Speter 37251883Speter/* 38251883Speter** Make sure we can call this stuff from C++. 39251883Speter*/ 40251883Speter#ifdef __cplusplus 41251883Speterextern "C" { 42251883Speter#endif 43251883Speter 44251883Speter 45251883Speter/* 46282328Sbapt** Provide the ability to override linkage features of the interface. 47251883Speter*/ 48251883Speter#ifndef SQLITE_EXTERN 49251883Speter# define SQLITE_EXTERN extern 50251883Speter#endif 51251883Speter#ifndef SQLITE_API 52251883Speter# define SQLITE_API 53251883Speter#endif 54282328Sbapt#ifndef SQLITE_CDECL 55282328Sbapt# define SQLITE_CDECL 56282328Sbapt#endif 57305002Scy#ifndef SQLITE_APICALL 58305002Scy# define SQLITE_APICALL 59305002Scy#endif 60282328Sbapt#ifndef SQLITE_STDCALL 61305002Scy# define SQLITE_STDCALL SQLITE_APICALL 62282328Sbapt#endif 63305002Scy#ifndef SQLITE_CALLBACK 64305002Scy# define SQLITE_CALLBACK 65305002Scy#endif 66305002Scy#ifndef SQLITE_SYSAPI 67305002Scy# define SQLITE_SYSAPI 68305002Scy#endif 69251883Speter 70251883Speter/* 71251883Speter** These no-op macros are used in front of interfaces to mark those 72251883Speter** interfaces as either deprecated or experimental. New applications 73282328Sbapt** should not use deprecated interfaces - they are supported for backwards 74251883Speter** compatibility only. Application writers should be aware that 75251883Speter** experimental interfaces are subject to change in point releases. 76251883Speter** 77251883Speter** These macros used to resolve to various kinds of compiler magic that 78251883Speter** would generate warning messages when they were used. But that 79251883Speter** compiler magic ended up generating such a flurry of bug reports 80251883Speter** that we have taken it all out and gone back to using simple 81251883Speter** noop macros. 82251883Speter*/ 83251883Speter#define SQLITE_DEPRECATED 84251883Speter#define SQLITE_EXPERIMENTAL 85251883Speter 86251883Speter/* 87251883Speter** Ensure these symbols were not defined by some previous header file. 88251883Speter*/ 89251883Speter#ifdef SQLITE_VERSION 90251883Speter# undef SQLITE_VERSION 91251883Speter#endif 92251883Speter#ifdef SQLITE_VERSION_NUMBER 93251883Speter# undef SQLITE_VERSION_NUMBER 94251883Speter#endif 95251883Speter 96251883Speter/* 97251883Speter** CAPI3REF: Compile-Time Library Version Numbers 98251883Speter** 99251883Speter** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header 100251883Speter** evaluates to a string literal that is the SQLite version in the 101251883Speter** format "X.Y.Z" where X is the major version number (always 3 for 102251883Speter** SQLite3) and Y is the minor version number and Z is the release number.)^ 103251883Speter** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer 104251883Speter** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same 105251883Speter** numbers used in [SQLITE_VERSION].)^ 106251883Speter** The SQLITE_VERSION_NUMBER for any given release of SQLite will also 107251883Speter** be larger than the release from which it is derived. Either Y will 108251883Speter** be held constant and Z will be incremented or else Y will be incremented 109251883Speter** and Z will be reset to zero. 110251883Speter** 111366076Scy** Since [version 3.6.18] ([dateof:3.6.18]), 112322444Speter** SQLite source code has been stored in the 113251883Speter** <a href="http://www.fossil-scm.org/">Fossil configuration management 114251883Speter** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to 115251883Speter** a string which identifies a particular check-in of SQLite 116251883Speter** within its configuration management system. ^The SQLITE_SOURCE_ID 117322444Speter** string contains the date and time of the check-in (UTC) and a SHA1 118342292Scy** or SHA3-256 hash of the entire source tree. If the source code has 119342292Scy** been edited in any way since it was last checked in, then the last 120342292Scy** four hexadecimal digits of the hash may be modified. 121251883Speter** 122251883Speter** See also: [sqlite3_libversion()], 123251883Speter** [sqlite3_libversion_number()], [sqlite3_sourceid()], 124251883Speter** [sqlite_version()] and [sqlite_source_id()]. 125251883Speter*/ 126369951Scy#define SQLITE_VERSION "3.35.5" 127369951Scy#define SQLITE_VERSION_NUMBER 3035005 128369951Scy#define SQLITE_SOURCE_ID "2021-04-19 18:32:05 1b256d97b553a9611efca188a3d995a2fff712759044ba480f9a0c9e98fae886" 129251883Speter 130251883Speter/* 131251883Speter** CAPI3REF: Run-Time Library Version Numbers 132322444Speter** KEYWORDS: sqlite3_version sqlite3_sourceid 133251883Speter** 134251883Speter** These interfaces provide the same information as the [SQLITE_VERSION], 135251883Speter** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros 136251883Speter** but are associated with the library instead of the header file. ^(Cautious 137251883Speter** programmers might include assert() statements in their application to 138251883Speter** verify that values returned by these interfaces match the macros in 139298161Sbapt** the header, and thus ensure that the application is 140251883Speter** compiled with matching library and header files. 141251883Speter** 142251883Speter** <blockquote><pre> 143251883Speter** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER ); 144342292Scy** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 ); 145251883Speter** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 ); 146251883Speter** </pre></blockquote>)^ 147251883Speter** 148251883Speter** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION] 149251883Speter** macro. ^The sqlite3_libversion() function returns a pointer to the 150251883Speter** to the sqlite3_version[] string constant. The sqlite3_libversion() 151251883Speter** function is provided for use in DLLs since DLL users usually do not have 152251883Speter** direct access to string constants within the DLL. ^The 153251883Speter** sqlite3_libversion_number() function returns an integer equal to 154366076Scy** [SQLITE_VERSION_NUMBER]. ^(The sqlite3_sourceid() function returns 155366076Scy** a pointer to a string constant whose value is the same as the 156342292Scy** [SQLITE_SOURCE_ID] C preprocessor macro. Except if SQLite is built 157342292Scy** using an edited copy of [the amalgamation], then the last four characters 158342292Scy** of the hash might be different from [SQLITE_SOURCE_ID].)^ 159251883Speter** 160251883Speter** See also: [sqlite_version()] and [sqlite_source_id()]. 161251883Speter*/ 162251883SpeterSQLITE_API SQLITE_EXTERN const char sqlite3_version[]; 163322444SpeterSQLITE_API const char *sqlite3_libversion(void); 164322444SpeterSQLITE_API const char *sqlite3_sourceid(void); 165322444SpeterSQLITE_API int sqlite3_libversion_number(void); 166251883Speter 167251883Speter/* 168251883Speter** CAPI3REF: Run-Time Library Compilation Options Diagnostics 169251883Speter** 170366076Scy** ^The sqlite3_compileoption_used() function returns 0 or 1 171366076Scy** indicating whether the specified option was defined at 172366076Scy** compile time. ^The SQLITE_ prefix may be omitted from the 173366076Scy** option name passed to sqlite3_compileoption_used(). 174251883Speter** 175251883Speter** ^The sqlite3_compileoption_get() function allows iterating 176251883Speter** over the list of options that were defined at compile time by 177251883Speter** returning the N-th compile time option string. ^If N is out of range, 178366076Scy** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_ 179366076Scy** prefix is omitted from any strings returned by 180251883Speter** sqlite3_compileoption_get(). 181251883Speter** 182251883Speter** ^Support for the diagnostic functions sqlite3_compileoption_used() 183366076Scy** and sqlite3_compileoption_get() may be omitted by specifying the 184251883Speter** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time. 185251883Speter** 186251883Speter** See also: SQL functions [sqlite_compileoption_used()] and 187251883Speter** [sqlite_compileoption_get()] and the [compile_options pragma]. 188251883Speter*/ 189251883Speter#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS 190322444SpeterSQLITE_API int sqlite3_compileoption_used(const char *zOptName); 191322444SpeterSQLITE_API const char *sqlite3_compileoption_get(int N); 192347347Scy#else 193347347Scy# define sqlite3_compileoption_used(X) 0 194347347Scy# define sqlite3_compileoption_get(X) ((void*)0) 195251883Speter#endif 196251883Speter 197251883Speter/* 198251883Speter** CAPI3REF: Test To See If The Library Is Threadsafe 199251883Speter** 200251883Speter** ^The sqlite3_threadsafe() function returns zero if and only if 201251883Speter** SQLite was compiled with mutexing code omitted due to the 202251883Speter** [SQLITE_THREADSAFE] compile-time option being set to 0. 203251883Speter** 204251883Speter** SQLite can be compiled with or without mutexes. When 205251883Speter** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes 206251883Speter** are enabled and SQLite is threadsafe. When the 207366076Scy** [SQLITE_THREADSAFE] macro is 0, 208251883Speter** the mutexes are omitted. Without the mutexes, it is not safe 209251883Speter** to use SQLite concurrently from more than one thread. 210251883Speter** 211251883Speter** Enabling mutexes incurs a measurable performance penalty. 212251883Speter** So if speed is of utmost importance, it makes sense to disable 213251883Speter** the mutexes. But for maximum safety, mutexes should be enabled. 214251883Speter** ^The default behavior is for mutexes to be enabled. 215251883Speter** 216251883Speter** This interface can be used by an application to make sure that the 217251883Speter** version of SQLite that it is linking against was compiled with 218251883Speter** the desired setting of the [SQLITE_THREADSAFE] macro. 219251883Speter** 220251883Speter** This interface only reports on the compile-time mutex setting 221251883Speter** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with 222251883Speter** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but 223251883Speter** can be fully or partially disabled using a call to [sqlite3_config()] 224251883Speter** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], 225282328Sbapt** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the 226251883Speter** sqlite3_threadsafe() function shows only the compile-time setting of 227251883Speter** thread safety, not any run-time changes to that setting made by 228251883Speter** sqlite3_config(). In other words, the return value from sqlite3_threadsafe() 229251883Speter** is unchanged by calls to sqlite3_config().)^ 230251883Speter** 231251883Speter** See the [threading mode] documentation for additional information. 232251883Speter*/ 233322444SpeterSQLITE_API int sqlite3_threadsafe(void); 234251883Speter 235251883Speter/* 236251883Speter** CAPI3REF: Database Connection Handle 237251883Speter** KEYWORDS: {database connection} {database connections} 238251883Speter** 239251883Speter** Each open SQLite database is represented by a pointer to an instance of 240251883Speter** the opaque structure named "sqlite3". It is useful to think of an sqlite3 241251883Speter** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and 242251883Speter** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] 243251883Speter** and [sqlite3_close_v2()] are its destructors. There are many other 244251883Speter** interfaces (such as 245251883Speter** [sqlite3_prepare_v2()], [sqlite3_create_function()], and 246251883Speter** [sqlite3_busy_timeout()] to name but three) that are methods on an 247251883Speter** sqlite3 object. 248251883Speter*/ 249251883Spetertypedef struct sqlite3 sqlite3; 250251883Speter 251251883Speter/* 252251883Speter** CAPI3REF: 64-Bit Integer Types 253251883Speter** KEYWORDS: sqlite_int64 sqlite_uint64 254251883Speter** 255251883Speter** Because there is no cross-platform way to specify 64-bit integer types 256251883Speter** SQLite includes typedefs for 64-bit signed and unsigned integers. 257251883Speter** 258251883Speter** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. 259251883Speter** The sqlite_int64 and sqlite_uint64 types are supported for backwards 260251883Speter** compatibility only. 261251883Speter** 262251883Speter** ^The sqlite3_int64 and sqlite_int64 types can store integer values 263251883Speter** between -9223372036854775808 and +9223372036854775807 inclusive. ^The 264366076Scy** sqlite3_uint64 and sqlite_uint64 types can store integer values 265251883Speter** between 0 and +18446744073709551615 inclusive. 266251883Speter*/ 267251883Speter#ifdef SQLITE_INT64_TYPE 268251883Speter typedef SQLITE_INT64_TYPE sqlite_int64; 269322444Speter# ifdef SQLITE_UINT64_TYPE 270322444Speter typedef SQLITE_UINT64_TYPE sqlite_uint64; 271366076Scy# else 272322444Speter typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; 273322444Speter# endif 274251883Speter#elif defined(_MSC_VER) || defined(__BORLANDC__) 275251883Speter typedef __int64 sqlite_int64; 276251883Speter typedef unsigned __int64 sqlite_uint64; 277251883Speter#else 278251883Speter typedef long long int sqlite_int64; 279251883Speter typedef unsigned long long int sqlite_uint64; 280251883Speter#endif 281251883Spetertypedef sqlite_int64 sqlite3_int64; 282251883Spetertypedef sqlite_uint64 sqlite3_uint64; 283251883Speter 284251883Speter/* 285251883Speter** If compiling for a processor that lacks floating point support, 286251883Speter** substitute integer for floating-point. 287251883Speter*/ 288251883Speter#ifdef SQLITE_OMIT_FLOATING_POINT 289251883Speter# define double sqlite3_int64 290251883Speter#endif 291251883Speter 292251883Speter/* 293251883Speter** CAPI3REF: Closing A Database Connection 294286510Speter** DESTRUCTOR: sqlite3 295251883Speter** 296251883Speter** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors 297251883Speter** for the [sqlite3] object. 298274884Sbapt** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if 299251883Speter** the [sqlite3] object is successfully destroyed and all associated 300251883Speter** resources are deallocated. 301251883Speter** 302362190Scy** Ideally, applications should [sqlite3_finalize | finalize] all 303366076Scy** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and 304362190Scy** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated 305362190Scy** with the [sqlite3] object prior to attempting to close the object. 306251883Speter** ^If the database connection is associated with unfinalized prepared 307362190Scy** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then 308362190Scy** sqlite3_close() will leave the database connection open and return 309362190Scy** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared 310362190Scy** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups, 311362190Scy** it returns [SQLITE_OK] regardless, but instead of deallocating the database 312362190Scy** connection immediately, it marks the database connection as an unusable 313362190Scy** "zombie" and makes arrangements to automatically deallocate the database 314362190Scy** connection after all prepared statements are finalized, all BLOB handles 315362190Scy** are closed, and all backups have finished. The sqlite3_close_v2() interface 316362190Scy** is intended for use with host languages that are garbage collected, and 317362190Scy** where the order in which destructors are called is arbitrary. 318251883Speter** 319251883Speter** ^If an [sqlite3] object is destroyed while a transaction is open, 320251883Speter** the transaction is automatically rolled back. 321251883Speter** 322251883Speter** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)] 323251883Speter** must be either a NULL 324251883Speter** pointer or an [sqlite3] object pointer obtained 325251883Speter** from [sqlite3_open()], [sqlite3_open16()], or 326251883Speter** [sqlite3_open_v2()], and not previously closed. 327251883Speter** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer 328251883Speter** argument is a harmless no-op. 329251883Speter*/ 330322444SpeterSQLITE_API int sqlite3_close(sqlite3*); 331322444SpeterSQLITE_API int sqlite3_close_v2(sqlite3*); 332251883Speter 333251883Speter/* 334251883Speter** The type for a callback function. 335251883Speter** This is legacy and deprecated. It is included for historical 336251883Speter** compatibility and is not documented. 337251883Speter*/ 338251883Spetertypedef int (*sqlite3_callback)(void*,int,char**, char**); 339251883Speter 340251883Speter/* 341251883Speter** CAPI3REF: One-Step Query Execution Interface 342286510Speter** METHOD: sqlite3 343251883Speter** 344251883Speter** The sqlite3_exec() interface is a convenience wrapper around 345251883Speter** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()], 346251883Speter** that allows an application to run multiple statements of SQL 347366076Scy** without having to use a lot of C code. 348251883Speter** 349251883Speter** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded, 350251883Speter** semicolon-separate SQL statements passed into its 2nd argument, 351251883Speter** in the context of the [database connection] passed in as its 1st 352251883Speter** argument. ^If the callback function of the 3rd argument to 353251883Speter** sqlite3_exec() is not NULL, then it is invoked for each result row 354251883Speter** coming out of the evaluated SQL statements. ^The 4th argument to 355251883Speter** sqlite3_exec() is relayed through to the 1st argument of each 356251883Speter** callback invocation. ^If the callback pointer to sqlite3_exec() 357251883Speter** is NULL, then no callback is ever invoked and result rows are 358251883Speter** ignored. 359251883Speter** 360251883Speter** ^If an error occurs while evaluating the SQL statements passed into 361251883Speter** sqlite3_exec(), then execution of the current statement stops and 362251883Speter** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec() 363251883Speter** is not NULL then any error message is written into memory obtained 364251883Speter** from [sqlite3_malloc()] and passed back through the 5th parameter. 365251883Speter** To avoid memory leaks, the application should invoke [sqlite3_free()] 366251883Speter** on error message strings returned through the 5th parameter of 367298161Sbapt** sqlite3_exec() after the error message string is no longer needed. 368251883Speter** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors 369251883Speter** occur, then sqlite3_exec() sets the pointer in its 5th parameter to 370251883Speter** NULL before returning. 371251883Speter** 372251883Speter** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec() 373251883Speter** routine returns SQLITE_ABORT without invoking the callback again and 374251883Speter** without running any subsequent SQL statements. 375251883Speter** 376251883Speter** ^The 2nd argument to the sqlite3_exec() callback function is the 377251883Speter** number of columns in the result. ^The 3rd argument to the sqlite3_exec() 378251883Speter** callback is an array of pointers to strings obtained as if from 379251883Speter** [sqlite3_column_text()], one for each column. ^If an element of a 380251883Speter** result row is NULL then the corresponding string pointer for the 381251883Speter** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the 382251883Speter** sqlite3_exec() callback is an array of pointers to strings where each 383251883Speter** entry represents the name of corresponding result column as obtained 384251883Speter** from [sqlite3_column_name()]. 385251883Speter** 386251883Speter** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer 387366076Scy** to an empty string, or a pointer that contains only whitespace and/or 388251883Speter** SQL comments, then no SQL statements are evaluated and the database 389251883Speter** is not changed. 390251883Speter** 391251883Speter** Restrictions: 392251883Speter** 393251883Speter** <ul> 394298161Sbapt** <li> The application must ensure that the 1st parameter to sqlite3_exec() 395251883Speter** is a valid and open [database connection]. 396269851Speter** <li> The application must not close the [database connection] specified by 397251883Speter** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running. 398251883Speter** <li> The application must not modify the SQL statement text passed into 399251883Speter** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running. 400251883Speter** </ul> 401251883Speter*/ 402322444SpeterSQLITE_API int sqlite3_exec( 403251883Speter sqlite3*, /* An open database */ 404251883Speter const char *sql, /* SQL to be evaluated */ 405251883Speter int (*callback)(void*,int,char**,char**), /* Callback function */ 406251883Speter void *, /* 1st argument to callback */ 407251883Speter char **errmsg /* Error msg written here */ 408251883Speter); 409251883Speter 410251883Speter/* 411251883Speter** CAPI3REF: Result Codes 412274884Sbapt** KEYWORDS: {result code definitions} 413251883Speter** 414251883Speter** Many SQLite functions return an integer result code from the set shown 415251883Speter** here in order to indicate success or failure. 416251883Speter** 417251883Speter** New error codes may be added in future versions of SQLite. 418251883Speter** 419274884Sbapt** See also: [extended result code definitions] 420251883Speter*/ 421251883Speter#define SQLITE_OK 0 /* Successful result */ 422251883Speter/* beginning-of-error-codes */ 423322444Speter#define SQLITE_ERROR 1 /* Generic error */ 424251883Speter#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ 425251883Speter#define SQLITE_PERM 3 /* Access permission denied */ 426251883Speter#define SQLITE_ABORT 4 /* Callback routine requested an abort */ 427251883Speter#define SQLITE_BUSY 5 /* The database file is locked */ 428251883Speter#define SQLITE_LOCKED 6 /* A table in the database is locked */ 429251883Speter#define SQLITE_NOMEM 7 /* A malloc() failed */ 430251883Speter#define SQLITE_READONLY 8 /* Attempt to write a readonly database */ 431251883Speter#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ 432251883Speter#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ 433251883Speter#define SQLITE_CORRUPT 11 /* The database disk image is malformed */ 434251883Speter#define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */ 435251883Speter#define SQLITE_FULL 13 /* Insertion failed because database is full */ 436251883Speter#define SQLITE_CANTOPEN 14 /* Unable to open the database file */ 437251883Speter#define SQLITE_PROTOCOL 15 /* Database lock protocol error */ 438342292Scy#define SQLITE_EMPTY 16 /* Internal use only */ 439251883Speter#define SQLITE_SCHEMA 17 /* The database schema changed */ 440251883Speter#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ 441251883Speter#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ 442251883Speter#define SQLITE_MISMATCH 20 /* Data type mismatch */ 443251883Speter#define SQLITE_MISUSE 21 /* Library used incorrectly */ 444251883Speter#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ 445251883Speter#define SQLITE_AUTH 23 /* Authorization denied */ 446322444Speter#define SQLITE_FORMAT 24 /* Not used */ 447251883Speter#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ 448251883Speter#define SQLITE_NOTADB 26 /* File opened that is not a database file */ 449251883Speter#define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */ 450251883Speter#define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */ 451251883Speter#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ 452251883Speter#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ 453251883Speter/* end-of-error-codes */ 454251883Speter 455251883Speter/* 456251883Speter** CAPI3REF: Extended Result Codes 457274884Sbapt** KEYWORDS: {extended result code definitions} 458251883Speter** 459274884Sbapt** In its default configuration, SQLite API routines return one of 30 integer 460274884Sbapt** [result codes]. However, experience has shown that many of 461251883Speter** these result codes are too coarse-grained. They do not provide as 462251883Speter** much information about problems as programmers might like. In an effort to 463322444Speter** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8] 464322444Speter** and later) include 465251883Speter** support for additional result codes that provide more detailed information 466274884Sbapt** about errors. These [extended result codes] are enabled or disabled 467251883Speter** on a per database connection basis using the 468274884Sbapt** [sqlite3_extended_result_codes()] API. Or, the extended code for 469274884Sbapt** the most recent error can be obtained using 470274884Sbapt** [sqlite3_extended_errcode()]. 471251883Speter*/ 472342292Scy#define SQLITE_ERROR_MISSING_COLLSEQ (SQLITE_ERROR | (1<<8)) 473342292Scy#define SQLITE_ERROR_RETRY (SQLITE_ERROR | (2<<8)) 474342292Scy#define SQLITE_ERROR_SNAPSHOT (SQLITE_ERROR | (3<<8)) 475251883Speter#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) 476251883Speter#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) 477251883Speter#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) 478251883Speter#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) 479251883Speter#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) 480251883Speter#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) 481251883Speter#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) 482251883Speter#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) 483251883Speter#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) 484251883Speter#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) 485251883Speter#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) 486251883Speter#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) 487251883Speter#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) 488251883Speter#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) 489251883Speter#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) 490251883Speter#define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8)) 491251883Speter#define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8)) 492251883Speter#define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8)) 493251883Speter#define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8)) 494251883Speter#define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8)) 495251883Speter#define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8)) 496251883Speter#define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8)) 497251883Speter#define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8)) 498251883Speter#define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8)) 499269851Speter#define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8)) 500269851Speter#define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8)) 501298161Sbapt#define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8)) 502298161Sbapt#define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8)) 503342292Scy#define SQLITE_IOERR_BEGIN_ATOMIC (SQLITE_IOERR | (29<<8)) 504342292Scy#define SQLITE_IOERR_COMMIT_ATOMIC (SQLITE_IOERR | (30<<8)) 505342292Scy#define SQLITE_IOERR_ROLLBACK_ATOMIC (SQLITE_IOERR | (31<<8)) 506362190Scy#define SQLITE_IOERR_DATA (SQLITE_IOERR | (32<<8)) 507369950Scy#define SQLITE_IOERR_CORRUPTFS (SQLITE_IOERR | (33<<8)) 508251883Speter#define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8)) 509342292Scy#define SQLITE_LOCKED_VTAB (SQLITE_LOCKED | (2<<8)) 510251883Speter#define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8)) 511269851Speter#define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8)) 512362190Scy#define SQLITE_BUSY_TIMEOUT (SQLITE_BUSY | (3<<8)) 513251883Speter#define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8)) 514251883Speter#define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8)) 515251883Speter#define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8)) 516269851Speter#define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8)) 517342292Scy#define SQLITE_CANTOPEN_DIRTYWAL (SQLITE_CANTOPEN | (5<<8)) /* Not Used */ 518361456Scy#define SQLITE_CANTOPEN_SYMLINK (SQLITE_CANTOPEN | (6<<8)) 519251883Speter#define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8)) 520342292Scy#define SQLITE_CORRUPT_SEQUENCE (SQLITE_CORRUPT | (2<<8)) 521362190Scy#define SQLITE_CORRUPT_INDEX (SQLITE_CORRUPT | (3<<8)) 522251883Speter#define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8)) 523251883Speter#define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8)) 524251883Speter#define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8)) 525269851Speter#define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8)) 526342292Scy#define SQLITE_READONLY_CANTINIT (SQLITE_READONLY | (5<<8)) 527342292Scy#define SQLITE_READONLY_DIRECTORY (SQLITE_READONLY | (6<<8)) 528251883Speter#define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8)) 529251883Speter#define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8)) 530251883Speter#define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8)) 531251883Speter#define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8)) 532251883Speter#define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8)) 533251883Speter#define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8)) 534251883Speter#define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8)) 535251883Speter#define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8)) 536251883Speter#define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8)) 537251883Speter#define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8)) 538269851Speter#define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8)) 539361456Scy#define SQLITE_CONSTRAINT_PINNED (SQLITE_CONSTRAINT |(11<<8)) 540251883Speter#define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8)) 541251883Speter#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8)) 542269851Speter#define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8)) 543274884Sbapt#define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8)) 544305002Scy#define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8)) 545361456Scy#define SQLITE_OK_SYMLINK (SQLITE_OK | (2<<8)) 546251883Speter 547251883Speter/* 548251883Speter** CAPI3REF: Flags For File Open Operations 549251883Speter** 550251883Speter** These bit values are intended for use in the 551251883Speter** 3rd parameter to the [sqlite3_open_v2()] interface and 552251883Speter** in the 4th parameter to the [sqlite3_vfs.xOpen] method. 553251883Speter*/ 554251883Speter#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */ 555251883Speter#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */ 556251883Speter#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */ 557251883Speter#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */ 558251883Speter#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */ 559251883Speter#define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */ 560251883Speter#define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */ 561251883Speter#define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */ 562251883Speter#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */ 563251883Speter#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */ 564251883Speter#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */ 565251883Speter#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */ 566251883Speter#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */ 567251883Speter#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */ 568366076Scy#define SQLITE_OPEN_SUPER_JOURNAL 0x00004000 /* VFS only */ 569251883Speter#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */ 570251883Speter#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */ 571251883Speter#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */ 572251883Speter#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */ 573251883Speter#define SQLITE_OPEN_WAL 0x00080000 /* VFS only */ 574361456Scy#define SQLITE_OPEN_NOFOLLOW 0x01000000 /* Ok for sqlite3_open_v2() */ 575251883Speter 576251883Speter/* Reserved: 0x00F00000 */ 577366076Scy/* Legacy compatibility: */ 578366076Scy#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */ 579251883Speter 580366076Scy 581251883Speter/* 582251883Speter** CAPI3REF: Device Characteristics 583251883Speter** 584251883Speter** The xDeviceCharacteristics method of the [sqlite3_io_methods] 585251883Speter** object returns an integer which is a vector of these 586251883Speter** bit values expressing I/O characteristics of the mass storage 587251883Speter** device that holds the file that the [sqlite3_io_methods] 588251883Speter** refers to. 589251883Speter** 590251883Speter** The SQLITE_IOCAP_ATOMIC property means that all writes of 591251883Speter** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 592251883Speter** mean that writes of blocks that are nnn bytes in size and 593251883Speter** are aligned to an address which is an integer multiple of 594251883Speter** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 595251883Speter** that when data is appended to a file, the data is appended 596251883Speter** first then the size of the file is extended, never the other 597251883Speter** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 598251883Speter** information is written to disk in the same order as calls 599251883Speter** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that 600251883Speter** after reboot following a crash or power loss, the only bytes in a 601251883Speter** file that were written at the application level might have changed 602251883Speter** and that adjacent bytes, even bytes within the same sector are 603269851Speter** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 604322444Speter** flag indicates that a file cannot be deleted when open. The 605269851Speter** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on 606269851Speter** read-only media and cannot be changed even by processes with 607269851Speter** elevated privileges. 608342292Scy** 609342292Scy** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying 610342292Scy** filesystem supports doing multiple write operations atomically when those 611342292Scy** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and 612342292Scy** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. 613251883Speter*/ 614251883Speter#define SQLITE_IOCAP_ATOMIC 0x00000001 615251883Speter#define SQLITE_IOCAP_ATOMIC512 0x00000002 616251883Speter#define SQLITE_IOCAP_ATOMIC1K 0x00000004 617251883Speter#define SQLITE_IOCAP_ATOMIC2K 0x00000008 618251883Speter#define SQLITE_IOCAP_ATOMIC4K 0x00000010 619251883Speter#define SQLITE_IOCAP_ATOMIC8K 0x00000020 620251883Speter#define SQLITE_IOCAP_ATOMIC16K 0x00000040 621251883Speter#define SQLITE_IOCAP_ATOMIC32K 0x00000080 622251883Speter#define SQLITE_IOCAP_ATOMIC64K 0x00000100 623251883Speter#define SQLITE_IOCAP_SAFE_APPEND 0x00000200 624251883Speter#define SQLITE_IOCAP_SEQUENTIAL 0x00000400 625251883Speter#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800 626251883Speter#define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000 627269851Speter#define SQLITE_IOCAP_IMMUTABLE 0x00002000 628342292Scy#define SQLITE_IOCAP_BATCH_ATOMIC 0x00004000 629251883Speter 630251883Speter/* 631251883Speter** CAPI3REF: File Locking Levels 632251883Speter** 633251883Speter** SQLite uses one of these integer values as the second 634251883Speter** argument to calls it makes to the xLock() and xUnlock() methods 635251883Speter** of an [sqlite3_io_methods] object. 636251883Speter*/ 637251883Speter#define SQLITE_LOCK_NONE 0 638251883Speter#define SQLITE_LOCK_SHARED 1 639251883Speter#define SQLITE_LOCK_RESERVED 2 640251883Speter#define SQLITE_LOCK_PENDING 3 641251883Speter#define SQLITE_LOCK_EXCLUSIVE 4 642251883Speter 643251883Speter/* 644251883Speter** CAPI3REF: Synchronization Type Flags 645251883Speter** 646251883Speter** When SQLite invokes the xSync() method of an 647251883Speter** [sqlite3_io_methods] object it uses a combination of 648251883Speter** these integer values as the second argument. 649251883Speter** 650251883Speter** When the SQLITE_SYNC_DATAONLY flag is used, it means that the 651251883Speter** sync operation only needs to flush data to mass storage. Inode 652251883Speter** information need not be flushed. If the lower four bits of the flag 653251883Speter** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics. 654251883Speter** If the lower four bits equal SQLITE_SYNC_FULL, that means 655251883Speter** to use Mac OS X style fullsync instead of fsync(). 656251883Speter** 657251883Speter** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags 658251883Speter** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL 659251883Speter** settings. The [synchronous pragma] determines when calls to the 660251883Speter** xSync VFS method occur and applies uniformly across all platforms. 661251883Speter** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how 662251883Speter** energetic or rigorous or forceful the sync operations are and 663251883Speter** only make a difference on Mac OSX for the default SQLite code. 664251883Speter** (Third-party VFS implementations might also make the distinction 665251883Speter** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the 666251883Speter** operating systems natively supported by SQLite, only Mac OSX 667251883Speter** cares about the difference.) 668251883Speter*/ 669251883Speter#define SQLITE_SYNC_NORMAL 0x00002 670251883Speter#define SQLITE_SYNC_FULL 0x00003 671251883Speter#define SQLITE_SYNC_DATAONLY 0x00010 672251883Speter 673251883Speter/* 674251883Speter** CAPI3REF: OS Interface Open File Handle 675251883Speter** 676366076Scy** An [sqlite3_file] object represents an open file in the 677251883Speter** [sqlite3_vfs | OS interface layer]. Individual OS interface 678251883Speter** implementations will 679251883Speter** want to subclass this object by appending additional fields 680251883Speter** for their own use. The pMethods entry is a pointer to an 681251883Speter** [sqlite3_io_methods] object that defines methods for performing 682251883Speter** I/O operations on the open file. 683251883Speter*/ 684251883Spetertypedef struct sqlite3_file sqlite3_file; 685251883Speterstruct sqlite3_file { 686251883Speter const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ 687251883Speter}; 688251883Speter 689251883Speter/* 690251883Speter** CAPI3REF: OS Interface File Virtual Methods Object 691251883Speter** 692251883Speter** Every file opened by the [sqlite3_vfs.xOpen] method populates an 693251883Speter** [sqlite3_file] object (or, more commonly, a subclass of the 694251883Speter** [sqlite3_file] object) with a pointer to an instance of this object. 695251883Speter** This object defines the methods used to perform various operations 696251883Speter** against the open file represented by the [sqlite3_file] object. 697251883Speter** 698366076Scy** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element 699251883Speter** to a non-NULL pointer, then the sqlite3_io_methods.xClose method 700251883Speter** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The 701251883Speter** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen] 702251883Speter** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element 703251883Speter** to NULL. 704251883Speter** 705251883Speter** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or 706251883Speter** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). 707251883Speter** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY] 708251883Speter** flag may be ORed in to indicate that only the data of the file 709251883Speter** and not its inode needs to be synced. 710251883Speter** 711251883Speter** The integer values to xLock() and xUnlock() are one of 712251883Speter** <ul> 713251883Speter** <li> [SQLITE_LOCK_NONE], 714251883Speter** <li> [SQLITE_LOCK_SHARED], 715251883Speter** <li> [SQLITE_LOCK_RESERVED], 716251883Speter** <li> [SQLITE_LOCK_PENDING], or 717251883Speter** <li> [SQLITE_LOCK_EXCLUSIVE]. 718251883Speter** </ul> 719251883Speter** xLock() increases the lock. xUnlock() decreases the lock. 720251883Speter** The xCheckReservedLock() method checks whether any database connection, 721251883Speter** either in this process or in some other process, is holding a RESERVED, 722251883Speter** PENDING, or EXCLUSIVE lock on the file. It returns true 723251883Speter** if such a lock exists and false otherwise. 724251883Speter** 725251883Speter** The xFileControl() method is a generic interface that allows custom 726251883Speter** VFS implementations to directly control an open file using the 727251883Speter** [sqlite3_file_control()] interface. The second "op" argument is an 728251883Speter** integer opcode. The third argument is a generic pointer intended to 729251883Speter** point to a structure that may contain arguments or space in which to 730251883Speter** write return values. Potential uses for xFileControl() might be 731251883Speter** functions to enable blocking locks with timeouts, to change the 732251883Speter** locking strategy (for example to use dot-file locks), to inquire 733251883Speter** about the status of a lock, or to break stale locks. The SQLite 734251883Speter** core reserves all opcodes less than 100 for its own use. 735274884Sbapt** A [file control opcodes | list of opcodes] less than 100 is available. 736251883Speter** Applications that define a custom xFileControl method should use opcodes 737251883Speter** greater than 100 to avoid conflicts. VFS implementations should 738251883Speter** return [SQLITE_NOTFOUND] for file control opcodes that they do not 739251883Speter** recognize. 740251883Speter** 741251883Speter** The xSectorSize() method returns the sector size of the 742251883Speter** device that underlies the file. The sector size is the 743251883Speter** minimum write that can be performed without disturbing 744251883Speter** other bytes in the file. The xDeviceCharacteristics() 745251883Speter** method returns a bit vector describing behaviors of the 746251883Speter** underlying device: 747251883Speter** 748251883Speter** <ul> 749251883Speter** <li> [SQLITE_IOCAP_ATOMIC] 750251883Speter** <li> [SQLITE_IOCAP_ATOMIC512] 751251883Speter** <li> [SQLITE_IOCAP_ATOMIC1K] 752251883Speter** <li> [SQLITE_IOCAP_ATOMIC2K] 753251883Speter** <li> [SQLITE_IOCAP_ATOMIC4K] 754251883Speter** <li> [SQLITE_IOCAP_ATOMIC8K] 755251883Speter** <li> [SQLITE_IOCAP_ATOMIC16K] 756251883Speter** <li> [SQLITE_IOCAP_ATOMIC32K] 757251883Speter** <li> [SQLITE_IOCAP_ATOMIC64K] 758251883Speter** <li> [SQLITE_IOCAP_SAFE_APPEND] 759251883Speter** <li> [SQLITE_IOCAP_SEQUENTIAL] 760322444Speter** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN] 761322444Speter** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE] 762322444Speter** <li> [SQLITE_IOCAP_IMMUTABLE] 763342292Scy** <li> [SQLITE_IOCAP_BATCH_ATOMIC] 764251883Speter** </ul> 765251883Speter** 766251883Speter** The SQLITE_IOCAP_ATOMIC property means that all writes of 767251883Speter** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 768251883Speter** mean that writes of blocks that are nnn bytes in size and 769251883Speter** are aligned to an address which is an integer multiple of 770251883Speter** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 771251883Speter** that when data is appended to a file, the data is appended 772251883Speter** first then the size of the file is extended, never the other 773251883Speter** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 774251883Speter** information is written to disk in the same order as calls 775251883Speter** to xWrite(). 776251883Speter** 777251883Speter** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill 778251883Speter** in the unread portions of the buffer with zeros. A VFS that 779251883Speter** fails to zero-fill short reads might seem to work. However, 780251883Speter** failure to zero-fill short reads will eventually lead to 781251883Speter** database corruption. 782251883Speter*/ 783251883Spetertypedef struct sqlite3_io_methods sqlite3_io_methods; 784251883Speterstruct sqlite3_io_methods { 785251883Speter int iVersion; 786251883Speter int (*xClose)(sqlite3_file*); 787251883Speter int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); 788251883Speter int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); 789251883Speter int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); 790251883Speter int (*xSync)(sqlite3_file*, int flags); 791251883Speter int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); 792251883Speter int (*xLock)(sqlite3_file*, int); 793251883Speter int (*xUnlock)(sqlite3_file*, int); 794251883Speter int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); 795251883Speter int (*xFileControl)(sqlite3_file*, int op, void *pArg); 796251883Speter int (*xSectorSize)(sqlite3_file*); 797251883Speter int (*xDeviceCharacteristics)(sqlite3_file*); 798251883Speter /* Methods above are valid for version 1 */ 799251883Speter int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**); 800251883Speter int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); 801251883Speter void (*xShmBarrier)(sqlite3_file*); 802251883Speter int (*xShmUnmap)(sqlite3_file*, int deleteFlag); 803251883Speter /* Methods above are valid for version 2 */ 804251883Speter int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp); 805251883Speter int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p); 806251883Speter /* Methods above are valid for version 3 */ 807251883Speter /* Additional methods may be added in future releases */ 808251883Speter}; 809251883Speter 810251883Speter/* 811251883Speter** CAPI3REF: Standard File Control Opcodes 812274884Sbapt** KEYWORDS: {file control opcodes} {file control opcode} 813251883Speter** 814251883Speter** These integer constants are opcodes for the xFileControl method 815251883Speter** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] 816251883Speter** interface. 817251883Speter** 818282328Sbapt** <ul> 819282328Sbapt** <li>[[SQLITE_FCNTL_LOCKSTATE]] 820251883Speter** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This 821251883Speter** opcode causes the xFileControl method to write the current state of 822251883Speter** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], 823251883Speter** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) 824251883Speter** into an integer that the pArg argument points to. This capability 825282328Sbapt** is used during testing and is only available when the SQLITE_TEST 826282328Sbapt** compile-time option is used. 827282328Sbapt** 828251883Speter** <li>[[SQLITE_FCNTL_SIZE_HINT]] 829251883Speter** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS 830251883Speter** layer a hint of how large the database file will grow to be during the 831251883Speter** current transaction. This hint is not guaranteed to be accurate but it 832251883Speter** is often close. The underlying VFS might choose to preallocate database 833251883Speter** file space based on this hint in order to help writes to the database 834251883Speter** file run faster. 835251883Speter** 836346442Scy** <li>[[SQLITE_FCNTL_SIZE_LIMIT]] 837346442Scy** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that 838346442Scy** implements [sqlite3_deserialize()] to set an upper bound on the size 839346442Scy** of the in-memory database. The argument is a pointer to a [sqlite3_int64]. 840346442Scy** If the integer pointed to is negative, then it is filled in with the 841346442Scy** current limit. Otherwise the limit is set to the larger of the value 842346442Scy** of the integer pointed to and the current database size. The integer 843346442Scy** pointed to is set to the new limit. 844346442Scy** 845251883Speter** <li>[[SQLITE_FCNTL_CHUNK_SIZE]] 846251883Speter** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS 847251883Speter** extends and truncates the database file in chunks of a size specified 848366076Scy** by the user. The fourth argument to [sqlite3_file_control()] should 849251883Speter** point to an integer (type int) containing the new chunk-size to use 850251883Speter** for the nominated database. Allocating database file space in large 851251883Speter** chunks (say 1MB at a time), may reduce file-system fragmentation and 852251883Speter** improve performance on some systems. 853251883Speter** 854251883Speter** <li>[[SQLITE_FCNTL_FILE_POINTER]] 855251883Speter** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer 856251883Speter** to the [sqlite3_file] object associated with a particular database 857298161Sbapt** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER]. 858251883Speter** 859298161Sbapt** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]] 860298161Sbapt** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer 861298161Sbapt** to the [sqlite3_file] object associated with the journal file (either 862298161Sbapt** the [rollback journal] or the [write-ahead log]) for a particular database 863298161Sbapt** connection. See also [SQLITE_FCNTL_FILE_POINTER]. 864298161Sbapt** 865251883Speter** <li>[[SQLITE_FCNTL_SYNC_OMITTED]] 866269851Speter** No longer in use. 867251883Speter** 868269851Speter** <li>[[SQLITE_FCNTL_SYNC]] 869269851Speter** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and 870269851Speter** sent to the VFS immediately before the xSync method is invoked on a 871366076Scy** database file descriptor. Or, if the xSync method is not invoked 872366076Scy** because the user has configured SQLite with 873366076Scy** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place 874269851Speter** of the xSync method. In most cases, the pointer argument passed with 875269851Speter** this file-control is NULL. However, if the database file is being synced 876269851Speter** as part of a multi-database commit, the argument points to a nul-terminated 877366076Scy** string containing the transactions super-journal file name. VFSes that 878366076Scy** do not need this signal should silently ignore this opcode. Applications 879366076Scy** should not call [sqlite3_file_control()] with this opcode as doing so may 880366076Scy** disrupt the operation of the specialized VFSes that do require it. 881269851Speter** 882269851Speter** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]] 883269851Speter** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite 884269851Speter** and sent to the VFS after a transaction has been committed immediately 885269851Speter** but before the database is unlocked. VFSes that do not need this signal 886269851Speter** should silently ignore this opcode. Applications should not call 887366076Scy** [sqlite3_file_control()] with this opcode as doing so may disrupt the 888366076Scy** operation of the specialized VFSes that do require it. 889269851Speter** 890251883Speter** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]] 891251883Speter** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic 892251883Speter** retry counts and intervals for certain disk I/O operations for the 893251883Speter** windows [VFS] in order to provide robustness in the presence of 894251883Speter** anti-virus programs. By default, the windows VFS will retry file read, 895251883Speter** file write, and file delete operations up to 10 times, with a delay 896251883Speter** of 25 milliseconds before the first retry and with the delay increasing 897251883Speter** by an additional 25 milliseconds with each subsequent retry. This 898251883Speter** opcode allows these two values (10 retries and 25 milliseconds of delay) 899251883Speter** to be adjusted. The values are changed for all database connections 900251883Speter** within the same process. The argument is a pointer to an array of two 901322444Speter** integers where the first integer is the new retry count and the second 902251883Speter** integer is the delay. If either integer is negative, then the setting 903251883Speter** is not changed but instead the prior value of that setting is written 904251883Speter** into the array entry, allowing the current retry settings to be 905251883Speter** interrogated. The zDbName parameter is ignored. 906251883Speter** 907251883Speter** <li>[[SQLITE_FCNTL_PERSIST_WAL]] 908251883Speter** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the 909251883Speter** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary 910342292Scy** write ahead log ([WAL file]) and shared memory 911342292Scy** files used for transaction control 912251883Speter** are automatically deleted when the latest connection to the database 913251883Speter** closes. Setting persistent WAL mode causes those files to persist after 914251883Speter** close. Persisting the files is useful when other processes that do not 915251883Speter** have write permission on the directory containing the database file want 916251883Speter** to read the database file, as the WAL and shared memory files must exist 917251883Speter** in order for the database to be readable. The fourth parameter to 918251883Speter** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 919251883Speter** That integer is 0 to disable persistent WAL mode or 1 to enable persistent 920251883Speter** WAL mode. If the integer is -1, then it is overwritten with the current 921251883Speter** WAL persistence setting. 922251883Speter** 923251883Speter** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]] 924251883Speter** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the 925251883Speter** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting 926251883Speter** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the 927251883Speter** xDeviceCharacteristics methods. The fourth parameter to 928251883Speter** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 929251883Speter** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage 930251883Speter** mode. If the integer is -1, then it is overwritten with the current 931251883Speter** zero-damage mode setting. 932251883Speter** 933251883Speter** <li>[[SQLITE_FCNTL_OVERWRITE]] 934251883Speter** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening 935251883Speter** a write transaction to indicate that, unless it is rolled back for some 936366076Scy** reason, the entire database file will be overwritten by the current 937251883Speter** transaction. This is used by VACUUM operations. 938251883Speter** 939251883Speter** <li>[[SQLITE_FCNTL_VFSNAME]] 940251883Speter** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of 941251883Speter** all [VFSes] in the VFS stack. The names are of all VFS shims and the 942366076Scy** final bottom-level VFS are written into memory obtained from 943251883Speter** [sqlite3_malloc()] and the result is stored in the char* variable 944251883Speter** that the fourth parameter of [sqlite3_file_control()] points to. 945251883Speter** The caller is responsible for freeing the memory when done. As with 946251883Speter** all file-control actions, there is no guarantee that this will actually 947251883Speter** do anything. Callers should initialize the char* variable to a NULL 948251883Speter** pointer in case this file-control is not implemented. This file-control 949251883Speter** is intended for diagnostic use only. 950251883Speter** 951298161Sbapt** <li>[[SQLITE_FCNTL_VFS_POINTER]] 952298161Sbapt** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level 953298161Sbapt** [VFSes] currently in use. ^(The argument X in 954298161Sbapt** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be 955298161Sbapt** of type "[sqlite3_vfs] **". This opcodes will set *X 956298161Sbapt** to a pointer to the top-level VFS.)^ 957298161Sbapt** ^When there are multiple VFS shims in the stack, this opcode finds the 958298161Sbapt** upper-most shim only. 959298161Sbapt** 960251883Speter** <li>[[SQLITE_FCNTL_PRAGMA]] 961366076Scy** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] 962251883Speter** file control is sent to the open [sqlite3_file] object corresponding 963251883Speter** to the database file to which the pragma statement refers. ^The argument 964251883Speter** to the [SQLITE_FCNTL_PRAGMA] file control is an array of 965251883Speter** pointers to strings (char**) in which the second element of the array 966251883Speter** is the name of the pragma and the third element is the argument to the 967251883Speter** pragma or NULL if the pragma has no argument. ^The handler for an 968251883Speter** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element 969251883Speter** of the char** argument point to a string obtained from [sqlite3_mprintf()] 970251883Speter** or the equivalent and that string will become the result of the pragma or 971251883Speter** the error message if the pragma fails. ^If the 972366076Scy** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal 973251883Speter** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA] 974251883Speter** file control returns [SQLITE_OK], then the parser assumes that the 975251883Speter** VFS has handled the PRAGMA itself and the parser generates a no-op 976282328Sbapt** prepared statement if result string is NULL, or that returns a copy 977282328Sbapt** of the result string if the string is non-NULL. 978282328Sbapt** ^If the [SQLITE_FCNTL_PRAGMA] file control returns 979251883Speter** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means 980251883Speter** that the VFS encountered an error while handling the [PRAGMA] and the 981251883Speter** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA] 982251883Speter** file control occurs at the beginning of pragma statement analysis and so 983251883Speter** it is able to override built-in [PRAGMA] statements. 984251883Speter** 985251883Speter** <li>[[SQLITE_FCNTL_BUSYHANDLER]] 986251883Speter** ^The [SQLITE_FCNTL_BUSYHANDLER] 987251883Speter** file-control may be invoked by SQLite on the database file handle 988251883Speter** shortly after it is opened in order to provide a custom VFS with access 989361456Scy** to the connection's busy-handler callback. The argument is of type (void**) 990251883Speter** - an array of two (void *) values. The first (void *) actually points 991361456Scy** to a function of type (int (*)(void *)). In order to invoke the connection's 992251883Speter** busy-handler, this function should be invoked with the second (void *) in 993251883Speter** the array as the only argument. If it returns non-zero, then the operation 994251883Speter** should be retried. If it returns zero, the custom VFS should abandon the 995251883Speter** current operation. 996251883Speter** 997251883Speter** <li>[[SQLITE_FCNTL_TEMPFILENAME]] 998361456Scy** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control 999251883Speter** to have SQLite generate a 1000251883Speter** temporary filename using the same algorithm that is followed to generate 1001251883Speter** temporary filenames for TEMP tables and other internal uses. The 1002251883Speter** argument should be a char** which will be filled with the filename 1003251883Speter** written into memory obtained from [sqlite3_malloc()]. The caller should 1004251883Speter** invoke [sqlite3_free()] on the result to avoid a memory leak. 1005251883Speter** 1006251883Speter** <li>[[SQLITE_FCNTL_MMAP_SIZE]] 1007251883Speter** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the 1008251883Speter** maximum number of bytes that will be used for memory-mapped I/O. 1009251883Speter** The argument is a pointer to a value of type sqlite3_int64 that 1010251883Speter** is an advisory maximum number of bytes in the file to memory map. The 1011251883Speter** pointer is overwritten with the old value. The limit is not changed if 1012366076Scy** the value originally pointed to is negative, and so the current limit 1013251883Speter** can be queried by passing in a pointer to a negative number. This 1014251883Speter** file-control is used internally to implement [PRAGMA mmap_size]. 1015251883Speter** 1016269851Speter** <li>[[SQLITE_FCNTL_TRACE]] 1017269851Speter** The [SQLITE_FCNTL_TRACE] file control provides advisory information 1018269851Speter** to the VFS about what the higher layers of the SQLite stack are doing. 1019269851Speter** This file control is used by some VFS activity tracing [shims]. 1020269851Speter** The argument is a zero-terminated string. Higher layers in the 1021269851Speter** SQLite stack may generate instances of this file control if 1022269851Speter** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled. 1023269851Speter** 1024269851Speter** <li>[[SQLITE_FCNTL_HAS_MOVED]] 1025269851Speter** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a 1026269851Speter** pointer to an integer and it writes a boolean into that integer depending 1027269851Speter** on whether or not the file has been renamed, moved, or deleted since it 1028269851Speter** was first opened. 1029269851Speter** 1030322444Speter** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]] 1031322444Speter** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the 1032322444Speter** underlying native file handle associated with a file handle. This file 1033322444Speter** control interprets its argument as a pointer to a native file handle and 1034322444Speter** writes the resulting value there. 1035322444Speter** 1036269851Speter** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]] 1037269851Speter** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This 1038269851Speter** opcode causes the xFileControl method to swap the file handle with the one 1039269851Speter** pointed to by the pArg argument. This capability is used during testing 1040269851Speter** and only needs to be supported when SQLITE_TEST is defined. 1041269851Speter** 1042282328Sbapt** <li>[[SQLITE_FCNTL_WAL_BLOCK]] 1043282328Sbapt** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might 1044282328Sbapt** be advantageous to block on the next WAL lock if the lock is not immediately 1045282328Sbapt** available. The WAL subsystem issues this signal during rare 1046282328Sbapt** circumstances in order to fix a problem with priority inversion. 1047282328Sbapt** Applications should <em>not</em> use this file-control. 1048282328Sbapt** 1049286510Speter** <li>[[SQLITE_FCNTL_ZIPVFS]] 1050286510Speter** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other 1051286510Speter** VFS should return SQLITE_NOTFOUND for this opcode. 1052286510Speter** 1053286510Speter** <li>[[SQLITE_FCNTL_RBU]] 1054286510Speter** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by 1055286510Speter** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for 1056366076Scy** this opcode. 1057342292Scy** 1058342292Scy** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]] 1059342292Scy** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then 1060342292Scy** the file descriptor is placed in "batch write mode", which 1061342292Scy** means all subsequent write operations will be deferred and done 1062342292Scy** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. Systems 1063342292Scy** that do not support batch atomic writes will return SQLITE_NOTFOUND. 1064342292Scy** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to 1065342292Scy** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or 1066342292Scy** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make 1067342292Scy** no VFS interface calls on the same [sqlite3_file] file descriptor 1068342292Scy** except for calls to the xWrite method and the xFileControl method 1069342292Scy** with [SQLITE_FCNTL_SIZE_HINT]. 1070342292Scy** 1071342292Scy** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]] 1072342292Scy** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write 1073366076Scy** operations since the previous successful call to 1074342292Scy** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically. 1075342292Scy** This file control returns [SQLITE_OK] if and only if the writes were 1076342292Scy** all performed successfully and have been committed to persistent storage. 1077342292Scy** ^Regardless of whether or not it is successful, this file control takes 1078342292Scy** the file descriptor out of batch write mode so that all subsequent 1079342292Scy** write operations are independent. 1080342292Scy** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without 1081342292Scy** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. 1082342292Scy** 1083342292Scy** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]] 1084342292Scy** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write 1085366076Scy** operations since the previous successful call to 1086342292Scy** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back. 1087342292Scy** ^This file control takes the file descriptor out of batch write mode 1088342292Scy** so that all subsequent write operations are independent. 1089342292Scy** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without 1090342292Scy** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. 1091342292Scy** 1092342292Scy** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]] 1093362190Scy** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS 1094366076Scy** to block for up to M milliseconds before failing when attempting to 1095366076Scy** obtain a file lock using the xLock or xShmLock methods of the VFS. 1096362190Scy** The parameter is a pointer to a 32-bit signed integer that contains 1097362190Scy** the value that M is to be set to. Before returning, the 32-bit signed 1098362190Scy** integer is overwritten with the previous value of M. 1099342292Scy** 1100342292Scy** <li>[[SQLITE_FCNTL_DATA_VERSION]] 1101342292Scy** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to 1102342292Scy** a database file. The argument is a pointer to a 32-bit unsigned integer. 1103342292Scy** The "data version" for the pager is written into the pointer. The 1104342292Scy** "data version" changes whenever any change occurs to the corresponding 1105342292Scy** database file, either through SQL statements on the same database 1106342292Scy** connection or through transactions committed by separate database 1107342292Scy** connections possibly in other processes. The [sqlite3_total_changes()] 1108342292Scy** interface can be used to find if any database on the connection has changed, 1109342292Scy** but that interface responds to changes on TEMP as well as MAIN and does 1110342292Scy** not provide a mechanism to detect changes to MAIN only. Also, the 1111342292Scy** [sqlite3_total_changes()] interface responds to internal changes only and 1112342292Scy** omits changes made by other database connections. The 1113361456Scy** [PRAGMA data_version] command provides a mechanism to detect changes to 1114342292Scy** a single attached database that occur due to other database connections, 1115342292Scy** but omits changes implemented by the database connection on which it is 1116342292Scy** called. This file control is the only mechanism to detect changes that 1117342292Scy** happen either internally or externally and that are associated with 1118342292Scy** a particular attached database. 1119361456Scy** 1120362190Scy** <li>[[SQLITE_FCNTL_CKPT_START]] 1121362190Scy** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint 1122362190Scy** in wal mode before the client starts to copy pages from the wal 1123362190Scy** file to the database file. 1124362190Scy** 1125361456Scy** <li>[[SQLITE_FCNTL_CKPT_DONE]] 1126361456Scy** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint 1127361456Scy** in wal mode after the client has finished copying pages from the wal 1128361456Scy** file to the database file, but before the *-shm file is updated to 1129361456Scy** record the fact that the pages have been checkpointed. 1130251883Speter** </ul> 1131251883Speter*/ 1132251883Speter#define SQLITE_FCNTL_LOCKSTATE 1 1133282328Sbapt#define SQLITE_FCNTL_GET_LOCKPROXYFILE 2 1134282328Sbapt#define SQLITE_FCNTL_SET_LOCKPROXYFILE 3 1135282328Sbapt#define SQLITE_FCNTL_LAST_ERRNO 4 1136251883Speter#define SQLITE_FCNTL_SIZE_HINT 5 1137251883Speter#define SQLITE_FCNTL_CHUNK_SIZE 6 1138251883Speter#define SQLITE_FCNTL_FILE_POINTER 7 1139251883Speter#define SQLITE_FCNTL_SYNC_OMITTED 8 1140251883Speter#define SQLITE_FCNTL_WIN32_AV_RETRY 9 1141251883Speter#define SQLITE_FCNTL_PERSIST_WAL 10 1142251883Speter#define SQLITE_FCNTL_OVERWRITE 11 1143251883Speter#define SQLITE_FCNTL_VFSNAME 12 1144251883Speter#define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13 1145251883Speter#define SQLITE_FCNTL_PRAGMA 14 1146251883Speter#define SQLITE_FCNTL_BUSYHANDLER 15 1147251883Speter#define SQLITE_FCNTL_TEMPFILENAME 16 1148251883Speter#define SQLITE_FCNTL_MMAP_SIZE 18 1149269851Speter#define SQLITE_FCNTL_TRACE 19 1150269851Speter#define SQLITE_FCNTL_HAS_MOVED 20 1151269851Speter#define SQLITE_FCNTL_SYNC 21 1152269851Speter#define SQLITE_FCNTL_COMMIT_PHASETWO 22 1153269851Speter#define SQLITE_FCNTL_WIN32_SET_HANDLE 23 1154282328Sbapt#define SQLITE_FCNTL_WAL_BLOCK 24 1155286510Speter#define SQLITE_FCNTL_ZIPVFS 25 1156286510Speter#define SQLITE_FCNTL_RBU 26 1157298161Sbapt#define SQLITE_FCNTL_VFS_POINTER 27 1158298161Sbapt#define SQLITE_FCNTL_JOURNAL_POINTER 28 1159322444Speter#define SQLITE_FCNTL_WIN32_GET_HANDLE 29 1160322444Speter#define SQLITE_FCNTL_PDB 30 1161342292Scy#define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE 31 1162342292Scy#define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE 32 1163342292Scy#define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE 33 1164342292Scy#define SQLITE_FCNTL_LOCK_TIMEOUT 34 1165342292Scy#define SQLITE_FCNTL_DATA_VERSION 35 1166346442Scy#define SQLITE_FCNTL_SIZE_LIMIT 36 1167361456Scy#define SQLITE_FCNTL_CKPT_DONE 37 1168362190Scy#define SQLITE_FCNTL_RESERVE_BYTES 38 1169362190Scy#define SQLITE_FCNTL_CKPT_START 39 1170251883Speter 1171282328Sbapt/* deprecated names */ 1172282328Sbapt#define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE 1173282328Sbapt#define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE 1174282328Sbapt#define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO 1175282328Sbapt 1176282328Sbapt 1177251883Speter/* 1178251883Speter** CAPI3REF: Mutex Handle 1179251883Speter** 1180251883Speter** The mutex module within SQLite defines [sqlite3_mutex] to be an 1181251883Speter** abstract type for a mutex object. The SQLite core never looks 1182251883Speter** at the internal representation of an [sqlite3_mutex]. It only 1183251883Speter** deals with pointers to the [sqlite3_mutex] object. 1184251883Speter** 1185251883Speter** Mutexes are created using [sqlite3_mutex_alloc()]. 1186251883Speter*/ 1187251883Spetertypedef struct sqlite3_mutex sqlite3_mutex; 1188251883Speter 1189251883Speter/* 1190305002Scy** CAPI3REF: Loadable Extension Thunk 1191305002Scy** 1192305002Scy** A pointer to the opaque sqlite3_api_routines structure is passed as 1193305002Scy** the third parameter to entry points of [loadable extensions]. This 1194305002Scy** structure must be typedefed in order to work around compiler warnings 1195305002Scy** on some platforms. 1196305002Scy*/ 1197305002Scytypedef struct sqlite3_api_routines sqlite3_api_routines; 1198305002Scy 1199305002Scy/* 1200251883Speter** CAPI3REF: OS Interface Object 1201251883Speter** 1202251883Speter** An instance of the sqlite3_vfs object defines the interface between 1203251883Speter** the SQLite core and the underlying operating system. The "vfs" 1204251883Speter** in the name of the object stands for "virtual file system". See 1205251883Speter** the [VFS | VFS documentation] for further information. 1206251883Speter** 1207342292Scy** The VFS interface is sometimes extended by adding new methods onto 1208342292Scy** the end. Each time such an extension occurs, the iVersion field 1209342292Scy** is incremented. The iVersion value started out as 1 in 1210342292Scy** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2 1211342292Scy** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased 1212342292Scy** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields 1213342292Scy** may be appended to the sqlite3_vfs object and the iVersion value 1214342292Scy** may increase again in future versions of SQLite. 1215361456Scy** Note that due to an oversight, the structure 1216361456Scy** of the sqlite3_vfs object changed in the transition from 1217342292Scy** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0] 1218361456Scy** and yet the iVersion field was not increased. 1219251883Speter** 1220251883Speter** The szOsFile field is the size of the subclassed [sqlite3_file] 1221251883Speter** structure used by this VFS. mxPathname is the maximum length of 1222251883Speter** a pathname in this VFS. 1223251883Speter** 1224251883Speter** Registered sqlite3_vfs objects are kept on a linked list formed by 1225251883Speter** the pNext pointer. The [sqlite3_vfs_register()] 1226251883Speter** and [sqlite3_vfs_unregister()] interfaces manage this list 1227251883Speter** in a thread-safe way. The [sqlite3_vfs_find()] interface 1228251883Speter** searches the list. Neither the application code nor the VFS 1229251883Speter** implementation should use the pNext pointer. 1230251883Speter** 1231251883Speter** The pNext field is the only field in the sqlite3_vfs 1232251883Speter** structure that SQLite will ever modify. SQLite will only access 1233251883Speter** or modify this field while holding a particular static mutex. 1234251883Speter** The application should never modify anything within the sqlite3_vfs 1235251883Speter** object once the object has been registered. 1236251883Speter** 1237251883Speter** The zName field holds the name of the VFS module. The name must 1238251883Speter** be unique across all VFS modules. 1239251883Speter** 1240251883Speter** [[sqlite3_vfs.xOpen]] 1241251883Speter** ^SQLite guarantees that the zFilename parameter to xOpen 1242251883Speter** is either a NULL pointer or string obtained 1243251883Speter** from xFullPathname() with an optional suffix added. 1244251883Speter** ^If a suffix is added to the zFilename parameter, it will 1245251883Speter** consist of a single "-" character followed by no more than 1246251883Speter** 11 alphanumeric and/or "-" characters. 1247251883Speter** ^SQLite further guarantees that 1248251883Speter** the string will be valid and unchanged until xClose() is 1249251883Speter** called. Because of the previous sentence, 1250251883Speter** the [sqlite3_file] can safely store a pointer to the 1251251883Speter** filename if it needs to remember the filename for some reason. 1252251883Speter** If the zFilename parameter to xOpen is a NULL pointer then xOpen 1253366076Scy** must invent its own temporary name for the file. ^Whenever the 1254251883Speter** xFilename parameter is NULL it will also be the case that the 1255251883Speter** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. 1256251883Speter** 1257251883Speter** The flags argument to xOpen() includes all bits set in 1258251883Speter** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] 1259251883Speter** or [sqlite3_open16()] is used, then flags includes at least 1260366076Scy** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. 1261251883Speter** If xOpen() opens a file read-only then it sets *pOutFlags to 1262251883Speter** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. 1263251883Speter** 1264251883Speter** ^(SQLite will also add one of the following flags to the xOpen() 1265251883Speter** call, depending on the object being opened: 1266251883Speter** 1267251883Speter** <ul> 1268251883Speter** <li> [SQLITE_OPEN_MAIN_DB] 1269251883Speter** <li> [SQLITE_OPEN_MAIN_JOURNAL] 1270251883Speter** <li> [SQLITE_OPEN_TEMP_DB] 1271251883Speter** <li> [SQLITE_OPEN_TEMP_JOURNAL] 1272251883Speter** <li> [SQLITE_OPEN_TRANSIENT_DB] 1273251883Speter** <li> [SQLITE_OPEN_SUBJOURNAL] 1274366076Scy** <li> [SQLITE_OPEN_SUPER_JOURNAL] 1275251883Speter** <li> [SQLITE_OPEN_WAL] 1276251883Speter** </ul>)^ 1277251883Speter** 1278251883Speter** The file I/O implementation can use the object type flags to 1279251883Speter** change the way it deals with files. For example, an application 1280251883Speter** that does not care about crash recovery or rollback might make 1281251883Speter** the open of a journal file a no-op. Writes to this journal would 1282251883Speter** also be no-ops, and any attempt to read the journal would return 1283251883Speter** SQLITE_IOERR. Or the implementation might recognize that a database 1284251883Speter** file will be doing page-aligned sector reads and writes in a random 1285251883Speter** order and set up its I/O subsystem accordingly. 1286251883Speter** 1287251883Speter** SQLite might also add one of the following flags to the xOpen method: 1288251883Speter** 1289251883Speter** <ul> 1290251883Speter** <li> [SQLITE_OPEN_DELETEONCLOSE] 1291251883Speter** <li> [SQLITE_OPEN_EXCLUSIVE] 1292251883Speter** </ul> 1293251883Speter** 1294251883Speter** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be 1295251883Speter** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE] 1296251883Speter** will be set for TEMP databases and their journals, transient 1297251883Speter** databases, and subjournals. 1298251883Speter** 1299251883Speter** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction 1300251883Speter** with the [SQLITE_OPEN_CREATE] flag, which are both directly 1301251883Speter** analogous to the O_EXCL and O_CREAT flags of the POSIX open() 1302366076Scy** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 1303251883Speter** SQLITE_OPEN_CREATE, is used to indicate that file should always 1304251883Speter** be created, and that it is an error if it already exists. 1305366076Scy** It is <i>not</i> used to indicate the file should be opened 1306251883Speter** for exclusive access. 1307251883Speter** 1308251883Speter** ^At least szOsFile bytes of memory are allocated by SQLite 1309361456Scy** to hold the [sqlite3_file] structure passed as the third 1310251883Speter** argument to xOpen. The xOpen method does not have to 1311251883Speter** allocate the structure; it should just fill it in. Note that 1312251883Speter** the xOpen method must set the sqlite3_file.pMethods to either 1313251883Speter** a valid [sqlite3_io_methods] object or to NULL. xOpen must do 1314251883Speter** this even if the open fails. SQLite expects that the sqlite3_file.pMethods 1315251883Speter** element will be valid after xOpen returns regardless of the success 1316251883Speter** or failure of the xOpen call. 1317251883Speter** 1318251883Speter** [[sqlite3_vfs.xAccess]] 1319251883Speter** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] 1320251883Speter** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to 1321251883Speter** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] 1322351633Scy** to test whether a file is at least readable. The SQLITE_ACCESS_READ 1323351633Scy** flag is never actually used and is not implemented in the built-in 1324351633Scy** VFSes of SQLite. The file is named by the second argument and can be a 1325351633Scy** directory. The xAccess method returns [SQLITE_OK] on success or some 1326351633Scy** non-zero error code if there is an I/O error or if the name of 1327351633Scy** the file given in the second argument is illegal. If SQLITE_OK 1328351633Scy** is returned, then non-zero or zero is written into *pResOut to indicate 1329366076Scy** whether or not the file is accessible. 1330251883Speter** 1331251883Speter** ^SQLite will always allocate at least mxPathname+1 bytes for the 1332251883Speter** output buffer xFullPathname. The exact size of the output buffer 1333251883Speter** is also passed as a parameter to both methods. If the output buffer 1334251883Speter** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is 1335251883Speter** handled as a fatal error by SQLite, vfs implementations should endeavor 1336251883Speter** to prevent this by setting mxPathname to a sufficiently large value. 1337251883Speter** 1338251883Speter** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64() 1339251883Speter** interfaces are not strictly a part of the filesystem, but they are 1340251883Speter** included in the VFS structure for completeness. 1341251883Speter** The xRandomness() function attempts to return nBytes bytes 1342251883Speter** of good-quality randomness into zOut. The return value is 1343251883Speter** the actual number of bytes of randomness obtained. 1344251883Speter** The xSleep() method causes the calling thread to sleep for at 1345251883Speter** least the number of microseconds given. ^The xCurrentTime() 1346251883Speter** method returns a Julian Day Number for the current date and time as 1347251883Speter** a floating point value. 1348251883Speter** ^The xCurrentTimeInt64() method returns, as an integer, the Julian 1349366076Scy** Day Number multiplied by 86400000 (the number of milliseconds in 1350366076Scy** a 24-hour day). 1351251883Speter** ^SQLite will use the xCurrentTimeInt64() method to get the current 1352366076Scy** date and time if that method is available (if iVersion is 2 or 1353251883Speter** greater and the function pointer is not NULL) and will fall back 1354251883Speter** to xCurrentTime() if xCurrentTimeInt64() is unavailable. 1355251883Speter** 1356251883Speter** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces 1357251883Speter** are not used by the SQLite core. These optional interfaces are provided 1358366076Scy** by some VFSes to facilitate testing of the VFS code. By overriding 1359251883Speter** system calls with functions under its control, a test program can 1360251883Speter** simulate faults and error conditions that would otherwise be difficult 1361251883Speter** or impossible to induce. The set of system calls that can be overridden 1362251883Speter** varies from one VFS to another, and from one version of the same VFS to the 1363251883Speter** next. Applications that use these interfaces must be prepared for any 1364251883Speter** or all of these interfaces to be NULL or for their behavior to change 1365251883Speter** from one release to the next. Applications must not attempt to access 1366251883Speter** any of these methods if the iVersion of the VFS is less than 3. 1367251883Speter*/ 1368251883Spetertypedef struct sqlite3_vfs sqlite3_vfs; 1369251883Spetertypedef void (*sqlite3_syscall_ptr)(void); 1370251883Speterstruct sqlite3_vfs { 1371251883Speter int iVersion; /* Structure version number (currently 3) */ 1372251883Speter int szOsFile; /* Size of subclassed sqlite3_file */ 1373251883Speter int mxPathname; /* Maximum file pathname length */ 1374251883Speter sqlite3_vfs *pNext; /* Next registered VFS */ 1375251883Speter const char *zName; /* Name of this virtual file system */ 1376251883Speter void *pAppData; /* Pointer to application-specific data */ 1377251883Speter int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*, 1378251883Speter int flags, int *pOutFlags); 1379251883Speter int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); 1380251883Speter int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); 1381251883Speter int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); 1382251883Speter void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); 1383251883Speter void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); 1384251883Speter void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void); 1385251883Speter void (*xDlClose)(sqlite3_vfs*, void*); 1386251883Speter int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); 1387251883Speter int (*xSleep)(sqlite3_vfs*, int microseconds); 1388251883Speter int (*xCurrentTime)(sqlite3_vfs*, double*); 1389251883Speter int (*xGetLastError)(sqlite3_vfs*, int, char *); 1390251883Speter /* 1391251883Speter ** The methods above are in version 1 of the sqlite_vfs object 1392251883Speter ** definition. Those that follow are added in version 2 or later 1393251883Speter */ 1394251883Speter int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*); 1395251883Speter /* 1396251883Speter ** The methods above are in versions 1 and 2 of the sqlite_vfs object. 1397251883Speter ** Those below are for version 3 and greater. 1398251883Speter */ 1399251883Speter int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr); 1400251883Speter sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName); 1401251883Speter const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName); 1402251883Speter /* 1403251883Speter ** The methods above are in versions 1 through 3 of the sqlite_vfs object. 1404298161Sbapt ** New fields may be appended in future versions. The iVersion 1405366076Scy ** value will increment whenever this happens. 1406251883Speter */ 1407251883Speter}; 1408251883Speter 1409251883Speter/* 1410251883Speter** CAPI3REF: Flags for the xAccess VFS method 1411251883Speter** 1412251883Speter** These integer constants can be used as the third parameter to 1413251883Speter** the xAccess method of an [sqlite3_vfs] object. They determine 1414251883Speter** what kind of permissions the xAccess method is looking for. 1415251883Speter** With SQLITE_ACCESS_EXISTS, the xAccess method 1416251883Speter** simply checks whether the file exists. 1417251883Speter** With SQLITE_ACCESS_READWRITE, the xAccess method 1418251883Speter** checks whether the named directory is both readable and writable 1419251883Speter** (in other words, if files can be added, removed, and renamed within 1420251883Speter** the directory). 1421251883Speter** The SQLITE_ACCESS_READWRITE constant is currently used only by the 1422251883Speter** [temp_store_directory pragma], though this could change in a future 1423251883Speter** release of SQLite. 1424251883Speter** With SQLITE_ACCESS_READ, the xAccess method 1425251883Speter** checks whether the file is readable. The SQLITE_ACCESS_READ constant is 1426251883Speter** currently unused, though it might be used in a future release of 1427251883Speter** SQLite. 1428251883Speter*/ 1429251883Speter#define SQLITE_ACCESS_EXISTS 0 1430251883Speter#define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */ 1431251883Speter#define SQLITE_ACCESS_READ 2 /* Unused */ 1432251883Speter 1433251883Speter/* 1434251883Speter** CAPI3REF: Flags for the xShmLock VFS method 1435251883Speter** 1436251883Speter** These integer constants define the various locking operations 1437251883Speter** allowed by the xShmLock method of [sqlite3_io_methods]. The 1438251883Speter** following are the only legal combinations of flags to the 1439251883Speter** xShmLock method: 1440251883Speter** 1441251883Speter** <ul> 1442251883Speter** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED 1443251883Speter** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE 1444251883Speter** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED 1445251883Speter** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE 1446251883Speter** </ul> 1447251883Speter** 1448251883Speter** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as 1449366076Scy** was given on the corresponding lock. 1450251883Speter** 1451251883Speter** The xShmLock method can transition between unlocked and SHARED or 1452251883Speter** between unlocked and EXCLUSIVE. It cannot transition between SHARED 1453251883Speter** and EXCLUSIVE. 1454251883Speter*/ 1455251883Speter#define SQLITE_SHM_UNLOCK 1 1456251883Speter#define SQLITE_SHM_LOCK 2 1457251883Speter#define SQLITE_SHM_SHARED 4 1458251883Speter#define SQLITE_SHM_EXCLUSIVE 8 1459251883Speter 1460251883Speter/* 1461251883Speter** CAPI3REF: Maximum xShmLock index 1462251883Speter** 1463251883Speter** The xShmLock method on [sqlite3_io_methods] may use values 1464251883Speter** between 0 and this upper bound as its "offset" argument. 1465251883Speter** The SQLite core will never attempt to acquire or release a 1466251883Speter** lock outside of this range 1467251883Speter*/ 1468251883Speter#define SQLITE_SHM_NLOCK 8 1469251883Speter 1470251883Speter 1471251883Speter/* 1472251883Speter** CAPI3REF: Initialize The SQLite Library 1473251883Speter** 1474251883Speter** ^The sqlite3_initialize() routine initializes the 1475251883Speter** SQLite library. ^The sqlite3_shutdown() routine 1476251883Speter** deallocates any resources that were allocated by sqlite3_initialize(). 1477251883Speter** These routines are designed to aid in process initialization and 1478251883Speter** shutdown on embedded systems. Workstation applications using 1479251883Speter** SQLite normally do not need to invoke either of these routines. 1480251883Speter** 1481251883Speter** A call to sqlite3_initialize() is an "effective" call if it is 1482251883Speter** the first time sqlite3_initialize() is invoked during the lifetime of 1483251883Speter** the process, or if it is the first time sqlite3_initialize() is invoked 1484251883Speter** following a call to sqlite3_shutdown(). ^(Only an effective call 1485251883Speter** of sqlite3_initialize() does any initialization. All other calls 1486251883Speter** are harmless no-ops.)^ 1487251883Speter** 1488251883Speter** A call to sqlite3_shutdown() is an "effective" call if it is the first 1489251883Speter** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only 1490251883Speter** an effective call to sqlite3_shutdown() does any deinitialization. 1491251883Speter** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^ 1492251883Speter** 1493251883Speter** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown() 1494251883Speter** is not. The sqlite3_shutdown() interface must only be called from a 1495251883Speter** single thread. All open [database connections] must be closed and all 1496251883Speter** other SQLite resources must be deallocated prior to invoking 1497251883Speter** sqlite3_shutdown(). 1498251883Speter** 1499251883Speter** Among other things, ^sqlite3_initialize() will invoke 1500251883Speter** sqlite3_os_init(). Similarly, ^sqlite3_shutdown() 1501251883Speter** will invoke sqlite3_os_end(). 1502251883Speter** 1503251883Speter** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success. 1504251883Speter** ^If for some reason, sqlite3_initialize() is unable to initialize 1505251883Speter** the library (perhaps it is unable to allocate a needed resource such 1506251883Speter** as a mutex) it returns an [error code] other than [SQLITE_OK]. 1507251883Speter** 1508251883Speter** ^The sqlite3_initialize() routine is called internally by many other 1509251883Speter** SQLite interfaces so that an application usually does not need to 1510251883Speter** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] 1511251883Speter** calls sqlite3_initialize() so the SQLite library will be automatically 1512251883Speter** initialized when [sqlite3_open()] is called if it has not be initialized 1513251883Speter** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] 1514251883Speter** compile-time option, then the automatic calls to sqlite3_initialize() 1515251883Speter** are omitted and the application must call sqlite3_initialize() directly 1516251883Speter** prior to using any other SQLite interface. For maximum portability, 1517251883Speter** it is recommended that applications always invoke sqlite3_initialize() 1518251883Speter** directly prior to using any other SQLite interface. Future releases 1519251883Speter** of SQLite may require this. In other words, the behavior exhibited 1520251883Speter** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the 1521251883Speter** default behavior in some future release of SQLite. 1522251883Speter** 1523251883Speter** The sqlite3_os_init() routine does operating-system specific 1524251883Speter** initialization of the SQLite library. The sqlite3_os_end() 1525251883Speter** routine undoes the effect of sqlite3_os_init(). Typical tasks 1526251883Speter** performed by these routines include allocation or deallocation 1527251883Speter** of static resources, initialization of global variables, 1528251883Speter** setting up a default [sqlite3_vfs] module, or setting up 1529251883Speter** a default configuration using [sqlite3_config()]. 1530251883Speter** 1531251883Speter** The application should never invoke either sqlite3_os_init() 1532251883Speter** or sqlite3_os_end() directly. The application should only invoke 1533251883Speter** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() 1534251883Speter** interface is called automatically by sqlite3_initialize() and 1535251883Speter** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate 1536251883Speter** implementations for sqlite3_os_init() and sqlite3_os_end() 1537251883Speter** are built into SQLite when it is compiled for Unix, Windows, or OS/2. 1538251883Speter** When [custom builds | built for other platforms] 1539251883Speter** (using the [SQLITE_OS_OTHER=1] compile-time 1540251883Speter** option) the application must supply a suitable implementation for 1541251883Speter** sqlite3_os_init() and sqlite3_os_end(). An application-supplied 1542251883Speter** implementation of sqlite3_os_init() or sqlite3_os_end() 1543251883Speter** must return [SQLITE_OK] on success and some other [error code] upon 1544251883Speter** failure. 1545251883Speter*/ 1546322444SpeterSQLITE_API int sqlite3_initialize(void); 1547322444SpeterSQLITE_API int sqlite3_shutdown(void); 1548322444SpeterSQLITE_API int sqlite3_os_init(void); 1549322444SpeterSQLITE_API int sqlite3_os_end(void); 1550251883Speter 1551251883Speter/* 1552251883Speter** CAPI3REF: Configuring The SQLite Library 1553251883Speter** 1554251883Speter** The sqlite3_config() interface is used to make global configuration 1555251883Speter** changes to SQLite in order to tune SQLite to the specific needs of 1556251883Speter** the application. The default configuration is recommended for most 1557251883Speter** applications and so this routine is usually not necessary. It is 1558251883Speter** provided to support rare applications with unusual needs. 1559251883Speter** 1560298161Sbapt** <b>The sqlite3_config() interface is not threadsafe. The application 1561298161Sbapt** must ensure that no other SQLite interfaces are invoked by other 1562298161Sbapt** threads while sqlite3_config() is running.</b> 1563298161Sbapt** 1564298161Sbapt** The sqlite3_config() interface 1565251883Speter** may only be invoked prior to library initialization using 1566251883Speter** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. 1567251883Speter** ^If sqlite3_config() is called after [sqlite3_initialize()] and before 1568251883Speter** [sqlite3_shutdown()] then it will return SQLITE_MISUSE. 1569251883Speter** Note, however, that ^sqlite3_config() can be called as part of the 1570251883Speter** implementation of an application-defined [sqlite3_os_init()]. 1571251883Speter** 1572251883Speter** The first argument to sqlite3_config() is an integer 1573251883Speter** [configuration option] that determines 1574251883Speter** what property of SQLite is to be configured. Subsequent arguments 1575251883Speter** vary depending on the [configuration option] 1576251883Speter** in the first argument. 1577251883Speter** 1578251883Speter** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. 1579251883Speter** ^If the option is unknown or SQLite is unable to set the option 1580251883Speter** then this routine returns a non-zero [error code]. 1581251883Speter*/ 1582322444SpeterSQLITE_API int sqlite3_config(int, ...); 1583251883Speter 1584251883Speter/* 1585251883Speter** CAPI3REF: Configure database connections 1586286510Speter** METHOD: sqlite3 1587251883Speter** 1588251883Speter** The sqlite3_db_config() interface is used to make configuration 1589251883Speter** changes to a [database connection]. The interface is similar to 1590251883Speter** [sqlite3_config()] except that the changes apply to a single 1591251883Speter** [database connection] (specified in the first argument). 1592251883Speter** 1593251883Speter** The second argument to sqlite3_db_config(D,V,...) is the 1594366076Scy** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code 1595251883Speter** that indicates what aspect of the [database connection] is being configured. 1596251883Speter** Subsequent arguments vary depending on the configuration verb. 1597251883Speter** 1598251883Speter** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if 1599251883Speter** the call is considered successful. 1600251883Speter*/ 1601322444SpeterSQLITE_API int sqlite3_db_config(sqlite3*, int op, ...); 1602251883Speter 1603251883Speter/* 1604251883Speter** CAPI3REF: Memory Allocation Routines 1605251883Speter** 1606251883Speter** An instance of this object defines the interface between SQLite 1607251883Speter** and low-level memory allocation routines. 1608251883Speter** 1609251883Speter** This object is used in only one place in the SQLite interface. 1610251883Speter** A pointer to an instance of this object is the argument to 1611251883Speter** [sqlite3_config()] when the configuration option is 1612366076Scy** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. 1613251883Speter** By creating an instance of this object 1614251883Speter** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC]) 1615251883Speter** during configuration, an application can specify an alternative 1616251883Speter** memory allocation subsystem for SQLite to use for all of its 1617251883Speter** dynamic memory needs. 1618251883Speter** 1619251883Speter** Note that SQLite comes with several [built-in memory allocators] 1620251883Speter** that are perfectly adequate for the overwhelming majority of applications 1621251883Speter** and that this object is only useful to a tiny minority of applications 1622251883Speter** with specialized memory allocation requirements. This object is 1623251883Speter** also used during testing of SQLite in order to specify an alternative 1624251883Speter** memory allocator that simulates memory out-of-memory conditions in 1625251883Speter** order to verify that SQLite recovers gracefully from such 1626251883Speter** conditions. 1627251883Speter** 1628251883Speter** The xMalloc, xRealloc, and xFree methods must work like the 1629251883Speter** malloc(), realloc() and free() functions from the standard C library. 1630251883Speter** ^SQLite guarantees that the second argument to 1631251883Speter** xRealloc is always a value returned by a prior call to xRoundup. 1632251883Speter** 1633251883Speter** xSize should return the allocated size of a memory allocation 1634251883Speter** previously obtained from xMalloc or xRealloc. The allocated size 1635251883Speter** is always at least as big as the requested size but may be larger. 1636251883Speter** 1637251883Speter** The xRoundup method returns what would be the allocated size of 1638251883Speter** a memory allocation given a particular requested size. Most memory 1639251883Speter** allocators round up memory allocations at least to the next multiple 1640251883Speter** of 8. Some allocators round up to a larger multiple or to a power of 2. 1641251883Speter** Every memory allocation request coming in through [sqlite3_malloc()] 1642366076Scy** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, 1643251883Speter** that causes the corresponding memory allocation to fail. 1644251883Speter** 1645269851Speter** The xInit method initializes the memory allocator. For example, 1646361456Scy** it might allocate any required mutexes or initialize internal data 1647251883Speter** structures. The xShutdown method is invoked (indirectly) by 1648251883Speter** [sqlite3_shutdown()] and should deallocate any resources acquired 1649251883Speter** by xInit. The pAppData pointer is used as the only parameter to 1650251883Speter** xInit and xShutdown. 1651251883Speter** 1652366076Scy** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes 1653251883Speter** the xInit method, so the xInit method need not be threadsafe. The 1654251883Speter** xShutdown method is only called from [sqlite3_shutdown()] so it does 1655251883Speter** not need to be threadsafe either. For all other methods, SQLite 1656251883Speter** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the 1657251883Speter** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which 1658251883Speter** it is by default) and so the methods are automatically serialized. 1659251883Speter** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other 1660251883Speter** methods must be threadsafe or else make their own arrangements for 1661251883Speter** serialization. 1662251883Speter** 1663251883Speter** SQLite will never invoke xInit() more than once without an intervening 1664251883Speter** call to xShutdown(). 1665251883Speter*/ 1666251883Spetertypedef struct sqlite3_mem_methods sqlite3_mem_methods; 1667251883Speterstruct sqlite3_mem_methods { 1668251883Speter void *(*xMalloc)(int); /* Memory allocation function */ 1669251883Speter void (*xFree)(void*); /* Free a prior allocation */ 1670251883Speter void *(*xRealloc)(void*,int); /* Resize an allocation */ 1671251883Speter int (*xSize)(void*); /* Return the size of an allocation */ 1672251883Speter int (*xRoundup)(int); /* Round up request size to allocation size */ 1673251883Speter int (*xInit)(void*); /* Initialize the memory allocator */ 1674251883Speter void (*xShutdown)(void*); /* Deinitialize the memory allocator */ 1675251883Speter void *pAppData; /* Argument to xInit() and xShutdown() */ 1676251883Speter}; 1677251883Speter 1678251883Speter/* 1679251883Speter** CAPI3REF: Configuration Options 1680251883Speter** KEYWORDS: {configuration option} 1681251883Speter** 1682251883Speter** These constants are the available integer configuration options that 1683251883Speter** can be passed as the first argument to the [sqlite3_config()] interface. 1684251883Speter** 1685251883Speter** New configuration options may be added in future releases of SQLite. 1686251883Speter** Existing configuration options might be discontinued. Applications 1687251883Speter** should check the return code from [sqlite3_config()] to make sure that 1688251883Speter** the call worked. The [sqlite3_config()] interface will return a 1689251883Speter** non-zero [error code] if a discontinued or unsupported configuration option 1690251883Speter** is invoked. 1691251883Speter** 1692251883Speter** <dl> 1693251883Speter** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt> 1694251883Speter** <dd>There are no arguments to this option. ^This option sets the 1695251883Speter** [threading mode] to Single-thread. In other words, it disables 1696251883Speter** all mutexing and puts SQLite into a mode where it can only be used 1697251883Speter** by a single thread. ^If SQLite is compiled with 1698251883Speter** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1699251883Speter** it is not possible to change the [threading mode] from its default 1700366076Scy** value of Single-thread and so [sqlite3_config()] will return 1701251883Speter** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD 1702251883Speter** configuration option.</dd> 1703251883Speter** 1704251883Speter** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt> 1705251883Speter** <dd>There are no arguments to this option. ^This option sets the 1706251883Speter** [threading mode] to Multi-thread. In other words, it disables 1707251883Speter** mutexing on [database connection] and [prepared statement] objects. 1708251883Speter** The application is responsible for serializing access to 1709251883Speter** [database connections] and [prepared statements]. But other mutexes 1710251883Speter** are enabled so that SQLite will be safe to use in a multi-threaded 1711251883Speter** environment as long as no two threads attempt to use the same 1712251883Speter** [database connection] at the same time. ^If SQLite is compiled with 1713251883Speter** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1714251883Speter** it is not possible to set the Multi-thread [threading mode] and 1715251883Speter** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1716251883Speter** SQLITE_CONFIG_MULTITHREAD configuration option.</dd> 1717251883Speter** 1718251883Speter** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt> 1719251883Speter** <dd>There are no arguments to this option. ^This option sets the 1720251883Speter** [threading mode] to Serialized. In other words, this option enables 1721251883Speter** all mutexes including the recursive 1722251883Speter** mutexes on [database connection] and [prepared statement] objects. 1723251883Speter** In this mode (which is the default when SQLite is compiled with 1724251883Speter** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access 1725251883Speter** to [database connections] and [prepared statements] so that the 1726251883Speter** application is free to use the same [database connection] or the 1727251883Speter** same [prepared statement] in different threads at the same time. 1728251883Speter** ^If SQLite is compiled with 1729251883Speter** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1730251883Speter** it is not possible to set the Serialized [threading mode] and 1731251883Speter** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1732251883Speter** SQLITE_CONFIG_SERIALIZED configuration option.</dd> 1733251883Speter** 1734251883Speter** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt> 1735366076Scy** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is 1736282328Sbapt** a pointer to an instance of the [sqlite3_mem_methods] structure. 1737282328Sbapt** The argument specifies 1738251883Speter** alternative low-level memory allocation routines to be used in place of 1739251883Speter** the memory allocation routines built into SQLite.)^ ^SQLite makes 1740251883Speter** its own private copy of the content of the [sqlite3_mem_methods] structure 1741251883Speter** before the [sqlite3_config()] call returns.</dd> 1742251883Speter** 1743251883Speter** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt> 1744282328Sbapt** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which 1745282328Sbapt** is a pointer to an instance of the [sqlite3_mem_methods] structure. 1746282328Sbapt** The [sqlite3_mem_methods] 1747251883Speter** structure is filled with the currently defined memory allocation routines.)^ 1748251883Speter** This option can be used to overload the default memory allocation 1749251883Speter** routines with a wrapper that simulations memory allocation failure or 1750251883Speter** tracks memory usage, for example. </dd> 1751251883Speter** 1752342292Scy** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt> 1753342292Scy** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of 1754342292Scy** type int, interpreted as a boolean, which if true provides a hint to 1755342292Scy** SQLite that it should avoid large memory allocations if possible. 1756342292Scy** SQLite will run faster if it is free to make large memory allocations, 1757342292Scy** but some application might prefer to run slower in exchange for 1758342292Scy** guarantees about memory fragmentation that are possible if large 1759342292Scy** allocations are avoided. This hint is normally off. 1760342292Scy** </dd> 1761342292Scy** 1762251883Speter** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt> 1763282328Sbapt** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int, 1764282328Sbapt** interpreted as a boolean, which enables or disables the collection of 1765282328Sbapt** memory allocation statistics. ^(When memory allocation statistics are 1766282328Sbapt** disabled, the following SQLite interfaces become non-operational: 1767251883Speter** <ul> 1768361456Scy** <li> [sqlite3_hard_heap_limit64()] 1769251883Speter** <li> [sqlite3_memory_used()] 1770251883Speter** <li> [sqlite3_memory_highwater()] 1771251883Speter** <li> [sqlite3_soft_heap_limit64()] 1772282328Sbapt** <li> [sqlite3_status64()] 1773251883Speter** </ul>)^ 1774251883Speter** ^Memory allocation statistics are enabled by default unless SQLite is 1775251883Speter** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory 1776251883Speter** allocation statistics are disabled by default. 1777251883Speter** </dd> 1778251883Speter** 1779251883Speter** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt> 1780342292Scy** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used. 1781282328Sbapt** </dd> 1782251883Speter** 1783251883Speter** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt> 1784298161Sbapt** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool 1785282328Sbapt** that SQLite can use for the database page cache with the default page 1786366076Scy** cache implementation. 1787361456Scy** This configuration option is a no-op if an application-defined page 1788298161Sbapt** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2]. 1789282328Sbapt** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to 1790298161Sbapt** 8-byte aligned memory (pMem), the size of each page cache line (sz), 1791298161Sbapt** and the number of cache lines (N). 1792251883Speter** The sz argument should be the size of the largest database page 1793282328Sbapt** (a power of two between 512 and 65536) plus some extra bytes for each 1794282328Sbapt** page header. ^The number of extra bytes needed by the page header 1795298161Sbapt** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ]. 1796282328Sbapt** ^It is harmless, apart from the wasted memory, 1797298161Sbapt** for the sz parameter to be larger than necessary. The pMem 1798298161Sbapt** argument must be either a NULL pointer or a pointer to an 8-byte 1799298161Sbapt** aligned block of memory of at least sz*N bytes, otherwise 1800298161Sbapt** subsequent behavior is undefined. 1801298161Sbapt** ^When pMem is not NULL, SQLite will strive to use the memory provided 1802298161Sbapt** to satisfy page cache needs, falling back to [sqlite3_malloc()] if 1803298161Sbapt** a page cache line is larger than sz bytes or if all of the pMem buffer 1804298161Sbapt** is exhausted. 1805298161Sbapt** ^If pMem is NULL and N is non-zero, then each database connection 1806298161Sbapt** does an initial bulk allocation for page cache memory 1807298161Sbapt** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or 1808298161Sbapt** of -1024*N bytes if N is negative, . ^If additional 1809298161Sbapt** page cache memory is needed beyond what is provided by the initial 1810298161Sbapt** allocation, then SQLite goes to [sqlite3_malloc()] separately for each 1811298161Sbapt** additional cache line. </dd> 1812251883Speter** 1813251883Speter** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt> 1814366076Scy** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer 1815282328Sbapt** that SQLite will use for all of its dynamic memory allocation needs 1816342292Scy** beyond those provided for by [SQLITE_CONFIG_PAGECACHE]. 1817282328Sbapt** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled 1818282328Sbapt** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns 1819282328Sbapt** [SQLITE_ERROR] if invoked otherwise. 1820282328Sbapt** ^There are three arguments to SQLITE_CONFIG_HEAP: 1821282328Sbapt** An 8-byte aligned pointer to the memory, 1822251883Speter** the number of bytes in the memory buffer, and the minimum allocation size. 1823251883Speter** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts 1824251883Speter** to using its default memory allocator (the system malloc() implementation), 1825251883Speter** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the 1826282328Sbapt** memory pointer is not NULL then the alternative memory 1827251883Speter** allocator is engaged to handle all of SQLites memory allocation needs. 1828251883Speter** The first pointer (the memory pointer) must be aligned to an 8-byte 1829251883Speter** boundary or subsequent behavior of SQLite will be undefined. 1830251883Speter** The minimum allocation size is capped at 2**12. Reasonable values 1831251883Speter** for the minimum allocation size are 2**5 through 2**8.</dd> 1832251883Speter** 1833251883Speter** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt> 1834282328Sbapt** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a 1835282328Sbapt** pointer to an instance of the [sqlite3_mutex_methods] structure. 1836282328Sbapt** The argument specifies alternative low-level mutex routines to be used 1837282328Sbapt** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of 1838282328Sbapt** the content of the [sqlite3_mutex_methods] structure before the call to 1839251883Speter** [sqlite3_config()] returns. ^If SQLite is compiled with 1840251883Speter** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1841251883Speter** the entire mutexing subsystem is omitted from the build and hence calls to 1842251883Speter** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will 1843251883Speter** return [SQLITE_ERROR].</dd> 1844251883Speter** 1845251883Speter** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt> 1846282328Sbapt** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which 1847282328Sbapt** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The 1848251883Speter** [sqlite3_mutex_methods] 1849251883Speter** structure is filled with the currently defined mutex routines.)^ 1850251883Speter** This option can be used to overload the default mutex allocation 1851251883Speter** routines with a wrapper used to track mutex usage for performance 1852251883Speter** profiling or testing, for example. ^If SQLite is compiled with 1853251883Speter** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1854251883Speter** the entire mutexing subsystem is omitted from the build and hence calls to 1855251883Speter** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will 1856251883Speter** return [SQLITE_ERROR].</dd> 1857251883Speter** 1858251883Speter** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt> 1859282328Sbapt** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine 1860282328Sbapt** the default size of lookaside memory on each [database connection]. 1861282328Sbapt** The first argument is the 1862251883Speter** size of each lookaside buffer slot and the second is the number of 1863282328Sbapt** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE 1864282328Sbapt** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE] 1865282328Sbapt** option to [sqlite3_db_config()] can be used to change the lookaside 1866251883Speter** configuration on individual connections.)^ </dd> 1867251883Speter** 1868251883Speter** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt> 1869366076Scy** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is 1870282328Sbapt** a pointer to an [sqlite3_pcache_methods2] object. This object specifies 1871282328Sbapt** the interface to a custom page cache implementation.)^ 1872282328Sbapt** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd> 1873251883Speter** 1874251883Speter** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt> 1875282328Sbapt** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which 1876282328Sbapt** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of 1877282328Sbapt** the current page cache implementation into that object.)^ </dd> 1878251883Speter** 1879251883Speter** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt> 1880251883Speter** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite 1881251883Speter** global [error log]. 1882251883Speter** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a 1883366076Scy** function with a call signature of void(*)(void*,int,const char*), 1884251883Speter** and a pointer to void. ^If the function pointer is not NULL, it is 1885251883Speter** invoked by [sqlite3_log()] to process each logging event. ^If the 1886251883Speter** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op. 1887251883Speter** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is 1888251883Speter** passed through as the first parameter to the application-defined logger 1889251883Speter** function whenever that function is invoked. ^The second parameter to 1890251883Speter** the logger function is a copy of the first parameter to the corresponding 1891251883Speter** [sqlite3_log()] call and is intended to be a [result code] or an 1892251883Speter** [extended result code]. ^The third parameter passed to the logger is 1893251883Speter** log message after formatting via [sqlite3_snprintf()]. 1894251883Speter** The SQLite logging interface is not reentrant; the logger function 1895251883Speter** supplied by the application must not invoke any SQLite interface. 1896251883Speter** In a multi-threaded application, the application-defined logger 1897251883Speter** function must be threadsafe. </dd> 1898251883Speter** 1899251883Speter** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI 1900282328Sbapt** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int. 1901282328Sbapt** If non-zero, then URI handling is globally enabled. If the parameter is zero, 1902282328Sbapt** then URI handling is globally disabled.)^ ^If URI handling is globally 1903282328Sbapt** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()], 1904282328Sbapt** [sqlite3_open16()] or 1905251883Speter** specified as part of [ATTACH] commands are interpreted as URIs, regardless 1906251883Speter** of whether or not the [SQLITE_OPEN_URI] flag is set when the database 1907269851Speter** connection is opened. ^If it is globally disabled, filenames are 1908251883Speter** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the 1909269851Speter** database connection is opened. ^(By default, URI handling is globally 1910251883Speter** disabled. The default value may be changed by compiling with the 1911269851Speter** [SQLITE_USE_URI] symbol defined.)^ 1912251883Speter** 1913251883Speter** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN 1914282328Sbapt** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer 1915282328Sbapt** argument which is interpreted as a boolean in order to enable or disable 1916282328Sbapt** the use of covering indices for full table scans in the query optimizer. 1917282328Sbapt** ^The default setting is determined 1918251883Speter** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on" 1919251883Speter** if that compile-time option is omitted. 1920251883Speter** The ability to disable the use of covering indices for full table scans 1921251883Speter** is because some incorrectly coded legacy applications might malfunction 1922269851Speter** when the optimization is enabled. Providing the ability to 1923251883Speter** disable the optimization allows the older, buggy application code to work 1924251883Speter** without change even with newer versions of SQLite. 1925251883Speter** 1926251883Speter** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]] 1927251883Speter** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE 1928251883Speter** <dd> These options are obsolete and should not be used by new code. 1929251883Speter** They are retained for backwards compatibility but are now no-ops. 1930251883Speter** </dd> 1931251883Speter** 1932251883Speter** [[SQLITE_CONFIG_SQLLOG]] 1933251883Speter** <dt>SQLITE_CONFIG_SQLLOG 1934251883Speter** <dd>This option is only available if sqlite is compiled with the 1935251883Speter** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should 1936251883Speter** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int). 1937251883Speter** The second should be of type (void*). The callback is invoked by the library 1938251883Speter** in three separate circumstances, identified by the value passed as the 1939251883Speter** fourth parameter. If the fourth parameter is 0, then the database connection 1940251883Speter** passed as the second argument has just been opened. The third argument 1941251883Speter** points to a buffer containing the name of the main database file. If the 1942251883Speter** fourth parameter is 1, then the SQL statement that the third parameter 1943251883Speter** points to has just been executed. Or, if the fourth parameter is 2, then 1944251883Speter** the connection being passed as the second parameter is being closed. The 1945251883Speter** third parameter is passed NULL In this case. An example of using this 1946251883Speter** configuration option can be seen in the "test_sqllog.c" source file in 1947251883Speter** the canonical SQLite source tree.</dd> 1948251883Speter** 1949251883Speter** [[SQLITE_CONFIG_MMAP_SIZE]] 1950251883Speter** <dt>SQLITE_CONFIG_MMAP_SIZE 1951269851Speter** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values 1952251883Speter** that are the default mmap size limit (the default setting for 1953251883Speter** [PRAGMA mmap_size]) and the maximum allowed mmap size limit. 1954269851Speter** ^The default setting can be overridden by each database connection using 1955251883Speter** either the [PRAGMA mmap_size] command, or by using the 1956269851Speter** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size 1957282328Sbapt** will be silently truncated if necessary so that it does not exceed the 1958282328Sbapt** compile-time maximum mmap size set by the 1959269851Speter** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^ 1960269851Speter** ^If either argument to this option is negative, then that argument is 1961251883Speter** changed to its compile-time default. 1962269851Speter** 1963269851Speter** [[SQLITE_CONFIG_WIN32_HEAPSIZE]] 1964269851Speter** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE 1965282328Sbapt** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is 1966282328Sbapt** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro 1967282328Sbapt** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value 1968269851Speter** that specifies the maximum size of the created heap. 1969282328Sbapt** 1970282328Sbapt** [[SQLITE_CONFIG_PCACHE_HDRSZ]] 1971282328Sbapt** <dt>SQLITE_CONFIG_PCACHE_HDRSZ 1972282328Sbapt** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which 1973282328Sbapt** is a pointer to an integer and writes into that integer the number of extra 1974282328Sbapt** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE]. 1975282328Sbapt** The amount of extra space required can change depending on the compiler, 1976282328Sbapt** target platform, and SQLite version. 1977282328Sbapt** 1978282328Sbapt** [[SQLITE_CONFIG_PMASZ]] 1979282328Sbapt** <dt>SQLITE_CONFIG_PMASZ 1980282328Sbapt** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which 1981282328Sbapt** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded 1982282328Sbapt** sorter to that integer. The default minimum PMA Size is set by the 1983282328Sbapt** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched 1984282328Sbapt** to help with sort operations when multithreaded sorting 1985282328Sbapt** is enabled (using the [PRAGMA threads] command) and the amount of content 1986282328Sbapt** to be sorted exceeds the page size times the minimum of the 1987282328Sbapt** [PRAGMA cache_size] setting and this value. 1988298161Sbapt** 1989298161Sbapt** [[SQLITE_CONFIG_STMTJRNL_SPILL]] 1990298161Sbapt** <dt>SQLITE_CONFIG_STMTJRNL_SPILL 1991298161Sbapt** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which 1992366076Scy** becomes the [statement journal] spill-to-disk threshold. 1993298161Sbapt** [Statement journals] are held in memory until their size (in bytes) 1994298161Sbapt** exceeds this threshold, at which point they are written to disk. 1995298161Sbapt** Or if the threshold is -1, statement journals are always held 1996298161Sbapt** exclusively in memory. 1997298161Sbapt** Since many statement journals never become large, setting the spill 1998298161Sbapt** threshold to a value such as 64KiB can greatly reduce the amount of 1999298161Sbapt** I/O required to support statement rollback. 2000298161Sbapt** The default value for this setting is controlled by the 2001298161Sbapt** [SQLITE_STMTJRNL_SPILL] compile-time option. 2002342292Scy** 2003342292Scy** [[SQLITE_CONFIG_SORTERREF_SIZE]] 2004342292Scy** <dt>SQLITE_CONFIG_SORTERREF_SIZE 2005342292Scy** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter 2006342292Scy** of type (int) - the new value of the sorter-reference size threshold. 2007342292Scy** Usually, when SQLite uses an external sort to order records according 2008342292Scy** to an ORDER BY clause, all fields required by the caller are present in the 2009342292Scy** sorted records. However, if SQLite determines based on the declared type 2010342292Scy** of a table column that its values are likely to be very large - larger 2011342292Scy** than the configured sorter-reference size threshold - then a reference 2012342292Scy** is stored in each sorted record and the required column values loaded 2013342292Scy** from the database as records are returned in sorted order. The default 2014366076Scy** value for this option is to never use this optimization. Specifying a 2015342292Scy** negative value for this option restores the default behaviour. 2016342292Scy** This option is only available if SQLite is compiled with the 2017342292Scy** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option. 2018346442Scy** 2019346442Scy** [[SQLITE_CONFIG_MEMDB_MAXSIZE]] 2020346442Scy** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE 2021346442Scy** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter 2022346442Scy** [sqlite3_int64] parameter which is the default maximum size for an in-memory 2023346442Scy** database created using [sqlite3_deserialize()]. This default maximum 2024346442Scy** size can be adjusted up or down for individual databases using the 2025346442Scy** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control]. If this 2026346442Scy** configuration setting is never used, then the default maximum is determined 2027346442Scy** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option. If that 2028346442Scy** compile-time option is not set, then the default maximum is 1073741824. 2029251883Speter** </dl> 2030251883Speter*/ 2031251883Speter#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ 2032251883Speter#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ 2033251883Speter#define SQLITE_CONFIG_SERIALIZED 3 /* nil */ 2034251883Speter#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ 2035251883Speter#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ 2036342292Scy#define SQLITE_CONFIG_SCRATCH 6 /* No longer used */ 2037251883Speter#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ 2038251883Speter#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ 2039251883Speter#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ 2040251883Speter#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ 2041251883Speter#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ 2042366076Scy/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ 2043251883Speter#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ 2044251883Speter#define SQLITE_CONFIG_PCACHE 14 /* no-op */ 2045251883Speter#define SQLITE_CONFIG_GETPCACHE 15 /* no-op */ 2046251883Speter#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */ 2047251883Speter#define SQLITE_CONFIG_URI 17 /* int */ 2048251883Speter#define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */ 2049251883Speter#define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */ 2050251883Speter#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */ 2051251883Speter#define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */ 2052251883Speter#define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */ 2053269851Speter#define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */ 2054282328Sbapt#define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */ 2055282328Sbapt#define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */ 2056298161Sbapt#define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */ 2057342292Scy#define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */ 2058342292Scy#define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */ 2059346442Scy#define SQLITE_CONFIG_MEMDB_MAXSIZE 29 /* sqlite3_int64 */ 2060251883Speter 2061251883Speter/* 2062251883Speter** CAPI3REF: Database Connection Configuration Options 2063251883Speter** 2064251883Speter** These constants are the available integer configuration options that 2065251883Speter** can be passed as the second argument to the [sqlite3_db_config()] interface. 2066251883Speter** 2067251883Speter** New configuration options may be added in future releases of SQLite. 2068251883Speter** Existing configuration options might be discontinued. Applications 2069251883Speter** should check the return code from [sqlite3_db_config()] to make sure that 2070251883Speter** the call worked. ^The [sqlite3_db_config()] interface will return a 2071251883Speter** non-zero [error code] if a discontinued or unsupported configuration option 2072251883Speter** is invoked. 2073251883Speter** 2074251883Speter** <dl> 2075342292Scy** [[SQLITE_DBCONFIG_LOOKASIDE]] 2076251883Speter** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt> 2077366076Scy** <dd> ^This option takes three additional arguments that determine the 2078251883Speter** [lookaside memory allocator] configuration for the [database connection]. 2079251883Speter** ^The first argument (the third parameter to [sqlite3_db_config()] is a 2080251883Speter** pointer to a memory buffer to use for lookaside memory. 2081251883Speter** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb 2082251883Speter** may be NULL in which case SQLite will allocate the 2083251883Speter** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the 2084251883Speter** size of each lookaside buffer slot. ^The third argument is the number of 2085251883Speter** slots. The size of the buffer in the first argument must be greater than 2086251883Speter** or equal to the product of the second and third arguments. The buffer 2087251883Speter** must be aligned to an 8-byte boundary. ^If the second argument to 2088251883Speter** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally 2089251883Speter** rounded down to the next smaller multiple of 8. ^(The lookaside memory 2090251883Speter** configuration for a database connection can only be changed when that 2091251883Speter** connection is not currently using lookaside memory, or in other words 2092251883Speter** when the "current value" returned by 2093251883Speter** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero. 2094251883Speter** Any attempt to change the lookaside memory configuration when lookaside 2095366076Scy** memory is in use leaves the configuration unchanged and returns 2096251883Speter** [SQLITE_BUSY].)^</dd> 2097251883Speter** 2098342292Scy** [[SQLITE_DBCONFIG_ENABLE_FKEY]] 2099251883Speter** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt> 2100251883Speter** <dd> ^This option is used to enable or disable the enforcement of 2101251883Speter** [foreign key constraints]. There should be two additional arguments. 2102251883Speter** The first argument is an integer which is 0 to disable FK enforcement, 2103251883Speter** positive to enable FK enforcement or negative to leave FK enforcement 2104251883Speter** unchanged. The second parameter is a pointer to an integer into which 2105251883Speter** is written 0 or 1 to indicate whether FK enforcement is off or on 2106251883Speter** following this call. The second parameter may be a NULL pointer, in 2107251883Speter** which case the FK enforcement setting is not reported back. </dd> 2108251883Speter** 2109342292Scy** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]] 2110251883Speter** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt> 2111251883Speter** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers]. 2112251883Speter** There should be two additional arguments. 2113251883Speter** The first argument is an integer which is 0 to disable triggers, 2114251883Speter** positive to enable triggers or negative to leave the setting unchanged. 2115251883Speter** The second parameter is a pointer to an integer into which 2116251883Speter** is written 0 or 1 to indicate whether triggers are disabled or enabled 2117251883Speter** following this call. The second parameter may be a NULL pointer, in 2118369951Scy** which case the trigger setting is not reported back. 2119251883Speter** 2120369951Scy** <p>Originally this option disabled all triggers. ^(However, since 2121369951Scy** SQLite version 3.35.0, TEMP triggers are still allowed even if 2122369951Scy** this option is off. So, in other words, this option now only disables 2123369951Scy** triggers in the main database schema or in the schemas of ATTACH-ed 2124369951Scy** databases.)^ </dd> 2125369951Scy** 2126355326Scy** [[SQLITE_DBCONFIG_ENABLE_VIEW]] 2127355326Scy** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt> 2128355326Scy** <dd> ^This option is used to enable or disable [CREATE VIEW | views]. 2129355326Scy** There should be two additional arguments. 2130355326Scy** The first argument is an integer which is 0 to disable views, 2131355326Scy** positive to enable views or negative to leave the setting unchanged. 2132355326Scy** The second parameter is a pointer to an integer into which 2133355326Scy** is written 0 or 1 to indicate whether views are disabled or enabled 2134355326Scy** following this call. The second parameter may be a NULL pointer, in 2135369951Scy** which case the view setting is not reported back. 2136355326Scy** 2137369951Scy** <p>Originally this option disabled all views. ^(However, since 2138369951Scy** SQLite version 3.35.0, TEMP views are still allowed even if 2139369951Scy** this option is off. So, in other words, this option now only disables 2140369951Scy** views in the main database schema or in the schemas of ATTACH-ed 2141369951Scy** databases.)^ </dd> 2142369951Scy** 2143342292Scy** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]] 2144298161Sbapt** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt> 2145347347Scy** <dd> ^This option is used to enable or disable the 2146347347Scy** [fts3_tokenizer()] function which is part of the 2147298161Sbapt** [FTS3] full-text search engine extension. 2148298161Sbapt** There should be two additional arguments. 2149298161Sbapt** The first argument is an integer which is 0 to disable fts3_tokenizer() or 2150298161Sbapt** positive to enable fts3_tokenizer() or negative to leave the setting 2151298161Sbapt** unchanged. 2152298161Sbapt** The second parameter is a pointer to an integer into which 2153298161Sbapt** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled 2154298161Sbapt** following this call. The second parameter may be a NULL pointer, in 2155298161Sbapt** which case the new setting is not reported back. </dd> 2156298161Sbapt** 2157342292Scy** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]] 2158305002Scy** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt> 2159305002Scy** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()] 2160305002Scy** interface independently of the [load_extension()] SQL function. 2161305002Scy** The [sqlite3_enable_load_extension()] API enables or disables both the 2162305002Scy** C-API [sqlite3_load_extension()] and the SQL function [load_extension()]. 2163305002Scy** There should be two additional arguments. 2164305002Scy** When the first argument to this interface is 1, then only the C-API is 2165305002Scy** enabled and the SQL function remains disabled. If the first argument to 2166305002Scy** this interface is 0, then both the C-API and the SQL function are disabled. 2167305002Scy** If the first argument is -1, then no changes are made to state of either the 2168305002Scy** C-API or the SQL function. 2169305002Scy** The second parameter is a pointer to an integer into which 2170305002Scy** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface 2171305002Scy** is disabled or enabled following this call. The second parameter may 2172305002Scy** be a NULL pointer, in which case the new setting is not reported back. 2173305002Scy** </dd> 2174305002Scy** 2175342292Scy** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt> 2176322444Speter** <dd> ^This option is used to change the name of the "main" database 2177322444Speter** schema. ^The sole argument is a pointer to a constant UTF8 string 2178322444Speter** which will become the new schema name in place of "main". ^SQLite 2179322444Speter** does not make a copy of the new main schema name string, so the application 2180322444Speter** must ensure that the argument passed into this DBCONFIG option is unchanged 2181322444Speter** until after the database connection closes. 2182322444Speter** </dd> 2183322444Speter** 2184366076Scy** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]] 2185322444Speter** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt> 2186366076Scy** <dd> Usually, when a database in wal mode is closed or detached from a 2187366076Scy** database handle, SQLite checks if this will mean that there are now no 2188366076Scy** connections at all to the database. If so, it performs a checkpoint 2189322444Speter** operation before closing the connection. This option may be used to 2190322444Speter** override this behaviour. The first parameter passed to this operation 2191342292Scy** is an integer - positive to disable checkpoints-on-close, or zero (the 2192342292Scy** default) to enable them, and negative to leave the setting unchanged. 2193342292Scy** The second parameter is a pointer to an integer 2194322444Speter** into which is written 0 or 1 to indicate whether checkpoints-on-close 2195322444Speter** have been disabled - 0 if they are not disabled, 1 if they are. 2196322444Speter** </dd> 2197322444Speter** 2198342292Scy** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt> 2199322444Speter** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates 2200322444Speter** the [query planner stability guarantee] (QPSG). When the QPSG is active, 2201322444Speter** a single SQL query statement will always use the same algorithm regardless 2202322444Speter** of values of [bound parameters].)^ The QPSG disables some query optimizations 2203322444Speter** that look at the values of bound parameters, which can make some queries 2204322444Speter** slower. But the QPSG has the advantage of more predictable behavior. With 2205322444Speter** the QPSG active, SQLite will always use the same query plan in the field as 2206322444Speter** was used during testing in the lab. 2207366076Scy** The first argument to this setting is an integer which is 0 to disable 2208342292Scy** the QPSG, positive to enable QPSG, or negative to leave the setting 2209342292Scy** unchanged. The second parameter is a pointer to an integer into which 2210342292Scy** is written 0 or 1 to indicate whether the QPSG is disabled or enabled 2211342292Scy** following this call. 2212322444Speter** </dd> 2213322444Speter** 2214342292Scy** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt> 2215366076Scy** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not 2216342292Scy** include output for any operations performed by trigger programs. This 2217342292Scy** option is used to set or clear (the default) a flag that governs this 2218342292Scy** behavior. The first parameter passed to this operation is an integer - 2219342292Scy** positive to enable output for trigger programs, or zero to disable it, 2220342292Scy** or negative to leave the setting unchanged. 2221366076Scy** The second parameter is a pointer to an integer into which is written 2222366076Scy** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if 2223366076Scy** it is not disabled, 1 if it is. 2224342292Scy** </dd> 2225342292Scy** 2226342292Scy** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt> 2227342292Scy** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run 2228342292Scy** [VACUUM] in order to reset a database back to an empty database 2229342292Scy** with no schema and no content. The following process works even for 2230342292Scy** a badly corrupted database file: 2231342292Scy** <ol> 2232342292Scy** <li> If the database connection is newly opened, make sure it has read the 2233342292Scy** database schema by preparing then discarding some query against the 2234342292Scy** database, or calling sqlite3_table_column_metadata(), ignoring any 2235342292Scy** errors. This step is only necessary if the application desires to keep 2236342292Scy** the database in WAL mode after the reset if it was in WAL mode before 2237366076Scy** the reset. 2238342292Scy** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0); 2239342292Scy** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0); 2240342292Scy** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0); 2241342292Scy** </ol> 2242342292Scy** Because resetting a database is destructive and irreversible, the 2243342292Scy** process requires the use of this obscure API and multiple steps to help 2244342292Scy** ensure that it does not happen by accident. 2245342292Scy** 2246342292Scy** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt> 2247342292Scy** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the 2248342292Scy** "defensive" flag for a database connection. When the defensive 2249366076Scy** flag is enabled, language features that allow ordinary SQL to 2250342292Scy** deliberately corrupt the database file are disabled. The disabled 2251342292Scy** features include but are not limited to the following: 2252342292Scy** <ul> 2253342292Scy** <li> The [PRAGMA writable_schema=ON] statement. 2254351633Scy** <li> The [PRAGMA journal_mode=OFF] statement. 2255342292Scy** <li> Writes to the [sqlite_dbpage] virtual table. 2256342292Scy** <li> Direct writes to [shadow tables]. 2257342292Scy** </ul> 2258342292Scy** </dd> 2259347347Scy** 2260347347Scy** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt> 2261347347Scy** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the 2262347347Scy** "writable_schema" flag. This has the same effect and is logically equivalent 2263347347Scy** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF]. 2264366076Scy** The first argument to this setting is an integer which is 0 to disable 2265347347Scy** the writable_schema, positive to enable writable_schema, or negative to 2266347347Scy** leave the setting unchanged. The second parameter is a pointer to an 2267347347Scy** integer into which is written 0 or 1 to indicate whether the writable_schema 2268347347Scy** is enabled or disabled following this call. 2269347347Scy** </dd> 2270351633Scy** 2271351633Scy** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]] 2272351633Scy** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt> 2273351633Scy** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates 2274351633Scy** the legacy behavior of the [ALTER TABLE RENAME] command such it 2275351633Scy** behaves as it did prior to [version 3.24.0] (2018-06-04). See the 2276351633Scy** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for 2277351633Scy** additional information. This feature can also be turned on and off 2278351633Scy** using the [PRAGMA legacy_alter_table] statement. 2279351633Scy** </dd> 2280351633Scy** 2281351633Scy** [[SQLITE_DBCONFIG_DQS_DML]] 2282351633Scy** <dt>SQLITE_DBCONFIG_DQS_DML</td> 2283351633Scy** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates 2284361456Scy** the legacy [double-quoted string literal] misfeature for DML statements 2285351633Scy** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The 2286351633Scy** default value of this setting is determined by the [-DSQLITE_DQS] 2287351633Scy** compile-time option. 2288351633Scy** </dd> 2289351633Scy** 2290351633Scy** [[SQLITE_DBCONFIG_DQS_DDL]] 2291351633Scy** <dt>SQLITE_DBCONFIG_DQS_DDL</td> 2292351633Scy** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates 2293351633Scy** the legacy [double-quoted string literal] misfeature for DDL statements, 2294351633Scy** such as CREATE TABLE and CREATE INDEX. The 2295351633Scy** default value of this setting is determined by the [-DSQLITE_DQS] 2296351633Scy** compile-time option. 2297351633Scy** </dd> 2298361456Scy** 2299361456Scy** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]] 2300361456Scy** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</td> 2301361456Scy** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to 2302366076Scy** assume that database schemas are untainted by malicious content. 2303361456Scy** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite 2304361456Scy** takes additional defensive steps to protect the application from harm 2305361456Scy** including: 2306361456Scy** <ul> 2307361456Scy** <li> Prohibit the use of SQL functions inside triggers, views, 2308366076Scy** CHECK constraints, DEFAULT clauses, expression indexes, 2309361456Scy** partial indexes, or generated columns 2310361456Scy** unless those functions are tagged with [SQLITE_INNOCUOUS]. 2311361456Scy** <li> Prohibit the use of virtual tables inside of triggers or views 2312361456Scy** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS]. 2313361456Scy** </ul> 2314361456Scy** This setting defaults to "on" for legacy compatibility, however 2315361456Scy** all applications are advised to turn it off if possible. This setting 2316361456Scy** can also be controlled using the [PRAGMA trusted_schema] statement. 2317361456Scy** </dd> 2318361456Scy** 2319361456Scy** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]] 2320361456Scy** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</td> 2321361456Scy** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates 2322361456Scy** the legacy file format flag. When activated, this flag causes all newly 2323361456Scy** created database file to have a schema format version number (the 4-byte 2324361456Scy** integer found at offset 44 into the database header) of 1. This in turn 2325361456Scy** means that the resulting database file will be readable and writable by 2326361456Scy** any SQLite version back to 3.0.0 ([dateof:3.0.0]). Without this setting, 2327361456Scy** newly created databases are generally not understandable by SQLite versions 2328361456Scy** prior to 3.3.0 ([dateof:3.3.0]). As these words are written, there 2329366076Scy** is now scarcely any need to generated database files that are compatible 2330361456Scy** all the way back to version 3.0.0, and so this setting is of little 2331361456Scy** practical use, but is provided so that SQLite can continue to claim the 2332361456Scy** ability to generate new database files that are compatible with version 2333361456Scy** 3.0.0. 2334361456Scy** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on, 2335361456Scy** the [VACUUM] command will fail with an obscure error when attempting to 2336361456Scy** process a table with generated columns and a descending index. This is 2337361456Scy** not considered a bug since SQLite versions 3.3.0 and earlier do not support 2338361456Scy** either generated columns or decending indexes. 2339361456Scy** </dd> 2340251883Speter** </dl> 2341251883Speter*/ 2342322444Speter#define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */ 2343298161Sbapt#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ 2344298161Sbapt#define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */ 2345298161Sbapt#define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */ 2346298161Sbapt#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */ 2347305002Scy#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */ 2348322444Speter#define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */ 2349322444Speter#define SQLITE_DBCONFIG_ENABLE_QPSG 1007 /* int int* */ 2350342292Scy#define SQLITE_DBCONFIG_TRIGGER_EQP 1008 /* int int* */ 2351342292Scy#define SQLITE_DBCONFIG_RESET_DATABASE 1009 /* int int* */ 2352342292Scy#define SQLITE_DBCONFIG_DEFENSIVE 1010 /* int int* */ 2353347347Scy#define SQLITE_DBCONFIG_WRITABLE_SCHEMA 1011 /* int int* */ 2354351633Scy#define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE 1012 /* int int* */ 2355351633Scy#define SQLITE_DBCONFIG_DQS_DML 1013 /* int int* */ 2356351633Scy#define SQLITE_DBCONFIG_DQS_DDL 1014 /* int int* */ 2357355326Scy#define SQLITE_DBCONFIG_ENABLE_VIEW 1015 /* int int* */ 2358361456Scy#define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT 1016 /* int int* */ 2359361456Scy#define SQLITE_DBCONFIG_TRUSTED_SCHEMA 1017 /* int int* */ 2360361456Scy#define SQLITE_DBCONFIG_MAX 1017 /* Largest DBCONFIG */ 2361251883Speter 2362251883Speter/* 2363251883Speter** CAPI3REF: Enable Or Disable Extended Result Codes 2364286510Speter** METHOD: sqlite3 2365251883Speter** 2366251883Speter** ^The sqlite3_extended_result_codes() routine enables or disables the 2367251883Speter** [extended result codes] feature of SQLite. ^The extended result 2368251883Speter** codes are disabled by default for historical compatibility. 2369251883Speter*/ 2370322444SpeterSQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff); 2371251883Speter 2372251883Speter/* 2373251883Speter** CAPI3REF: Last Insert Rowid 2374286510Speter** METHOD: sqlite3 2375251883Speter** 2376269851Speter** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables) 2377269851Speter** has a unique 64-bit signed 2378251883Speter** integer key called the [ROWID | "rowid"]. ^The rowid is always available 2379251883Speter** as an undeclared column named ROWID, OID, or _ROWID_ as long as those 2380251883Speter** names are not also used by explicitly declared columns. ^If 2381251883Speter** the table has a column of type [INTEGER PRIMARY KEY] then that column 2382251883Speter** is another alias for the rowid. 2383251883Speter** 2384322444Speter** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of 2385322444Speter** the most recent successful [INSERT] into a rowid table or [virtual table] 2386322444Speter** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not 2387366076Scy** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred 2388366076Scy** on the database connection D, then sqlite3_last_insert_rowid(D) returns 2389322444Speter** zero. 2390251883Speter** 2391322444Speter** As well as being set automatically as rows are inserted into database 2392322444Speter** tables, the value returned by this function may be set explicitly by 2393322444Speter** [sqlite3_set_last_insert_rowid()] 2394251883Speter** 2395322444Speter** Some virtual table implementations may INSERT rows into rowid tables as 2396322444Speter** part of committing a transaction (e.g. to flush data accumulated in memory 2397322444Speter** to disk). In this case subsequent calls to this function return the rowid 2398366076Scy** associated with these internal INSERT operations, which leads to 2399322444Speter** unintuitive results. Virtual table implementations that do write to rowid 2400366076Scy** tables in this way can avoid this problem by restoring the original 2401366076Scy** rowid value using [sqlite3_set_last_insert_rowid()] before returning 2402322444Speter** control to the user. 2403322444Speter** 2404366076Scy** ^(If an [INSERT] occurs within a trigger then this routine will 2405366076Scy** return the [rowid] of the inserted row as long as the trigger is 2406366076Scy** running. Once the trigger program ends, the value returned 2407322444Speter** by this routine reverts to what it was before the trigger was fired.)^ 2408322444Speter** 2409251883Speter** ^An [INSERT] that fails due to a constraint violation is not a 2410251883Speter** successful [INSERT] and does not change the value returned by this 2411251883Speter** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, 2412251883Speter** and INSERT OR ABORT make no changes to the return value of this 2413251883Speter** routine when their insertion fails. ^(When INSERT OR REPLACE 2414251883Speter** encounters a constraint violation, it does not fail. The 2415251883Speter** INSERT continues to completion after deleting rows that caused 2416251883Speter** the constraint problem so INSERT OR REPLACE will always change 2417251883Speter** the return value of this interface.)^ 2418251883Speter** 2419251883Speter** ^For the purposes of this routine, an [INSERT] is considered to 2420251883Speter** be successful even if it is subsequently rolled back. 2421251883Speter** 2422251883Speter** This function is accessible to SQL statements via the 2423251883Speter** [last_insert_rowid() SQL function]. 2424251883Speter** 2425251883Speter** If a separate thread performs a new [INSERT] on the same 2426251883Speter** database connection while the [sqlite3_last_insert_rowid()] 2427251883Speter** function is running and thus changes the last insert [rowid], 2428251883Speter** then the value returned by [sqlite3_last_insert_rowid()] is 2429251883Speter** unpredictable and might not equal either the old or the new 2430251883Speter** last insert [rowid]. 2431251883Speter*/ 2432322444SpeterSQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); 2433251883Speter 2434251883Speter/* 2435322444Speter** CAPI3REF: Set the Last Insert Rowid value. 2436322444Speter** METHOD: sqlite3 2437322444Speter** 2438322444Speter** The sqlite3_set_last_insert_rowid(D, R) method allows the application to 2439366076Scy** set the value returned by calling sqlite3_last_insert_rowid(D) to R 2440322444Speter** without inserting a row into the database. 2441322444Speter*/ 2442322444SpeterSQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64); 2443322444Speter 2444322444Speter/* 2445251883Speter** CAPI3REF: Count The Number Of Rows Modified 2446286510Speter** METHOD: sqlite3 2447251883Speter** 2448282328Sbapt** ^This function returns the number of rows modified, inserted or 2449282328Sbapt** deleted by the most recently completed INSERT, UPDATE or DELETE 2450282328Sbapt** statement on the database connection specified by the only parameter. 2451282328Sbapt** ^Executing any other type of SQL statement does not modify the value 2452282328Sbapt** returned by this function. 2453251883Speter** 2454282328Sbapt** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are 2455366076Scy** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], 2456282328Sbapt** [foreign key actions] or [REPLACE] constraint resolution are not counted. 2457366076Scy** 2458366076Scy** Changes to a view that are intercepted by 2459366076Scy** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value 2460366076Scy** returned by sqlite3_changes() immediately after an INSERT, UPDATE or 2461366076Scy** DELETE statement run on a view is always zero. Only changes made to real 2462282328Sbapt** tables are counted. 2463251883Speter** 2464282328Sbapt** Things are more complicated if the sqlite3_changes() function is 2465282328Sbapt** executed while a trigger program is running. This may happen if the 2466282328Sbapt** program uses the [changes() SQL function], or if some other callback 2467282328Sbapt** function invokes sqlite3_changes() directly. Essentially: 2468366076Scy** 2469282328Sbapt** <ul> 2470282328Sbapt** <li> ^(Before entering a trigger program the value returned by 2471366076Scy** sqlite3_changes() function is saved. After the trigger program 2472282328Sbapt** has finished, the original value is restored.)^ 2473366076Scy** 2474366076Scy** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE 2475366076Scy** statement sets the value returned by sqlite3_changes() 2476366076Scy** upon completion as normal. Of course, this value will not include 2477366076Scy** any changes performed by sub-triggers, as the sqlite3_changes() 2478282328Sbapt** value will be saved and restored after each sub-trigger has run.)^ 2479282328Sbapt** </ul> 2480366076Scy** 2481282328Sbapt** ^This means that if the changes() SQL function (or similar) is used 2482366076Scy** by the first INSERT, UPDATE or DELETE statement within a trigger, it 2483282328Sbapt** returns the value as set when the calling statement began executing. 2484366076Scy** ^If it is used by the second or subsequent such statement within a trigger 2485366076Scy** program, the value returned reflects the number of rows modified by the 2486282328Sbapt** previous INSERT, UPDATE or DELETE statement within the same trigger. 2487251883Speter** 2488251883Speter** If a separate thread makes changes on the same database connection 2489251883Speter** while [sqlite3_changes()] is running then the value returned 2490251883Speter** is unpredictable and not meaningful. 2491342292Scy** 2492342292Scy** See also: 2493342292Scy** <ul> 2494342292Scy** <li> the [sqlite3_total_changes()] interface 2495342292Scy** <li> the [count_changes pragma] 2496342292Scy** <li> the [changes() SQL function] 2497342292Scy** <li> the [data_version pragma] 2498342292Scy** </ul> 2499251883Speter*/ 2500322444SpeterSQLITE_API int sqlite3_changes(sqlite3*); 2501251883Speter 2502251883Speter/* 2503251883Speter** CAPI3REF: Total Number Of Rows Modified 2504286510Speter** METHOD: sqlite3 2505251883Speter** 2506282328Sbapt** ^This function returns the total number of rows inserted, modified or 2507282328Sbapt** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed 2508282328Sbapt** since the database connection was opened, including those executed as 2509282328Sbapt** part of trigger programs. ^Executing any other type of SQL statement 2510282328Sbapt** does not affect the value returned by sqlite3_total_changes(). 2511366076Scy** 2512282328Sbapt** ^Changes made as part of [foreign key actions] are included in the 2513282328Sbapt** count, but those made as part of REPLACE constraint resolution are 2514366076Scy** not. ^Changes to a view that are intercepted by INSTEAD OF triggers 2515282328Sbapt** are not counted. 2516342292Scy** 2517346983Scy** The [sqlite3_total_changes(D)] interface only reports the number 2518342292Scy** of rows that changed due to SQL statement run against database 2519342292Scy** connection D. Any changes by other database connections are ignored. 2520342292Scy** To detect changes against a database file from other database 2521342292Scy** connections use the [PRAGMA data_version] command or the 2522342292Scy** [SQLITE_FCNTL_DATA_VERSION] [file control]. 2523366076Scy** 2524251883Speter** If a separate thread makes changes on the same database connection 2525251883Speter** while [sqlite3_total_changes()] is running then the value 2526251883Speter** returned is unpredictable and not meaningful. 2527342292Scy** 2528342292Scy** See also: 2529342292Scy** <ul> 2530342292Scy** <li> the [sqlite3_changes()] interface 2531342292Scy** <li> the [count_changes pragma] 2532342292Scy** <li> the [changes() SQL function] 2533342292Scy** <li> the [data_version pragma] 2534342292Scy** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control] 2535342292Scy** </ul> 2536251883Speter*/ 2537322444SpeterSQLITE_API int sqlite3_total_changes(sqlite3*); 2538251883Speter 2539251883Speter/* 2540251883Speter** CAPI3REF: Interrupt A Long-Running Query 2541286510Speter** METHOD: sqlite3 2542251883Speter** 2543251883Speter** ^This function causes any pending database operation to abort and 2544251883Speter** return at its earliest opportunity. This routine is typically 2545251883Speter** called in response to a user action such as pressing "Cancel" 2546251883Speter** or Ctrl-C where the user wants a long query operation to halt 2547251883Speter** immediately. 2548251883Speter** 2549251883Speter** ^It is safe to call this routine from a thread different from the 2550251883Speter** thread that is currently running the database operation. But it 2551251883Speter** is not safe to call this routine with a [database connection] that 2552251883Speter** is closed or might close before sqlite3_interrupt() returns. 2553251883Speter** 2554251883Speter** ^If an SQL operation is very nearly finished at the time when 2555251883Speter** sqlite3_interrupt() is called, then it might not have an opportunity 2556251883Speter** to be interrupted and might continue to completion. 2557251883Speter** 2558251883Speter** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. 2559251883Speter** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE 2560251883Speter** that is inside an explicit transaction, then the entire transaction 2561251883Speter** will be rolled back automatically. 2562251883Speter** 2563251883Speter** ^The sqlite3_interrupt(D) call is in effect until all currently running 2564251883Speter** SQL statements on [database connection] D complete. ^Any new SQL statements 2565366076Scy** that are started after the sqlite3_interrupt() call and before the 2566361456Scy** running statement count reaches zero are interrupted as if they had been 2567251883Speter** running prior to the sqlite3_interrupt() call. ^New SQL statements 2568251883Speter** that are started after the running statement count reaches zero are 2569251883Speter** not effected by the sqlite3_interrupt(). 2570251883Speter** ^A call to sqlite3_interrupt(D) that occurs when there are no running 2571251883Speter** SQL statements is a no-op and has no effect on SQL statements 2572251883Speter** that are started after the sqlite3_interrupt() call returns. 2573251883Speter*/ 2574322444SpeterSQLITE_API void sqlite3_interrupt(sqlite3*); 2575251883Speter 2576251883Speter/* 2577251883Speter** CAPI3REF: Determine If An SQL Statement Is Complete 2578251883Speter** 2579251883Speter** These routines are useful during command-line input to determine if the 2580251883Speter** currently entered text seems to form a complete SQL statement or 2581251883Speter** if additional input is needed before sending the text into 2582251883Speter** SQLite for parsing. ^These routines return 1 if the input string 2583251883Speter** appears to be a complete SQL statement. ^A statement is judged to be 2584251883Speter** complete if it ends with a semicolon token and is not a prefix of a 2585251883Speter** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within 2586251883Speter** string literals or quoted identifier names or comments are not 2587251883Speter** independent tokens (they are part of the token in which they are 2588251883Speter** embedded) and thus do not count as a statement terminator. ^Whitespace 2589251883Speter** and comments that follow the final semicolon are ignored. 2590251883Speter** 2591251883Speter** ^These routines return 0 if the statement is incomplete. ^If a 2592251883Speter** memory allocation fails, then SQLITE_NOMEM is returned. 2593251883Speter** 2594251883Speter** ^These routines do not parse the SQL statements thus 2595251883Speter** will not detect syntactically incorrect SQL. 2596251883Speter** 2597366076Scy** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior 2598251883Speter** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked 2599251883Speter** automatically by sqlite3_complete16(). If that initialization fails, 2600251883Speter** then the return value from sqlite3_complete16() will be non-zero 2601251883Speter** regardless of whether or not the input SQL is complete.)^ 2602251883Speter** 2603251883Speter** The input to [sqlite3_complete()] must be a zero-terminated 2604251883Speter** UTF-8 string. 2605251883Speter** 2606251883Speter** The input to [sqlite3_complete16()] must be a zero-terminated 2607251883Speter** UTF-16 string in native byte order. 2608251883Speter*/ 2609322444SpeterSQLITE_API int sqlite3_complete(const char *sql); 2610322444SpeterSQLITE_API int sqlite3_complete16(const void *sql); 2611251883Speter 2612251883Speter/* 2613251883Speter** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors 2614282328Sbapt** KEYWORDS: {busy-handler callback} {busy handler} 2615286510Speter** METHOD: sqlite3 2616251883Speter** 2617274884Sbapt** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X 2618274884Sbapt** that might be invoked with argument P whenever 2619274884Sbapt** an attempt is made to access a database table associated with 2620274884Sbapt** [database connection] D when another thread 2621274884Sbapt** or process has the table locked. 2622274884Sbapt** The sqlite3_busy_handler() interface is used to implement 2623274884Sbapt** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout]. 2624251883Speter** 2625274884Sbapt** ^If the busy callback is NULL, then [SQLITE_BUSY] 2626251883Speter** is returned immediately upon encountering the lock. ^If the busy callback 2627251883Speter** is not NULL, then the callback might be invoked with two arguments. 2628251883Speter** 2629251883Speter** ^The first argument to the busy handler is a copy of the void* pointer which 2630251883Speter** is the third argument to sqlite3_busy_handler(). ^The second argument to 2631251883Speter** the busy handler callback is the number of times that the busy handler has 2632282328Sbapt** been invoked previously for the same locking event. ^If the 2633251883Speter** busy callback returns 0, then no additional attempts are made to 2634274884Sbapt** access the database and [SQLITE_BUSY] is returned 2635274884Sbapt** to the application. 2636251883Speter** ^If the callback returns non-zero, then another attempt 2637274884Sbapt** is made to access the database and the cycle repeats. 2638251883Speter** 2639251883Speter** The presence of a busy handler does not guarantee that it will be invoked 2640251883Speter** when there is lock contention. ^If SQLite determines that invoking the busy 2641251883Speter** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] 2642366076Scy** to the application instead of invoking the 2643274884Sbapt** busy handler. 2644251883Speter** Consider a scenario where one process is holding a read lock that 2645251883Speter** it is trying to promote to a reserved lock and 2646251883Speter** a second process is holding a reserved lock that it is trying 2647251883Speter** to promote to an exclusive lock. The first process cannot proceed 2648251883Speter** because it is blocked by the second and the second process cannot 2649251883Speter** proceed because it is blocked by the first. If both processes 2650251883Speter** invoke the busy handlers, neither will make any progress. Therefore, 2651251883Speter** SQLite returns [SQLITE_BUSY] for the first process, hoping that this 2652251883Speter** will induce the first process to release its read lock and allow 2653251883Speter** the second process to proceed. 2654251883Speter** 2655251883Speter** ^The default busy callback is NULL. 2656251883Speter** 2657251883Speter** ^(There can only be a single busy handler defined for each 2658251883Speter** [database connection]. Setting a new busy handler clears any 2659251883Speter** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()] 2660274884Sbapt** or evaluating [PRAGMA busy_timeout=N] will change the 2661274884Sbapt** busy handler and thus clear any previously set busy handler. 2662251883Speter** 2663251883Speter** The busy callback should not take any actions which modify the 2664274884Sbapt** database connection that invoked the busy handler. In other words, 2665274884Sbapt** the busy handler is not reentrant. Any such actions 2666251883Speter** result in undefined behavior. 2667366076Scy** 2668251883Speter** A busy handler must not close the database connection 2669251883Speter** or [prepared statement] that invoked the busy handler. 2670251883Speter*/ 2671322444SpeterSQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*); 2672251883Speter 2673251883Speter/* 2674251883Speter** CAPI3REF: Set A Busy Timeout 2675286510Speter** METHOD: sqlite3 2676251883Speter** 2677251883Speter** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps 2678251883Speter** for a specified amount of time when a table is locked. ^The handler 2679251883Speter** will sleep multiple times until at least "ms" milliseconds of sleeping 2680251883Speter** have accumulated. ^After at least "ms" milliseconds of sleeping, 2681251883Speter** the handler returns 0 which causes [sqlite3_step()] to return 2682274884Sbapt** [SQLITE_BUSY]. 2683251883Speter** 2684251883Speter** ^Calling this routine with an argument less than or equal to zero 2685251883Speter** turns off all busy handlers. 2686251883Speter** 2687251883Speter** ^(There can only be a single busy handler for a particular 2688274884Sbapt** [database connection] at any given moment. If another busy handler 2689251883Speter** was defined (using [sqlite3_busy_handler()]) prior to calling 2690251883Speter** this routine, that other busy handler is cleared.)^ 2691274884Sbapt** 2692274884Sbapt** See also: [PRAGMA busy_timeout] 2693251883Speter*/ 2694322444SpeterSQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms); 2695251883Speter 2696251883Speter/* 2697251883Speter** CAPI3REF: Convenience Routines For Running Queries 2698286510Speter** METHOD: sqlite3 2699251883Speter** 2700251883Speter** This is a legacy interface that is preserved for backwards compatibility. 2701251883Speter** Use of this interface is not recommended. 2702251883Speter** 2703251883Speter** Definition: A <b>result table</b> is memory data structure created by the 2704251883Speter** [sqlite3_get_table()] interface. A result table records the 2705251883Speter** complete query results from one or more queries. 2706251883Speter** 2707251883Speter** The table conceptually has a number of rows and columns. But 2708251883Speter** these numbers are not part of the result table itself. These 2709251883Speter** numbers are obtained separately. Let N be the number of rows 2710251883Speter** and M be the number of columns. 2711251883Speter** 2712251883Speter** A result table is an array of pointers to zero-terminated UTF-8 strings. 2713251883Speter** There are (N+1)*M elements in the array. The first M pointers point 2714251883Speter** to zero-terminated strings that contain the names of the columns. 2715251883Speter** The remaining entries all point to query results. NULL values result 2716251883Speter** in NULL pointers. All other values are in their UTF-8 zero-terminated 2717251883Speter** string representation as returned by [sqlite3_column_text()]. 2718251883Speter** 2719251883Speter** A result table might consist of one or more memory allocations. 2720251883Speter** It is not safe to pass a result table directly to [sqlite3_free()]. 2721251883Speter** A result table should be deallocated using [sqlite3_free_table()]. 2722251883Speter** 2723251883Speter** ^(As an example of the result table format, suppose a query result 2724251883Speter** is as follows: 2725251883Speter** 2726251883Speter** <blockquote><pre> 2727251883Speter** Name | Age 2728251883Speter** ----------------------- 2729251883Speter** Alice | 43 2730251883Speter** Bob | 28 2731251883Speter** Cindy | 21 2732251883Speter** </pre></blockquote> 2733251883Speter** 2734361456Scy** There are two columns (M==2) and three rows (N==3). Thus the 2735251883Speter** result table has 8 entries. Suppose the result table is stored 2736361456Scy** in an array named azResult. Then azResult holds this content: 2737251883Speter** 2738251883Speter** <blockquote><pre> 2739251883Speter** azResult[0] = "Name"; 2740251883Speter** azResult[1] = "Age"; 2741251883Speter** azResult[2] = "Alice"; 2742251883Speter** azResult[3] = "43"; 2743251883Speter** azResult[4] = "Bob"; 2744251883Speter** azResult[5] = "28"; 2745251883Speter** azResult[6] = "Cindy"; 2746251883Speter** azResult[7] = "21"; 2747251883Speter** </pre></blockquote>)^ 2748251883Speter** 2749251883Speter** ^The sqlite3_get_table() function evaluates one or more 2750251883Speter** semicolon-separated SQL statements in the zero-terminated UTF-8 2751251883Speter** string of its 2nd parameter and returns a result table to the 2752251883Speter** pointer given in its 3rd parameter. 2753251883Speter** 2754251883Speter** After the application has finished with the result from sqlite3_get_table(), 2755251883Speter** it must pass the result table pointer to sqlite3_free_table() in order to 2756251883Speter** release the memory that was malloced. Because of the way the 2757251883Speter** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling 2758251883Speter** function must not try to call [sqlite3_free()] directly. Only 2759251883Speter** [sqlite3_free_table()] is able to release the memory properly and safely. 2760251883Speter** 2761251883Speter** The sqlite3_get_table() interface is implemented as a wrapper around 2762251883Speter** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access 2763251883Speter** to any internal data structures of SQLite. It uses only the public 2764251883Speter** interface defined here. As a consequence, errors that occur in the 2765251883Speter** wrapper layer outside of the internal [sqlite3_exec()] call are not 2766251883Speter** reflected in subsequent calls to [sqlite3_errcode()] or 2767251883Speter** [sqlite3_errmsg()]. 2768251883Speter*/ 2769322444SpeterSQLITE_API int sqlite3_get_table( 2770251883Speter sqlite3 *db, /* An open database */ 2771251883Speter const char *zSql, /* SQL to be evaluated */ 2772251883Speter char ***pazResult, /* Results of the query */ 2773251883Speter int *pnRow, /* Number of result rows written here */ 2774251883Speter int *pnColumn, /* Number of result columns written here */ 2775251883Speter char **pzErrmsg /* Error msg written here */ 2776251883Speter); 2777322444SpeterSQLITE_API void sqlite3_free_table(char **result); 2778251883Speter 2779251883Speter/* 2780251883Speter** CAPI3REF: Formatted String Printing Functions 2781251883Speter** 2782251883Speter** These routines are work-alikes of the "printf()" family of functions 2783251883Speter** from the standard C library. 2784342292Scy** These routines understand most of the common formatting options from 2785366076Scy** the standard library printf() 2786342292Scy** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]). 2787342292Scy** See the [built-in printf()] documentation for details. 2788251883Speter** 2789251883Speter** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their 2790342292Scy** results into memory obtained from [sqlite3_malloc64()]. 2791251883Speter** The strings returned by these two routines should be 2792251883Speter** released by [sqlite3_free()]. ^Both routines return a 2793342292Scy** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough 2794251883Speter** memory to hold the resulting string. 2795251883Speter** 2796251883Speter** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from 2797251883Speter** the standard C library. The result is written into the 2798251883Speter** buffer supplied as the second parameter whose size is given by 2799251883Speter** the first parameter. Note that the order of the 2800251883Speter** first two parameters is reversed from snprintf().)^ This is an 2801251883Speter** historical accident that cannot be fixed without breaking 2802251883Speter** backwards compatibility. ^(Note also that sqlite3_snprintf() 2803251883Speter** returns a pointer to its buffer instead of the number of 2804251883Speter** characters actually written into the buffer.)^ We admit that 2805251883Speter** the number of characters written would be a more useful return 2806251883Speter** value but we cannot change the implementation of sqlite3_snprintf() 2807251883Speter** now without breaking compatibility. 2808251883Speter** 2809251883Speter** ^As long as the buffer size is greater than zero, sqlite3_snprintf() 2810251883Speter** guarantees that the buffer is always zero-terminated. ^The first 2811251883Speter** parameter "n" is the total size of the buffer, including space for 2812251883Speter** the zero terminator. So the longest string that can be completely 2813251883Speter** written will be n-1 characters. 2814251883Speter** 2815251883Speter** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf(). 2816251883Speter** 2817342292Scy** See also: [built-in printf()], [printf() SQL function] 2818251883Speter*/ 2819322444SpeterSQLITE_API char *sqlite3_mprintf(const char*,...); 2820322444SpeterSQLITE_API char *sqlite3_vmprintf(const char*, va_list); 2821322444SpeterSQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...); 2822322444SpeterSQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list); 2823251883Speter 2824251883Speter/* 2825251883Speter** CAPI3REF: Memory Allocation Subsystem 2826251883Speter** 2827251883Speter** The SQLite core uses these three routines for all of its own 2828251883Speter** internal memory allocation needs. "Core" in the previous sentence 2829361456Scy** does not include operating-system specific [VFS] implementation. The 2830251883Speter** Windows VFS uses native malloc() and free() for some operations. 2831251883Speter** 2832251883Speter** ^The sqlite3_malloc() routine returns a pointer to a block 2833251883Speter** of memory at least N bytes in length, where N is the parameter. 2834251883Speter** ^If sqlite3_malloc() is unable to obtain sufficient free 2835251883Speter** memory, it returns a NULL pointer. ^If the parameter N to 2836251883Speter** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns 2837251883Speter** a NULL pointer. 2838251883Speter** 2839274884Sbapt** ^The sqlite3_malloc64(N) routine works just like 2840274884Sbapt** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead 2841274884Sbapt** of a signed 32-bit integer. 2842274884Sbapt** 2843251883Speter** ^Calling sqlite3_free() with a pointer previously returned 2844251883Speter** by sqlite3_malloc() or sqlite3_realloc() releases that memory so 2845251883Speter** that it might be reused. ^The sqlite3_free() routine is 2846251883Speter** a no-op if is called with a NULL pointer. Passing a NULL pointer 2847251883Speter** to sqlite3_free() is harmless. After being freed, memory 2848251883Speter** should neither be read nor written. Even reading previously freed 2849251883Speter** memory might result in a segmentation fault or other severe error. 2850251883Speter** Memory corruption, a segmentation fault, or other severe error 2851251883Speter** might result if sqlite3_free() is called with a non-NULL pointer that 2852251883Speter** was not obtained from sqlite3_malloc() or sqlite3_realloc(). 2853251883Speter** 2854274884Sbapt** ^The sqlite3_realloc(X,N) interface attempts to resize a 2855274884Sbapt** prior memory allocation X to be at least N bytes. 2856274884Sbapt** ^If the X parameter to sqlite3_realloc(X,N) 2857251883Speter** is a NULL pointer then its behavior is identical to calling 2858274884Sbapt** sqlite3_malloc(N). 2859274884Sbapt** ^If the N parameter to sqlite3_realloc(X,N) is zero or 2860251883Speter** negative then the behavior is exactly the same as calling 2861274884Sbapt** sqlite3_free(X). 2862274884Sbapt** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation 2863274884Sbapt** of at least N bytes in size or NULL if insufficient memory is available. 2864251883Speter** ^If M is the size of the prior allocation, then min(N,M) bytes 2865251883Speter** of the prior allocation are copied into the beginning of buffer returned 2866274884Sbapt** by sqlite3_realloc(X,N) and the prior allocation is freed. 2867274884Sbapt** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the 2868274884Sbapt** prior allocation is not freed. 2869251883Speter** 2870274884Sbapt** ^The sqlite3_realloc64(X,N) interfaces works the same as 2871274884Sbapt** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead 2872274884Sbapt** of a 32-bit signed integer. 2873274884Sbapt** 2874274884Sbapt** ^If X is a memory allocation previously obtained from sqlite3_malloc(), 2875274884Sbapt** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then 2876274884Sbapt** sqlite3_msize(X) returns the size of that memory allocation in bytes. 2877274884Sbapt** ^The value returned by sqlite3_msize(X) might be larger than the number 2878274884Sbapt** of bytes requested when X was allocated. ^If X is a NULL pointer then 2879274884Sbapt** sqlite3_msize(X) returns zero. If X points to something that is not 2880274884Sbapt** the beginning of memory allocation, or if it points to a formerly 2881274884Sbapt** valid memory allocation that has now been freed, then the behavior 2882274884Sbapt** of sqlite3_msize(X) is undefined and possibly harmful. 2883274884Sbapt** 2884274884Sbapt** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(), 2885274884Sbapt** sqlite3_malloc64(), and sqlite3_realloc64() 2886251883Speter** is always aligned to at least an 8 byte boundary, or to a 2887251883Speter** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time 2888251883Speter** option is used. 2889251883Speter** 2890251883Speter** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] 2891251883Speter** must be either NULL or else pointers obtained from a prior 2892251883Speter** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have 2893251883Speter** not yet been released. 2894251883Speter** 2895251883Speter** The application must not read or write any part of 2896251883Speter** a block of memory after it has been released using 2897251883Speter** [sqlite3_free()] or [sqlite3_realloc()]. 2898251883Speter*/ 2899322444SpeterSQLITE_API void *sqlite3_malloc(int); 2900322444SpeterSQLITE_API void *sqlite3_malloc64(sqlite3_uint64); 2901322444SpeterSQLITE_API void *sqlite3_realloc(void*, int); 2902322444SpeterSQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64); 2903322444SpeterSQLITE_API void sqlite3_free(void*); 2904322444SpeterSQLITE_API sqlite3_uint64 sqlite3_msize(void*); 2905251883Speter 2906251883Speter/* 2907251883Speter** CAPI3REF: Memory Allocator Statistics 2908251883Speter** 2909251883Speter** SQLite provides these two interfaces for reporting on the status 2910251883Speter** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] 2911251883Speter** routines, which form the built-in memory allocation subsystem. 2912251883Speter** 2913251883Speter** ^The [sqlite3_memory_used()] routine returns the number of bytes 2914251883Speter** of memory currently outstanding (malloced but not freed). 2915251883Speter** ^The [sqlite3_memory_highwater()] routine returns the maximum 2916251883Speter** value of [sqlite3_memory_used()] since the high-water mark 2917251883Speter** was last reset. ^The values returned by [sqlite3_memory_used()] and 2918251883Speter** [sqlite3_memory_highwater()] include any overhead 2919251883Speter** added by SQLite in its implementation of [sqlite3_malloc()], 2920251883Speter** but not overhead added by the any underlying system library 2921251883Speter** routines that [sqlite3_malloc()] may call. 2922251883Speter** 2923251883Speter** ^The memory high-water mark is reset to the current value of 2924251883Speter** [sqlite3_memory_used()] if and only if the parameter to 2925251883Speter** [sqlite3_memory_highwater()] is true. ^The value returned 2926251883Speter** by [sqlite3_memory_highwater(1)] is the high-water mark 2927251883Speter** prior to the reset. 2928251883Speter*/ 2929322444SpeterSQLITE_API sqlite3_int64 sqlite3_memory_used(void); 2930322444SpeterSQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag); 2931251883Speter 2932251883Speter/* 2933251883Speter** CAPI3REF: Pseudo-Random Number Generator 2934251883Speter** 2935251883Speter** SQLite contains a high-quality pseudo-random number generator (PRNG) used to 2936251883Speter** select random [ROWID | ROWIDs] when inserting new records into a table that 2937251883Speter** already uses the largest possible [ROWID]. The PRNG is also used for 2938361456Scy** the built-in random() and randomblob() SQL functions. This interface allows 2939251883Speter** applications to access the same PRNG for other purposes. 2940251883Speter** 2941251883Speter** ^A call to this routine stores N bytes of randomness into buffer P. 2942282328Sbapt** ^The P parameter can be a NULL pointer. 2943251883Speter** 2944269851Speter** ^If this routine has not been previously called or if the previous 2945282328Sbapt** call had N less than one or a NULL pointer for P, then the PRNG is 2946282328Sbapt** seeded using randomness obtained from the xRandomness method of 2947282328Sbapt** the default [sqlite3_vfs] object. 2948282328Sbapt** ^If the previous call to this routine had an N of 1 or more and a 2949282328Sbapt** non-NULL P then the pseudo-randomness is generated 2950251883Speter** internally and without recourse to the [sqlite3_vfs] xRandomness 2951251883Speter** method. 2952251883Speter*/ 2953322444SpeterSQLITE_API void sqlite3_randomness(int N, void *P); 2954251883Speter 2955251883Speter/* 2956251883Speter** CAPI3REF: Compile-Time Authorization Callbacks 2957286510Speter** METHOD: sqlite3 2958322444Speter** KEYWORDS: {authorizer callback} 2959251883Speter** 2960251883Speter** ^This routine registers an authorizer callback with a particular 2961251883Speter** [database connection], supplied in the first argument. 2962251883Speter** ^The authorizer callback is invoked as SQL statements are being compiled 2963251883Speter** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], 2964322444Speter** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()], 2965322444Speter** and [sqlite3_prepare16_v3()]. ^At various 2966251883Speter** points during the compilation process, as logic is being created 2967251883Speter** to perform various actions, the authorizer callback is invoked to 2968251883Speter** see if those actions are allowed. ^The authorizer callback should 2969251883Speter** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the 2970251883Speter** specific action but allow the SQL statement to continue to be 2971251883Speter** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be 2972251883Speter** rejected with an error. ^If the authorizer callback returns 2973251883Speter** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] 2974251883Speter** then the [sqlite3_prepare_v2()] or equivalent call that triggered 2975251883Speter** the authorizer will fail with an error message. 2976251883Speter** 2977251883Speter** When the callback returns [SQLITE_OK], that means the operation 2978251883Speter** requested is ok. ^When the callback returns [SQLITE_DENY], the 2979251883Speter** [sqlite3_prepare_v2()] or equivalent call that triggered the 2980251883Speter** authorizer will fail with an error message explaining that 2981366076Scy** access is denied. 2982251883Speter** 2983251883Speter** ^The first parameter to the authorizer callback is a copy of the third 2984251883Speter** parameter to the sqlite3_set_authorizer() interface. ^The second parameter 2985251883Speter** to the callback is an integer [SQLITE_COPY | action code] that specifies 2986251883Speter** the particular action to be authorized. ^The third through sixth parameters 2987322444Speter** to the callback are either NULL pointers or zero-terminated strings 2988322444Speter** that contain additional details about the action to be authorized. 2989322444Speter** Applications must always be prepared to encounter a NULL pointer in any 2990322444Speter** of the third through the sixth parameters of the authorization callback. 2991251883Speter** 2992251883Speter** ^If the action code is [SQLITE_READ] 2993251883Speter** and the callback returns [SQLITE_IGNORE] then the 2994251883Speter** [prepared statement] statement is constructed to substitute 2995251883Speter** a NULL value in place of the table column that would have 2996251883Speter** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] 2997251883Speter** return can be used to deny an untrusted user access to individual 2998251883Speter** columns of a table. 2999322444Speter** ^When a table is referenced by a [SELECT] but no column values are 3000322444Speter** extracted from that table (for example in a query like 3001322444Speter** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback 3002322444Speter** is invoked once for that table with a column name that is an empty string. 3003251883Speter** ^If the action code is [SQLITE_DELETE] and the callback returns 3004251883Speter** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the 3005251883Speter** [truncate optimization] is disabled and all rows are deleted individually. 3006251883Speter** 3007251883Speter** An authorizer is used when [sqlite3_prepare | preparing] 3008251883Speter** SQL statements from an untrusted source, to ensure that the SQL statements 3009251883Speter** do not try to access data they are not allowed to see, or that they do not 3010251883Speter** try to execute malicious statements that damage the database. For 3011251883Speter** example, an application may allow a user to enter arbitrary 3012251883Speter** SQL queries for evaluation by a database. But the application does 3013251883Speter** not want the user to be able to make arbitrary changes to the 3014251883Speter** database. An authorizer could then be put in place while the 3015251883Speter** user-entered SQL is being [sqlite3_prepare | prepared] that 3016251883Speter** disallows everything except [SELECT] statements. 3017251883Speter** 3018251883Speter** Applications that need to process SQL from untrusted sources 3019251883Speter** might also consider lowering resource limits using [sqlite3_limit()] 3020251883Speter** and limiting database size using the [max_page_count] [PRAGMA] 3021251883Speter** in addition to using an authorizer. 3022251883Speter** 3023251883Speter** ^(Only a single authorizer can be in place on a database connection 3024251883Speter** at a time. Each call to sqlite3_set_authorizer overrides the 3025251883Speter** previous call.)^ ^Disable the authorizer by installing a NULL callback. 3026251883Speter** The authorizer is disabled by default. 3027251883Speter** 3028251883Speter** The authorizer callback must not do anything that will modify 3029251883Speter** the database connection that invoked the authorizer callback. 3030251883Speter** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 3031251883Speter** database connections for the meaning of "modify" in this paragraph. 3032251883Speter** 3033251883Speter** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the 3034366076Scy** statement might be re-prepared during [sqlite3_step()] due to a 3035251883Speter** schema change. Hence, the application should ensure that the 3036251883Speter** correct authorizer callback remains in place during the [sqlite3_step()]. 3037251883Speter** 3038251883Speter** ^Note that the authorizer callback is invoked only during 3039251883Speter** [sqlite3_prepare()] or its variants. Authorization is not 3040251883Speter** performed during statement evaluation in [sqlite3_step()], unless 3041251883Speter** as stated in the previous paragraph, sqlite3_step() invokes 3042251883Speter** sqlite3_prepare_v2() to reprepare a statement after a schema change. 3043251883Speter*/ 3044322444SpeterSQLITE_API int sqlite3_set_authorizer( 3045251883Speter sqlite3*, 3046251883Speter int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), 3047251883Speter void *pUserData 3048251883Speter); 3049251883Speter 3050251883Speter/* 3051251883Speter** CAPI3REF: Authorizer Return Codes 3052251883Speter** 3053251883Speter** The [sqlite3_set_authorizer | authorizer callback function] must 3054251883Speter** return either [SQLITE_OK] or one of these two constants in order 3055251883Speter** to signal SQLite whether or not the action is permitted. See the 3056251883Speter** [sqlite3_set_authorizer | authorizer documentation] for additional 3057251883Speter** information. 3058251883Speter** 3059274884Sbapt** Note that SQLITE_IGNORE is also used as a [conflict resolution mode] 3060274884Sbapt** returned from the [sqlite3_vtab_on_conflict()] interface. 3061251883Speter*/ 3062251883Speter#define SQLITE_DENY 1 /* Abort the SQL statement with an error */ 3063251883Speter#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ 3064251883Speter 3065251883Speter/* 3066251883Speter** CAPI3REF: Authorizer Action Codes 3067251883Speter** 3068251883Speter** The [sqlite3_set_authorizer()] interface registers a callback function 3069251883Speter** that is invoked to authorize certain SQL statement actions. The 3070251883Speter** second parameter to the callback is an integer code that specifies 3071251883Speter** what action is being authorized. These are the integer action codes that 3072251883Speter** the authorizer callback may be passed. 3073251883Speter** 3074251883Speter** These action code values signify what kind of operation is to be 3075251883Speter** authorized. The 3rd and 4th parameters to the authorization 3076251883Speter** callback function will be parameters or NULL depending on which of these 3077251883Speter** codes is used as the second parameter. ^(The 5th parameter to the 3078251883Speter** authorizer callback is the name of the database ("main", "temp", 3079251883Speter** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback 3080251883Speter** is the name of the inner-most trigger or view that is responsible for 3081251883Speter** the access attempt or NULL if this access attempt is directly from 3082251883Speter** top-level SQL code. 3083251883Speter*/ 3084251883Speter/******************************************* 3rd ************ 4th ***********/ 3085251883Speter#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ 3086251883Speter#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ 3087251883Speter#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ 3088251883Speter#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ 3089251883Speter#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ 3090251883Speter#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ 3091251883Speter#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ 3092251883Speter#define SQLITE_CREATE_VIEW 8 /* View Name NULL */ 3093251883Speter#define SQLITE_DELETE 9 /* Table Name NULL */ 3094251883Speter#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ 3095251883Speter#define SQLITE_DROP_TABLE 11 /* Table Name NULL */ 3096251883Speter#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ 3097251883Speter#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ 3098251883Speter#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ 3099251883Speter#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ 3100251883Speter#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ 3101251883Speter#define SQLITE_DROP_VIEW 17 /* View Name NULL */ 3102251883Speter#define SQLITE_INSERT 18 /* Table Name NULL */ 3103251883Speter#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ 3104251883Speter#define SQLITE_READ 20 /* Table Name Column Name */ 3105251883Speter#define SQLITE_SELECT 21 /* NULL NULL */ 3106251883Speter#define SQLITE_TRANSACTION 22 /* Operation NULL */ 3107251883Speter#define SQLITE_UPDATE 23 /* Table Name Column Name */ 3108251883Speter#define SQLITE_ATTACH 24 /* Filename NULL */ 3109251883Speter#define SQLITE_DETACH 25 /* Database Name NULL */ 3110251883Speter#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ 3111251883Speter#define SQLITE_REINDEX 27 /* Index Name NULL */ 3112251883Speter#define SQLITE_ANALYZE 28 /* Table Name NULL */ 3113251883Speter#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ 3114251883Speter#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ 3115251883Speter#define SQLITE_FUNCTION 31 /* NULL Function Name */ 3116251883Speter#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */ 3117251883Speter#define SQLITE_COPY 0 /* No longer used */ 3118269851Speter#define SQLITE_RECURSIVE 33 /* NULL NULL */ 3119251883Speter 3120251883Speter/* 3121251883Speter** CAPI3REF: Tracing And Profiling Functions 3122286510Speter** METHOD: sqlite3 3123251883Speter** 3124305002Scy** These routines are deprecated. Use the [sqlite3_trace_v2()] interface 3125305002Scy** instead of the routines described here. 3126305002Scy** 3127251883Speter** These routines register callback functions that can be used for 3128251883Speter** tracing and profiling the execution of SQL statements. 3129251883Speter** 3130251883Speter** ^The callback function registered by sqlite3_trace() is invoked at 3131251883Speter** various times when an SQL statement is being run by [sqlite3_step()]. 3132251883Speter** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the 3133251883Speter** SQL statement text as the statement first begins executing. 3134251883Speter** ^(Additional sqlite3_trace() callbacks might occur 3135251883Speter** as each triggered subprogram is entered. The callbacks for triggers 3136251883Speter** contain a UTF-8 SQL comment that identifies the trigger.)^ 3137251883Speter** 3138251883Speter** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit 3139251883Speter** the length of [bound parameter] expansion in the output of sqlite3_trace(). 3140251883Speter** 3141251883Speter** ^The callback function registered by sqlite3_profile() is invoked 3142251883Speter** as each SQL statement finishes. ^The profile callback contains 3143251883Speter** the original statement text and an estimate of wall-clock time 3144251883Speter** of how long that statement took to run. ^The profile callback 3145251883Speter** time is in units of nanoseconds, however the current implementation 3146251883Speter** is only capable of millisecond resolution so the six least significant 3147251883Speter** digits in the time are meaningless. Future versions of SQLite 3148346442Scy** might provide greater resolution on the profiler callback. Invoking 3149346442Scy** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the 3150346442Scy** profile callback. 3151251883Speter*/ 3152322444SpeterSQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*, 3153305002Scy void(*xTrace)(void*,const char*), void*); 3154322444SpeterSQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*, 3155251883Speter void(*xProfile)(void*,const char*,sqlite3_uint64), void*); 3156251883Speter 3157251883Speter/* 3158305002Scy** CAPI3REF: SQL Trace Event Codes 3159305002Scy** KEYWORDS: SQLITE_TRACE 3160305002Scy** 3161305002Scy** These constants identify classes of events that can be monitored 3162342292Scy** using the [sqlite3_trace_v2()] tracing logic. The M argument 3163342292Scy** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of 3164305002Scy** the following constants. ^The first argument to the trace callback 3165305002Scy** is one of the following constants. 3166305002Scy** 3167305002Scy** New tracing constants may be added in future releases. 3168305002Scy** 3169305002Scy** ^A trace callback has four arguments: xCallback(T,C,P,X). 3170305002Scy** ^The T argument is one of the integer type codes above. 3171305002Scy** ^The C argument is a copy of the context pointer passed in as the 3172305002Scy** fourth argument to [sqlite3_trace_v2()]. 3173305002Scy** The P and X arguments are pointers whose meanings depend on T. 3174305002Scy** 3175305002Scy** <dl> 3176305002Scy** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt> 3177305002Scy** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement 3178305002Scy** first begins running and possibly at other times during the 3179305002Scy** execution of the prepared statement, such as at the start of each 3180305002Scy** trigger subprogram. ^The P argument is a pointer to the 3181305002Scy** [prepared statement]. ^The X argument is a pointer to a string which 3182366076Scy** is the unexpanded SQL text of the prepared statement or an SQL comment 3183305002Scy** that indicates the invocation of a trigger. ^The callback can compute 3184305002Scy** the same text that would have been returned by the legacy [sqlite3_trace()] 3185305002Scy** interface by using the X argument when X begins with "--" and invoking 3186305002Scy** [sqlite3_expanded_sql(P)] otherwise. 3187305002Scy** 3188305002Scy** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt> 3189305002Scy** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same 3190305002Scy** information as is provided by the [sqlite3_profile()] callback. 3191305002Scy** ^The P argument is a pointer to the [prepared statement] and the 3192305002Scy** X argument points to a 64-bit integer which is the estimated of 3193305002Scy** the number of nanosecond that the prepared statement took to run. 3194305002Scy** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes. 3195305002Scy** 3196305002Scy** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt> 3197305002Scy** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared 3198366076Scy** statement generates a single row of result. 3199305002Scy** ^The P argument is a pointer to the [prepared statement] and the 3200305002Scy** X argument is unused. 3201305002Scy** 3202305002Scy** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt> 3203305002Scy** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database 3204305002Scy** connection closes. 3205305002Scy** ^The P argument is a pointer to the [database connection] object 3206305002Scy** and the X argument is unused. 3207305002Scy** </dl> 3208305002Scy*/ 3209305002Scy#define SQLITE_TRACE_STMT 0x01 3210305002Scy#define SQLITE_TRACE_PROFILE 0x02 3211305002Scy#define SQLITE_TRACE_ROW 0x04 3212305002Scy#define SQLITE_TRACE_CLOSE 0x08 3213305002Scy 3214305002Scy/* 3215305002Scy** CAPI3REF: SQL Trace Hook 3216305002Scy** METHOD: sqlite3 3217305002Scy** 3218305002Scy** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback 3219305002Scy** function X against [database connection] D, using property mask M 3220305002Scy** and context pointer P. ^If the X callback is 3221305002Scy** NULL or if the M mask is zero, then tracing is disabled. The 3222305002Scy** M argument should be the bitwise OR-ed combination of 3223305002Scy** zero or more [SQLITE_TRACE] constants. 3224305002Scy** 3225366076Scy** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides 3226305002Scy** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2(). 3227305002Scy** 3228366076Scy** ^The X callback is invoked whenever any of the events identified by 3229305002Scy** mask M occur. ^The integer return value from the callback is currently 3230305002Scy** ignored, though this may change in future releases. Callback 3231305002Scy** implementations should return zero to ensure future compatibility. 3232305002Scy** 3233305002Scy** ^A trace callback is invoked with four arguments: callback(T,C,P,X). 3234305002Scy** ^The T argument is one of the [SQLITE_TRACE] 3235305002Scy** constants to indicate why the callback was invoked. 3236305002Scy** ^The C argument is a copy of the context pointer. 3237305002Scy** The P and X arguments are pointers whose meanings depend on T. 3238305002Scy** 3239305002Scy** The sqlite3_trace_v2() interface is intended to replace the legacy 3240305002Scy** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which 3241305002Scy** are deprecated. 3242305002Scy*/ 3243322444SpeterSQLITE_API int sqlite3_trace_v2( 3244305002Scy sqlite3*, 3245305002Scy unsigned uMask, 3246305002Scy int(*xCallback)(unsigned,void*,void*,void*), 3247305002Scy void *pCtx 3248305002Scy); 3249305002Scy 3250305002Scy/* 3251251883Speter** CAPI3REF: Query Progress Callbacks 3252286510Speter** METHOD: sqlite3 3253251883Speter** 3254251883Speter** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback 3255251883Speter** function X to be invoked periodically during long running calls to 3256251883Speter** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for 3257251883Speter** database connection D. An example use for this 3258251883Speter** interface is to keep a GUI updated during a large query. 3259251883Speter** 3260366076Scy** ^The parameter P is passed through as the only parameter to the 3261366076Scy** callback function X. ^The parameter N is the approximate number of 3262251883Speter** [virtual machine instructions] that are evaluated between successive 3263269851Speter** invocations of the callback X. ^If N is less than one then the progress 3264269851Speter** handler is disabled. 3265251883Speter** 3266251883Speter** ^Only a single progress handler may be defined at one time per 3267251883Speter** [database connection]; setting a new progress handler cancels the 3268251883Speter** old one. ^Setting parameter X to NULL disables the progress handler. 3269251883Speter** ^The progress handler is also disabled by setting N to a value less 3270251883Speter** than 1. 3271251883Speter** 3272251883Speter** ^If the progress callback returns non-zero, the operation is 3273251883Speter** interrupted. This feature can be used to implement a 3274251883Speter** "Cancel" button on a GUI progress dialog box. 3275251883Speter** 3276251883Speter** The progress handler callback must not do anything that will modify 3277251883Speter** the database connection that invoked the progress handler. 3278251883Speter** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 3279251883Speter** database connections for the meaning of "modify" in this paragraph. 3280251883Speter** 3281251883Speter*/ 3282322444SpeterSQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); 3283251883Speter 3284251883Speter/* 3285251883Speter** CAPI3REF: Opening A New Database Connection 3286286510Speter** CONSTRUCTOR: sqlite3 3287251883Speter** 3288366076Scy** ^These routines open an SQLite database file as specified by the 3289251883Speter** filename argument. ^The filename argument is interpreted as UTF-8 for 3290251883Speter** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte 3291251883Speter** order for sqlite3_open16(). ^(A [database connection] handle is usually 3292251883Speter** returned in *ppDb, even if an error occurs. The only exception is that 3293251883Speter** if SQLite is unable to allocate memory to hold the [sqlite3] object, 3294251883Speter** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] 3295251883Speter** object.)^ ^(If the database is opened (and/or created) successfully, then 3296251883Speter** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The 3297251883Speter** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain 3298251883Speter** an English language description of the error following a failure of any 3299251883Speter** of the sqlite3_open() routines. 3300251883Speter** 3301274884Sbapt** ^The default encoding will be UTF-8 for databases created using 3302274884Sbapt** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases 3303274884Sbapt** created using sqlite3_open16() will be UTF-16 in the native byte order. 3304251883Speter** 3305251883Speter** Whether or not an error occurs when it is opened, resources 3306251883Speter** associated with the [database connection] handle should be released by 3307251883Speter** passing it to [sqlite3_close()] when it is no longer required. 3308251883Speter** 3309251883Speter** The sqlite3_open_v2() interface works like sqlite3_open() 3310251883Speter** except that it accepts two additional parameters for additional control 3311251883Speter** over the new database connection. ^(The flags parameter to 3312361456Scy** sqlite3_open_v2() must include, at a minimum, one of the following 3313361456Scy** three flag combinations:)^ 3314251883Speter** 3315251883Speter** <dl> 3316251883Speter** ^(<dt>[SQLITE_OPEN_READONLY]</dt> 3317251883Speter** <dd>The database is opened in read-only mode. If the database does not 3318251883Speter** already exist, an error is returned.</dd>)^ 3319251883Speter** 3320251883Speter** ^(<dt>[SQLITE_OPEN_READWRITE]</dt> 3321251883Speter** <dd>The database is opened for reading and writing if possible, or reading 3322251883Speter** only if the file is write protected by the operating system. In either 3323251883Speter** case the database must already exist, otherwise an error is returned.</dd>)^ 3324251883Speter** 3325251883Speter** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt> 3326251883Speter** <dd>The database is opened for reading and writing, and is created if 3327251883Speter** it does not already exist. This is the behavior that is always used for 3328251883Speter** sqlite3_open() and sqlite3_open16().</dd>)^ 3329251883Speter** </dl> 3330251883Speter** 3331361456Scy** In addition to the required flags, the following optional flags are 3332361456Scy** also supported: 3333361456Scy** 3334361456Scy** <dl> 3335361456Scy** ^(<dt>[SQLITE_OPEN_URI]</dt> 3336361456Scy** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^ 3337361456Scy** 3338361456Scy** ^(<dt>[SQLITE_OPEN_MEMORY]</dt> 3339361456Scy** <dd>The database will be opened as an in-memory database. The database 3340361456Scy** is named by the "filename" argument for the purposes of cache-sharing, 3341361456Scy** if shared cache mode is enabled, but the "filename" is otherwise ignored. 3342361456Scy** </dd>)^ 3343361456Scy** 3344361456Scy** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt> 3345361456Scy** <dd>The new database connection will use the "multi-thread" 3346361456Scy** [threading mode].)^ This means that separate threads are allowed 3347361456Scy** to use SQLite at the same time, as long as each thread is using 3348361456Scy** a different [database connection]. 3349361456Scy** 3350361456Scy** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt> 3351361456Scy** <dd>The new database connection will use the "serialized" 3352361456Scy** [threading mode].)^ This means the multiple threads can safely 3353361456Scy** attempt to use the same database connection at the same time. 3354361456Scy** (Mutexes will block any actual concurrency, but in this mode 3355361456Scy** there is no harm in trying.) 3356361456Scy** 3357361456Scy** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt> 3358361456Scy** <dd>The database is opened [shared cache] enabled, overriding 3359361456Scy** the default shared cache setting provided by 3360361456Scy** [sqlite3_enable_shared_cache()].)^ 3361361456Scy** 3362361456Scy** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt> 3363361456Scy** <dd>The database is opened [shared cache] disabled, overriding 3364361456Scy** the default shared cache setting provided by 3365361456Scy** [sqlite3_enable_shared_cache()].)^ 3366361456Scy** 3367361456Scy** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt> 3368361456Scy** <dd>The database filename is not allowed to be a symbolic link</dd> 3369361456Scy** </dl>)^ 3370361456Scy** 3371251883Speter** If the 3rd parameter to sqlite3_open_v2() is not one of the 3372361456Scy** required combinations shown above optionally combined with other 3373251883Speter** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits] 3374251883Speter** then the behavior is undefined. 3375251883Speter** 3376251883Speter** ^The fourth parameter to sqlite3_open_v2() is the name of the 3377251883Speter** [sqlite3_vfs] object that defines the operating system interface that 3378251883Speter** the new database connection should use. ^If the fourth parameter is 3379251883Speter** a NULL pointer then the default [sqlite3_vfs] object is used. 3380251883Speter** 3381251883Speter** ^If the filename is ":memory:", then a private, temporary in-memory database 3382251883Speter** is created for the connection. ^This in-memory database will vanish when 3383251883Speter** the database connection is closed. Future versions of SQLite might 3384251883Speter** make use of additional special filenames that begin with the ":" character. 3385251883Speter** It is recommended that when a database filename actually does begin with 3386251883Speter** a ":" character you should prefix the filename with a pathname such as 3387251883Speter** "./" to avoid ambiguity. 3388251883Speter** 3389251883Speter** ^If the filename is an empty string, then a private, temporary 3390251883Speter** on-disk database will be created. ^This private database will be 3391251883Speter** automatically deleted as soon as the database connection is closed. 3392251883Speter** 3393251883Speter** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3> 3394251883Speter** 3395251883Speter** ^If [URI filename] interpretation is enabled, and the filename argument 3396251883Speter** begins with "file:", then the filename is interpreted as a URI. ^URI 3397251883Speter** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is 3398342292Scy** set in the third argument to sqlite3_open_v2(), or if it has 3399251883Speter** been enabled globally using the [SQLITE_CONFIG_URI] option with the 3400251883Speter** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option. 3401342292Scy** URI filename interpretation is turned off 3402251883Speter** by default, but future releases of SQLite might enable URI filename 3403251883Speter** interpretation by default. See "[URI filenames]" for additional 3404251883Speter** information. 3405251883Speter** 3406251883Speter** URI filenames are parsed according to RFC 3986. ^If the URI contains an 3407366076Scy** authority, then it must be either an empty string or the string 3408366076Scy** "localhost". ^If the authority is not an empty string or "localhost", an 3409366076Scy** error is returned to the caller. ^The fragment component of a URI, if 3410251883Speter** present, is ignored. 3411251883Speter** 3412251883Speter** ^SQLite uses the path component of the URI as the name of the disk file 3413366076Scy** which contains the database. ^If the path begins with a '/' character, 3414366076Scy** then it is interpreted as an absolute path. ^If the path does not begin 3415251883Speter** with a '/' (meaning that the authority section is omitted from the URI) 3416366076Scy** then the path is interpreted as a relative path. 3417366076Scy** ^(On windows, the first component of an absolute path 3418274884Sbapt** is a drive specification (e.g. "C:").)^ 3419251883Speter** 3420251883Speter** [[core URI query parameters]] 3421251883Speter** The query component of a URI may contain parameters that are interpreted 3422251883Speter** either by SQLite itself, or by a [VFS | custom VFS implementation]. 3423274884Sbapt** SQLite and its built-in [VFSes] interpret the 3424274884Sbapt** following query parameters: 3425251883Speter** 3426251883Speter** <ul> 3427251883Speter** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of 3428251883Speter** a VFS object that provides the operating system interface that should 3429251883Speter** be used to access the database file on disk. ^If this option is set to 3430251883Speter** an empty string the default VFS object is used. ^Specifying an unknown 3431251883Speter** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is 3432251883Speter** present, then the VFS specified by the option takes precedence over 3433251883Speter** the value passed as the fourth parameter to sqlite3_open_v2(). 3434251883Speter** 3435251883Speter** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw", 3436251883Speter** "rwc", or "memory". Attempting to set it to any other value is 3437366076Scy** an error)^. 3438366076Scy** ^If "ro" is specified, then the database is opened for read-only 3439366076Scy** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the 3440366076Scy** third argument to sqlite3_open_v2(). ^If the mode option is set to 3441366076Scy** "rw", then the database is opened for read-write (but not create) 3442366076Scy** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had 3443366076Scy** been set. ^Value "rwc" is equivalent to setting both 3444251883Speter** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is 3445251883Speter** set to "memory" then a pure [in-memory database] that never reads 3446251883Speter** or writes from disk is used. ^It is an error to specify a value for 3447251883Speter** the mode parameter that is less restrictive than that specified by 3448251883Speter** the flags passed in the third parameter to sqlite3_open_v2(). 3449251883Speter** 3450251883Speter** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or 3451251883Speter** "private". ^Setting it to "shared" is equivalent to setting the 3452251883Speter** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to 3453366076Scy** sqlite3_open_v2(). ^Setting the cache parameter to "private" is 3454251883Speter** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit. 3455251883Speter** ^If sqlite3_open_v2() is used and the "cache" parameter is present in 3456251883Speter** a URI filename, its value overrides any behavior requested by setting 3457251883Speter** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag. 3458269851Speter** 3459274884Sbapt** <li> <b>psow</b>: ^The psow parameter indicates whether or not the 3460269851Speter** [powersafe overwrite] property does or does not apply to the 3461274884Sbapt** storage media on which the database file resides. 3462269851Speter** 3463269851Speter** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter 3464269851Speter** which if set disables file locking in rollback journal modes. This 3465269851Speter** is useful for accessing a database on a filesystem that does not 3466269851Speter** support locking. Caution: Database corruption might result if two 3467269851Speter** or more processes write to the same database and any one of those 3468269851Speter** processes uses nolock=1. 3469269851Speter** 3470269851Speter** <li> <b>immutable</b>: ^The immutable parameter is a boolean query 3471269851Speter** parameter that indicates that the database file is stored on 3472269851Speter** read-only media. ^When immutable is set, SQLite assumes that the 3473269851Speter** database file cannot be changed, even by a process with higher 3474269851Speter** privilege, and so the database is opened read-only and all locking 3475269851Speter** and change detection is disabled. Caution: Setting the immutable 3476269851Speter** property on a database file that does in fact change can result 3477269851Speter** in incorrect query results and/or [SQLITE_CORRUPT] errors. 3478269851Speter** See also: [SQLITE_IOCAP_IMMUTABLE]. 3479366076Scy** 3480251883Speter** </ul> 3481251883Speter** 3482251883Speter** ^Specifying an unknown parameter in the query component of a URI is not an 3483251883Speter** error. Future versions of SQLite might understand additional query 3484251883Speter** parameters. See "[query parameters with special meaning to SQLite]" for 3485251883Speter** additional information. 3486251883Speter** 3487251883Speter** [[URI filename examples]] <h3>URI filename examples</h3> 3488251883Speter** 3489251883Speter** <table border="1" align=center cellpadding=5> 3490251883Speter** <tr><th> URI filenames <th> Results 3491366076Scy** <tr><td> file:data.db <td> 3492251883Speter** Open the file "data.db" in the current directory. 3493251883Speter** <tr><td> file:/home/fred/data.db<br> 3494366076Scy** file:///home/fred/data.db <br> 3495366076Scy** file://localhost/home/fred/data.db <br> <td> 3496251883Speter** Open the database file "/home/fred/data.db". 3497366076Scy** <tr><td> file://darkstar/home/fred/data.db <td> 3498251883Speter** An error. "darkstar" is not a recognized authority. 3499366076Scy** <tr><td style="white-space:nowrap"> 3500251883Speter** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db 3501251883Speter** <td> Windows only: Open the file "data.db" on fred's desktop on drive 3502366076Scy** C:. Note that the %20 escaping in this example is not strictly 3503251883Speter** necessary - space characters can be used literally 3504251883Speter** in URI filenames. 3505366076Scy** <tr><td> file:data.db?mode=ro&cache=private <td> 3506251883Speter** Open file "data.db" in the current directory for read-only access. 3507251883Speter** Regardless of whether or not shared-cache mode is enabled by 3508251883Speter** default, use a private cache. 3509269851Speter** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td> 3510269851Speter** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile" 3511269851Speter** that uses dot-files in place of posix advisory locking. 3512366076Scy** <tr><td> file:data.db?mode=readonly <td> 3513251883Speter** An error. "readonly" is not a valid option for the "mode" parameter. 3514369951Scy** Use "ro" instead: "file:data.db?mode=ro". 3515251883Speter** </table> 3516251883Speter** 3517251883Speter** ^URI hexadecimal escape sequences (%HH) are supported within the path and 3518251883Speter** query components of a URI. A hexadecimal escape sequence consists of a 3519366076Scy** percent sign - "%" - followed by exactly two hexadecimal digits 3520251883Speter** specifying an octet value. ^Before the path or query components of a 3521366076Scy** URI filename are interpreted, they are encoded using UTF-8 and all 3522251883Speter** hexadecimal escape sequences replaced by a single byte containing the 3523251883Speter** corresponding octet. If this process generates an invalid UTF-8 encoding, 3524251883Speter** the results are undefined. 3525251883Speter** 3526251883Speter** <b>Note to Windows users:</b> The encoding used for the filename argument 3527251883Speter** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever 3528251883Speter** codepage is currently defined. Filenames containing international 3529251883Speter** characters must be converted to UTF-8 prior to passing them into 3530251883Speter** sqlite3_open() or sqlite3_open_v2(). 3531251883Speter** 3532251883Speter** <b>Note to Windows Runtime users:</b> The temporary directory must be set 3533251883Speter** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various 3534251883Speter** features that require the use of temporary files may fail. 3535251883Speter** 3536251883Speter** See also: [sqlite3_temp_directory] 3537251883Speter*/ 3538322444SpeterSQLITE_API int sqlite3_open( 3539251883Speter const char *filename, /* Database filename (UTF-8) */ 3540251883Speter sqlite3 **ppDb /* OUT: SQLite db handle */ 3541251883Speter); 3542322444SpeterSQLITE_API int sqlite3_open16( 3543251883Speter const void *filename, /* Database filename (UTF-16) */ 3544251883Speter sqlite3 **ppDb /* OUT: SQLite db handle */ 3545251883Speter); 3546322444SpeterSQLITE_API int sqlite3_open_v2( 3547251883Speter const char *filename, /* Database filename (UTF-8) */ 3548251883Speter sqlite3 **ppDb, /* OUT: SQLite db handle */ 3549251883Speter int flags, /* Flags */ 3550251883Speter const char *zVfs /* Name of VFS module to use */ 3551251883Speter); 3552251883Speter 3553251883Speter/* 3554251883Speter** CAPI3REF: Obtain Values For URI Parameters 3555251883Speter** 3556361456Scy** These are utility routines, useful to [VFS|custom VFS implementations], 3557366076Scy** that check if a database file was a URI that contained a specific query 3558251883Speter** parameter, and if so obtains the value of that query parameter. 3559251883Speter** 3560362190Scy** The first parameter to these interfaces (hereafter referred to 3561362190Scy** as F) must be one of: 3562362190Scy** <ul> 3563362190Scy** <li> A database filename pointer created by the SQLite core and 3564362190Scy** passed into the xOpen() method of a VFS implemention, or 3565362190Scy** <li> A filename obtained from [sqlite3_db_filename()], or 3566362190Scy** <li> A new filename constructed using [sqlite3_create_filename()]. 3567362190Scy** </ul> 3568362190Scy** If the F parameter is not one of the above, then the behavior is 3569362190Scy** undefined and probably undesirable. Older versions of SQLite were 3570362190Scy** more tolerant of invalid F parameters than newer versions. 3571362190Scy** 3572362190Scy** If F is a suitable filename (as described in the previous paragraph) 3573361456Scy** and if P is the name of the query parameter, then 3574251883Speter** sqlite3_uri_parameter(F,P) returns the value of the P 3575366076Scy** parameter if it exists or a NULL pointer if P does not appear as a 3576361456Scy** query parameter on F. If P is a query parameter of F and it 3577251883Speter** has no explicit value, then sqlite3_uri_parameter(F,P) returns 3578251883Speter** a pointer to an empty string. 3579251883Speter** 3580251883Speter** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean 3581251883Speter** parameter and returns true (1) or false (0) according to the value 3582251883Speter** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the 3583251883Speter** value of query parameter P is one of "yes", "true", or "on" in any 3584366076Scy** case or if the value begins with a non-zero number. The 3585251883Speter** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of 3586251883Speter** query parameter P is one of "no", "false", or "off" in any case or 3587251883Speter** if the value begins with a numeric zero. If P is not a query 3588361456Scy** parameter on F or if the value of P does not match any of the 3589251883Speter** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0). 3590251883Speter** 3591251883Speter** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a 3592251883Speter** 64-bit signed integer and returns that integer, or D if P does not 3593251883Speter** exist. If the value of P is something other than an integer, then 3594251883Speter** zero is returned. 3595361456Scy** 3596361456Scy** The sqlite3_uri_key(F,N) returns a pointer to the name (not 3597361456Scy** the value) of the N-th query parameter for filename F, or a NULL 3598361456Scy** pointer if N is less than zero or greater than the number of query 3599361456Scy** parameters minus 1. The N value is zero-based so N should be 0 to obtain 3600361456Scy** the name of the first query parameter, 1 for the second parameter, and 3601361456Scy** so forth. 3602366076Scy** 3603251883Speter** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and 3604251883Speter** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and 3605361456Scy** is not a database file pathname pointer that the SQLite core passed 3606361456Scy** into the xOpen VFS method, then the behavior of this routine is undefined 3607361456Scy** and probably undesirable. 3608346442Scy** 3609361456Scy** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F 3610361456Scy** parameter can also be the name of a rollback journal file or WAL file 3611361456Scy** in addition to the main database file. Prior to version 3.31.0, these 3612361456Scy** routines would only work if F was the name of the main database file. 3613361456Scy** When the F parameter is the name of the rollback journal or WAL file, 3614361456Scy** it has access to all the same query parameters as were found on the 3615361456Scy** main database file. 3616361456Scy** 3617346442Scy** See the [URI filename] documentation for additional information. 3618251883Speter*/ 3619322444SpeterSQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam); 3620322444SpeterSQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault); 3621322444SpeterSQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64); 3622361456ScySQLITE_API const char *sqlite3_uri_key(const char *zFilename, int N); 3623251883Speter 3624361456Scy/* 3625361456Scy** CAPI3REF: Translate filenames 3626361456Scy** 3627361456Scy** These routines are available to [VFS|custom VFS implementations] for 3628361456Scy** translating filenames between the main database file, the journal file, 3629361456Scy** and the WAL file. 3630361456Scy** 3631361456Scy** If F is the name of an sqlite database file, journal file, or WAL file 3632361456Scy** passed by the SQLite core into the VFS, then sqlite3_filename_database(F) 3633361456Scy** returns the name of the corresponding database file. 3634361456Scy** 3635361456Scy** If F is the name of an sqlite database file, journal file, or WAL file 3636361456Scy** passed by the SQLite core into the VFS, or if F is a database filename 3637361456Scy** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F) 3638361456Scy** returns the name of the corresponding rollback journal file. 3639361456Scy** 3640361456Scy** If F is the name of an sqlite database file, journal file, or WAL file 3641361456Scy** that was passed by the SQLite core into the VFS, or if F is a database 3642361456Scy** filename obtained from [sqlite3_db_filename()], then 3643361456Scy** sqlite3_filename_wal(F) returns the name of the corresponding 3644361456Scy** WAL file. 3645361456Scy** 3646361456Scy** In all of the above, if F is not the name of a database, journal or WAL 3647361456Scy** filename passed into the VFS from the SQLite core and F is not the 3648361456Scy** return value from [sqlite3_db_filename()], then the result is 3649361456Scy** undefined and is likely a memory access violation. 3650361456Scy*/ 3651361456ScySQLITE_API const char *sqlite3_filename_database(const char*); 3652361456ScySQLITE_API const char *sqlite3_filename_journal(const char*); 3653361456ScySQLITE_API const char *sqlite3_filename_wal(const char*); 3654251883Speter 3655362190Scy/* 3656362190Scy** CAPI3REF: Database File Corresponding To A Journal 3657362190Scy** 3658362190Scy** ^If X is the name of a rollback or WAL-mode journal file that is 3659366076Scy** passed into the xOpen method of [sqlite3_vfs], then 3660362190Scy** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file] 3661362190Scy** object that represents the main database file. 3662362190Scy** 3663362190Scy** This routine is intended for use in custom [VFS] implementations 3664362190Scy** only. It is not a general-purpose interface. 3665362190Scy** The argument sqlite3_file_object(X) must be a filename pointer that 3666366076Scy** has been passed into [sqlite3_vfs].xOpen method where the 3667362190Scy** flags parameter to xOpen contains one of the bits 3668362190Scy** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL]. Any other use 3669362190Scy** of this routine results in undefined and probably undesirable 3670362190Scy** behavior. 3671362190Scy*/ 3672362190ScySQLITE_API sqlite3_file *sqlite3_database_file_object(const char*); 3673361456Scy 3674251883Speter/* 3675362190Scy** CAPI3REF: Create and Destroy VFS Filenames 3676362190Scy** 3677362190Scy** These interfces are provided for use by [VFS shim] implementations and 3678362190Scy** are not useful outside of that context. 3679362190Scy** 3680362190Scy** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of 3681362190Scy** database filename D with corresponding journal file J and WAL file W and 3682362190Scy** with N URI parameters key/values pairs in the array P. The result from 3683362190Scy** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that 3684362190Scy** is safe to pass to routines like: 3685362190Scy** <ul> 3686362190Scy** <li> [sqlite3_uri_parameter()], 3687362190Scy** <li> [sqlite3_uri_boolean()], 3688362190Scy** <li> [sqlite3_uri_int64()], 3689366076Scy** <li> [sqlite3_uri_key()], 3690362190Scy** <li> [sqlite3_filename_database()], 3691362190Scy** <li> [sqlite3_filename_journal()], or 3692362190Scy** <li> [sqlite3_filename_wal()]. 3693362190Scy** </ul> 3694362190Scy** If a memory allocation error occurs, sqlite3_create_filename() might 3695362190Scy** return a NULL pointer. The memory obtained from sqlite3_create_filename(X) 3696362190Scy** must be released by a corresponding call to sqlite3_free_filename(Y). 3697362190Scy** 3698362190Scy** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array 3699362190Scy** of 2*N pointers to strings. Each pair of pointers in this array corresponds 3700362190Scy** to a key and value for a query parameter. The P parameter may be a NULL 3701362190Scy** pointer if N is zero. None of the 2*N pointers in the P array may be 3702362190Scy** NULL pointers and key pointers should not be empty strings. 3703362190Scy** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may 3704362190Scy** be NULL pointers, though they can be empty strings. 3705362190Scy** 3706362190Scy** The sqlite3_free_filename(Y) routine releases a memory allocation 3707362190Scy** previously obtained from sqlite3_create_filename(). Invoking 3708362190Scy** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op. 3709362190Scy** 3710362190Scy** If the Y parameter to sqlite3_free_filename(Y) is anything other 3711362190Scy** than a NULL pointer or a pointer previously acquired from 3712362190Scy** sqlite3_create_filename(), then bad things such as heap 3713369950Scy** corruption or segfaults may occur. The value Y should not be 3714362190Scy** used again after sqlite3_free_filename(Y) has been called. This means 3715362190Scy** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y, 3716362190Scy** then the corresponding [sqlite3_module.xClose() method should also be 3717362190Scy** invoked prior to calling sqlite3_free_filename(Y). 3718362190Scy*/ 3719362190ScySQLITE_API char *sqlite3_create_filename( 3720362190Scy const char *zDatabase, 3721362190Scy const char *zJournal, 3722362190Scy const char *zWal, 3723362190Scy int nParam, 3724362190Scy const char **azParam 3725362190Scy); 3726362190ScySQLITE_API void sqlite3_free_filename(char*); 3727362190Scy 3728362190Scy/* 3729251883Speter** CAPI3REF: Error Codes And Messages 3730286510Speter** METHOD: sqlite3 3731251883Speter** 3732366076Scy** ^If the most recent sqlite3_* API call associated with 3733282328Sbapt** [database connection] D failed, then the sqlite3_errcode(D) interface 3734282328Sbapt** returns the numeric [result code] or [extended result code] for that 3735282328Sbapt** API call. 3736282328Sbapt** ^The sqlite3_extended_errcode() 3737366076Scy** interface is the same except that it always returns the 3738251883Speter** [extended result code] even when extended result codes are 3739251883Speter** disabled. 3740251883Speter** 3741342292Scy** The values returned by sqlite3_errcode() and/or 3742342292Scy** sqlite3_extended_errcode() might change with each API call. 3743342292Scy** Except, there are some interfaces that are guaranteed to never 3744342292Scy** change the value of the error code. The error-code preserving 3745342292Scy** interfaces are: 3746342292Scy** 3747342292Scy** <ul> 3748342292Scy** <li> sqlite3_errcode() 3749342292Scy** <li> sqlite3_extended_errcode() 3750342292Scy** <li> sqlite3_errmsg() 3751342292Scy** <li> sqlite3_errmsg16() 3752342292Scy** </ul> 3753342292Scy** 3754251883Speter** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language 3755251883Speter** text that describes the error, as either UTF-8 or UTF-16 respectively. 3756251883Speter** ^(Memory to hold the error message string is managed internally. 3757251883Speter** The application does not need to worry about freeing the result. 3758251883Speter** However, the error string might be overwritten or deallocated by 3759251883Speter** subsequent calls to other SQLite interface functions.)^ 3760251883Speter** 3761251883Speter** ^The sqlite3_errstr() interface returns the English-language text 3762251883Speter** that describes the [result code], as UTF-8. 3763251883Speter** ^(Memory to hold the error message string is managed internally 3764251883Speter** and must not be freed by the application)^. 3765251883Speter** 3766251883Speter** When the serialized [threading mode] is in use, it might be the 3767251883Speter** case that a second error occurs on a separate thread in between 3768251883Speter** the time of the first error and the call to these interfaces. 3769251883Speter** When that happens, the second error will be reported since these 3770251883Speter** interfaces always report the most recent result. To avoid 3771251883Speter** this, each thread can obtain exclusive use of the [database connection] D 3772251883Speter** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning 3773251883Speter** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after 3774251883Speter** all calls to the interfaces listed here are completed. 3775251883Speter** 3776251883Speter** If an interface fails with SQLITE_MISUSE, that means the interface 3777251883Speter** was invoked incorrectly by the application. In that case, the 3778251883Speter** error code and message may or may not be set. 3779251883Speter*/ 3780322444SpeterSQLITE_API int sqlite3_errcode(sqlite3 *db); 3781322444SpeterSQLITE_API int sqlite3_extended_errcode(sqlite3 *db); 3782322444SpeterSQLITE_API const char *sqlite3_errmsg(sqlite3*); 3783322444SpeterSQLITE_API const void *sqlite3_errmsg16(sqlite3*); 3784322444SpeterSQLITE_API const char *sqlite3_errstr(int); 3785251883Speter 3786251883Speter/* 3787286510Speter** CAPI3REF: Prepared Statement Object 3788251883Speter** KEYWORDS: {prepared statement} {prepared statements} 3789251883Speter** 3790286510Speter** An instance of this object represents a single SQL statement that 3791286510Speter** has been compiled into binary form and is ready to be evaluated. 3792251883Speter** 3793286510Speter** Think of each SQL statement as a separate computer program. The 3794366076Scy** original SQL text is source code. A prepared statement object 3795286510Speter** is the compiled object code. All SQL must be converted into a 3796286510Speter** prepared statement before it can be run. 3797251883Speter** 3798286510Speter** The life-cycle of a prepared statement object usually goes like this: 3799286510Speter** 3800251883Speter** <ol> 3801286510Speter** <li> Create the prepared statement object using [sqlite3_prepare_v2()]. 3802286510Speter** <li> Bind values to [parameters] using the sqlite3_bind_*() 3803251883Speter** interfaces. 3804251883Speter** <li> Run the SQL by calling [sqlite3_step()] one or more times. 3805286510Speter** <li> Reset the prepared statement using [sqlite3_reset()] then go back 3806251883Speter** to step 2. Do this zero or more times. 3807251883Speter** <li> Destroy the object using [sqlite3_finalize()]. 3808251883Speter** </ol> 3809251883Speter*/ 3810251883Spetertypedef struct sqlite3_stmt sqlite3_stmt; 3811251883Speter 3812251883Speter/* 3813251883Speter** CAPI3REF: Run-time Limits 3814286510Speter** METHOD: sqlite3 3815251883Speter** 3816251883Speter** ^(This interface allows the size of various constructs to be limited 3817251883Speter** on a connection by connection basis. The first parameter is the 3818251883Speter** [database connection] whose limit is to be set or queried. The 3819251883Speter** second parameter is one of the [limit categories] that define a 3820251883Speter** class of constructs to be size limited. The third parameter is the 3821251883Speter** new limit for that construct.)^ 3822251883Speter** 3823251883Speter** ^If the new limit is a negative number, the limit is unchanged. 3824366076Scy** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a 3825251883Speter** [limits | hard upper bound] 3826251883Speter** set at compile-time by a C preprocessor macro called 3827251883Speter** [limits | SQLITE_MAX_<i>NAME</i>]. 3828251883Speter** (The "_LIMIT_" in the name is changed to "_MAX_".))^ 3829251883Speter** ^Attempts to increase a limit above its hard upper bound are 3830251883Speter** silently truncated to the hard upper bound. 3831251883Speter** 3832366076Scy** ^Regardless of whether or not the limit was changed, the 3833251883Speter** [sqlite3_limit()] interface returns the prior value of the limit. 3834251883Speter** ^Hence, to find the current value of a limit without changing it, 3835251883Speter** simply invoke this interface with the third parameter set to -1. 3836251883Speter** 3837251883Speter** Run-time limits are intended for use in applications that manage 3838251883Speter** both their own internal database and also databases that are controlled 3839251883Speter** by untrusted external sources. An example application might be a 3840251883Speter** web browser that has its own databases for storing history and 3841251883Speter** separate databases controlled by JavaScript applications downloaded 3842251883Speter** off the Internet. The internal databases can be given the 3843251883Speter** large, default limits. Databases managed by external sources can 3844251883Speter** be given much smaller limits designed to prevent a denial of service 3845251883Speter** attack. Developers might also want to use the [sqlite3_set_authorizer()] 3846251883Speter** interface to further control untrusted SQL. The size of the database 3847251883Speter** created by an untrusted script can be contained using the 3848251883Speter** [max_page_count] [PRAGMA]. 3849251883Speter** 3850251883Speter** New run-time limit categories may be added in future releases. 3851251883Speter*/ 3852322444SpeterSQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal); 3853251883Speter 3854251883Speter/* 3855251883Speter** CAPI3REF: Run-Time Limit Categories 3856251883Speter** KEYWORDS: {limit category} {*limit categories} 3857251883Speter** 3858251883Speter** These constants define various performance limits 3859251883Speter** that can be lowered at run-time using [sqlite3_limit()]. 3860251883Speter** The synopsis of the meanings of the various limits is shown below. 3861251883Speter** Additional information is available at [limits | Limits in SQLite]. 3862251883Speter** 3863251883Speter** <dl> 3864251883Speter** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt> 3865251883Speter** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^ 3866251883Speter** 3867251883Speter** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt> 3868251883Speter** <dd>The maximum length of an SQL statement, in bytes.</dd>)^ 3869251883Speter** 3870251883Speter** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt> 3871251883Speter** <dd>The maximum number of columns in a table definition or in the 3872251883Speter** result set of a [SELECT] or the maximum number of columns in an index 3873251883Speter** or in an ORDER BY or GROUP BY clause.</dd>)^ 3874251883Speter** 3875251883Speter** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt> 3876251883Speter** <dd>The maximum depth of the parse tree on any expression.</dd>)^ 3877251883Speter** 3878251883Speter** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt> 3879251883Speter** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^ 3880251883Speter** 3881251883Speter** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt> 3882251883Speter** <dd>The maximum number of instructions in a virtual machine program 3883322444Speter** used to implement an SQL statement. If [sqlite3_prepare_v2()] or 3884322444Speter** the equivalent tries to allocate space for more than this many opcodes 3885322444Speter** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^ 3886251883Speter** 3887251883Speter** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt> 3888251883Speter** <dd>The maximum number of arguments on a function.</dd>)^ 3889251883Speter** 3890251883Speter** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt> 3891251883Speter** <dd>The maximum number of [ATTACH | attached databases].)^</dd> 3892251883Speter** 3893251883Speter** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]] 3894251883Speter** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt> 3895251883Speter** <dd>The maximum length of the pattern argument to the [LIKE] or 3896251883Speter** [GLOB] operators.</dd>)^ 3897251883Speter** 3898251883Speter** [[SQLITE_LIMIT_VARIABLE_NUMBER]] 3899251883Speter** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt> 3900251883Speter** <dd>The maximum index number of any [parameter] in an SQL statement.)^ 3901251883Speter** 3902251883Speter** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt> 3903251883Speter** <dd>The maximum depth of recursion for triggers.</dd>)^ 3904274884Sbapt** 3905274884Sbapt** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt> 3906274884Sbapt** <dd>The maximum number of auxiliary worker threads that a single 3907274884Sbapt** [prepared statement] may start.</dd>)^ 3908251883Speter** </dl> 3909251883Speter*/ 3910251883Speter#define SQLITE_LIMIT_LENGTH 0 3911251883Speter#define SQLITE_LIMIT_SQL_LENGTH 1 3912251883Speter#define SQLITE_LIMIT_COLUMN 2 3913251883Speter#define SQLITE_LIMIT_EXPR_DEPTH 3 3914251883Speter#define SQLITE_LIMIT_COMPOUND_SELECT 4 3915251883Speter#define SQLITE_LIMIT_VDBE_OP 5 3916251883Speter#define SQLITE_LIMIT_FUNCTION_ARG 6 3917251883Speter#define SQLITE_LIMIT_ATTACHED 7 3918251883Speter#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 3919251883Speter#define SQLITE_LIMIT_VARIABLE_NUMBER 9 3920251883Speter#define SQLITE_LIMIT_TRIGGER_DEPTH 10 3921274884Sbapt#define SQLITE_LIMIT_WORKER_THREADS 11 3922251883Speter 3923251883Speter/* 3924322444Speter** CAPI3REF: Prepare Flags 3925322444Speter** 3926322444Speter** These constants define various flags that can be passed into 3927322444Speter** "prepFlags" parameter of the [sqlite3_prepare_v3()] and 3928322444Speter** [sqlite3_prepare16_v3()] interfaces. 3929322444Speter** 3930322444Speter** New flags may be added in future releases of SQLite. 3931322444Speter** 3932322444Speter** <dl> 3933322444Speter** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt> 3934322444Speter** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner 3935322444Speter** that the prepared statement will be retained for a long time and 3936322444Speter** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()] 3937366076Scy** and [sqlite3_prepare16_v3()] assume that the prepared statement will 3938322444Speter** be used just once or at most a few times and then destroyed using 3939322444Speter** [sqlite3_finalize()] relatively soon. The current implementation acts 3940322444Speter** on this hint by avoiding the use of [lookaside memory] so as not to 3941322444Speter** deplete the limited store of lookaside memory. Future versions of 3942322444Speter** SQLite may act on this hint differently. 3943342292Scy** 3944346442Scy** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt> 3945346442Scy** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used 3946346442Scy** to be required for any prepared statement that wanted to use the 3947346442Scy** [sqlite3_normalized_sql()] interface. However, the 3948346442Scy** [sqlite3_normalized_sql()] interface is now available to all 3949346442Scy** prepared statements, regardless of whether or not they use this 3950346442Scy** flag. 3951346442Scy** 3952346442Scy** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt> 3953346442Scy** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler 3954346442Scy** to return an error (error code SQLITE_ERROR) if the statement uses 3955346442Scy** any virtual tables. 3956322444Speter** </dl> 3957322444Speter*/ 3958322444Speter#define SQLITE_PREPARE_PERSISTENT 0x01 3959342292Scy#define SQLITE_PREPARE_NORMALIZE 0x02 3960346442Scy#define SQLITE_PREPARE_NO_VTAB 0x04 3961322444Speter 3962322444Speter/* 3963251883Speter** CAPI3REF: Compiling An SQL Statement 3964251883Speter** KEYWORDS: {SQL statement compiler} 3965286510Speter** METHOD: sqlite3 3966286510Speter** CONSTRUCTOR: sqlite3_stmt 3967251883Speter** 3968322444Speter** To execute an SQL statement, it must first be compiled into a byte-code 3969322444Speter** program using one of these routines. Or, in other words, these routines 3970322444Speter** are constructors for the [prepared statement] object. 3971251883Speter** 3972322444Speter** The preferred routine to use is [sqlite3_prepare_v2()]. The 3973322444Speter** [sqlite3_prepare()] interface is legacy and should be avoided. 3974322444Speter** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used 3975322444Speter** for special purposes. 3976322444Speter** 3977322444Speter** The use of the UTF-8 interfaces is preferred, as SQLite currently 3978322444Speter** does all parsing using UTF-8. The UTF-16 interfaces are provided 3979322444Speter** as a convenience. The UTF-16 interfaces work by converting the 3980322444Speter** input text into UTF-8, then invoking the corresponding UTF-8 interface. 3981322444Speter** 3982251883Speter** The first argument, "db", is a [database connection] obtained from a 3983251883Speter** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or 3984251883Speter** [sqlite3_open16()]. The database connection must not have been closed. 3985251883Speter** 3986251883Speter** The second argument, "zSql", is the statement to be compiled, encoded 3987322444Speter** as either UTF-8 or UTF-16. The sqlite3_prepare(), sqlite3_prepare_v2(), 3988322444Speter** and sqlite3_prepare_v3() 3989322444Speter** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(), 3990322444Speter** and sqlite3_prepare16_v3() use UTF-16. 3991251883Speter** 3992282328Sbapt** ^If the nByte argument is negative, then zSql is read up to the 3993282328Sbapt** first zero terminator. ^If nByte is positive, then it is the 3994282328Sbapt** number of bytes read from zSql. ^If nByte is zero, then no prepared 3995282328Sbapt** statement is generated. 3996282328Sbapt** If the caller knows that the supplied string is nul-terminated, then 3997282328Sbapt** there is a small performance advantage to passing an nByte parameter that 3998282328Sbapt** is the number of bytes in the input string <i>including</i> 3999282328Sbapt** the nul-terminator. 4000251883Speter** 4001251883Speter** ^If pzTail is not NULL then *pzTail is made to point to the first byte 4002251883Speter** past the end of the first SQL statement in zSql. These routines only 4003251883Speter** compile the first statement in zSql, so *pzTail is left pointing to 4004251883Speter** what remains uncompiled. 4005251883Speter** 4006251883Speter** ^*ppStmt is left pointing to a compiled [prepared statement] that can be 4007251883Speter** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set 4008251883Speter** to NULL. ^If the input text contains no SQL (if the input is an empty 4009251883Speter** string or a comment) then *ppStmt is set to NULL. 4010251883Speter** The calling procedure is responsible for deleting the compiled 4011251883Speter** SQL statement using [sqlite3_finalize()] after it has finished with it. 4012251883Speter** ppStmt may not be NULL. 4013251883Speter** 4014251883Speter** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK]; 4015251883Speter** otherwise an [error code] is returned. 4016251883Speter** 4017322444Speter** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(), 4018322444Speter** and sqlite3_prepare16_v3() interfaces are recommended for all new programs. 4019322444Speter** The older interfaces (sqlite3_prepare() and sqlite3_prepare16()) 4020322444Speter** are retained for backwards compatibility, but their use is discouraged. 4021322444Speter** ^In the "vX" interfaces, the prepared statement 4022251883Speter** that is returned (the [sqlite3_stmt] object) contains a copy of the 4023251883Speter** original SQL text. This causes the [sqlite3_step()] interface to 4024251883Speter** behave differently in three ways: 4025251883Speter** 4026251883Speter** <ol> 4027251883Speter** <li> 4028251883Speter** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it 4029251883Speter** always used to do, [sqlite3_step()] will automatically recompile the SQL 4030251883Speter** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY] 4031251883Speter** retries will occur before sqlite3_step() gives up and returns an error. 4032251883Speter** </li> 4033251883Speter** 4034251883Speter** <li> 4035251883Speter** ^When an error occurs, [sqlite3_step()] will return one of the detailed 4036251883Speter** [error codes] or [extended error codes]. ^The legacy behavior was that 4037251883Speter** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code 4038251883Speter** and the application would have to make a second call to [sqlite3_reset()] 4039251883Speter** in order to find the underlying cause of the problem. With the "v2" prepare 4040251883Speter** interfaces, the underlying reason for the error is returned immediately. 4041251883Speter** </li> 4042251883Speter** 4043251883Speter** <li> 4044366076Scy** ^If the specific value bound to a [parameter | host parameter] in the 4045251883Speter** WHERE clause might influence the choice of query plan for a statement, 4046366076Scy** then the statement will be automatically recompiled, as if there had been 4047361456Scy** a schema change, on the first [sqlite3_step()] call following any change 4048366076Scy** to the [sqlite3_bind_text | bindings] of that [parameter]. 4049366076Scy** ^The specific value of a WHERE-clause [parameter] might influence the 4050251883Speter** choice of query plan if the parameter is the left-hand side of a [LIKE] 4051251883Speter** or [GLOB] operator or if the parameter is compared to an indexed column 4052355326Scy** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled. 4053251883Speter** </li> 4054342292Scy** </ol> 4055322444Speter** 4056322444Speter** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having 4057322444Speter** the extra prepFlags parameter, which is a bit array consisting of zero or 4058322444Speter** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The 4059322444Speter** sqlite3_prepare_v2() interface works exactly the same as 4060322444Speter** sqlite3_prepare_v3() with a zero prepFlags parameter. 4061251883Speter*/ 4062322444SpeterSQLITE_API int sqlite3_prepare( 4063251883Speter sqlite3 *db, /* Database handle */ 4064251883Speter const char *zSql, /* SQL statement, UTF-8 encoded */ 4065251883Speter int nByte, /* Maximum length of zSql in bytes. */ 4066251883Speter sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4067251883Speter const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4068251883Speter); 4069322444SpeterSQLITE_API int sqlite3_prepare_v2( 4070251883Speter sqlite3 *db, /* Database handle */ 4071251883Speter const char *zSql, /* SQL statement, UTF-8 encoded */ 4072251883Speter int nByte, /* Maximum length of zSql in bytes. */ 4073251883Speter sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4074251883Speter const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4075251883Speter); 4076322444SpeterSQLITE_API int sqlite3_prepare_v3( 4077251883Speter sqlite3 *db, /* Database handle */ 4078322444Speter const char *zSql, /* SQL statement, UTF-8 encoded */ 4079322444Speter int nByte, /* Maximum length of zSql in bytes. */ 4080322444Speter unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ 4081322444Speter sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4082322444Speter const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4083322444Speter); 4084322444SpeterSQLITE_API int sqlite3_prepare16( 4085322444Speter sqlite3 *db, /* Database handle */ 4086251883Speter const void *zSql, /* SQL statement, UTF-16 encoded */ 4087251883Speter int nByte, /* Maximum length of zSql in bytes. */ 4088251883Speter sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4089251883Speter const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4090251883Speter); 4091322444SpeterSQLITE_API int sqlite3_prepare16_v2( 4092251883Speter sqlite3 *db, /* Database handle */ 4093251883Speter const void *zSql, /* SQL statement, UTF-16 encoded */ 4094251883Speter int nByte, /* Maximum length of zSql in bytes. */ 4095251883Speter sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4096251883Speter const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4097251883Speter); 4098322444SpeterSQLITE_API int sqlite3_prepare16_v3( 4099322444Speter sqlite3 *db, /* Database handle */ 4100322444Speter const void *zSql, /* SQL statement, UTF-16 encoded */ 4101322444Speter int nByte, /* Maximum length of zSql in bytes. */ 4102322444Speter unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ 4103322444Speter sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4104322444Speter const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4105322444Speter); 4106251883Speter 4107251883Speter/* 4108251883Speter** CAPI3REF: Retrieving Statement SQL 4109286510Speter** METHOD: sqlite3_stmt 4110251883Speter** 4111305002Scy** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8 4112305002Scy** SQL text used to create [prepared statement] P if P was 4113322444Speter** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], 4114322444Speter** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. 4115305002Scy** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8 4116305002Scy** string containing the SQL text of prepared statement P with 4117305002Scy** [bound parameters] expanded. 4118342292Scy** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8 4119342292Scy** string containing the normalized SQL text of prepared statement P. The 4120342292Scy** semantics used to normalize a SQL statement are unspecified and subject 4121342292Scy** to change. At a minimum, literal values will be replaced with suitable 4122342292Scy** placeholders. 4123305002Scy** 4124305002Scy** ^(For example, if a prepared statement is created using the SQL 4125305002Scy** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345 4126305002Scy** and parameter :xyz is unbound, then sqlite3_sql() will return 4127305002Scy** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql() 4128305002Scy** will return "SELECT 2345,NULL".)^ 4129305002Scy** 4130305002Scy** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory 4131305002Scy** is available to hold the result, or if the result would exceed the 4132305002Scy** the maximum string length determined by the [SQLITE_LIMIT_LENGTH]. 4133305002Scy** 4134305002Scy** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of 4135305002Scy** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time 4136305002Scy** option causes sqlite3_expanded_sql() to always return NULL. 4137305002Scy** 4138342292Scy** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P) 4139342292Scy** are managed by SQLite and are automatically freed when the prepared 4140342292Scy** statement is finalized. 4141305002Scy** ^The string returned by sqlite3_expanded_sql(P), on the other hand, 4142305002Scy** is obtained from [sqlite3_malloc()] and must be free by the application 4143305002Scy** by passing it to [sqlite3_free()]. 4144251883Speter*/ 4145322444SpeterSQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt); 4146322444SpeterSQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt); 4147342292ScySQLITE_API const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt); 4148251883Speter 4149251883Speter/* 4150251883Speter** CAPI3REF: Determine If An SQL Statement Writes The Database 4151286510Speter** METHOD: sqlite3_stmt 4152251883Speter** 4153251883Speter** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if 4154251883Speter** and only if the [prepared statement] X makes no direct changes to 4155251883Speter** the content of the database file. 4156251883Speter** 4157251883Speter** Note that [application-defined SQL functions] or 4158366076Scy** [virtual tables] might change the database indirectly as a side effect. 4159366076Scy** ^(For example, if an application defines a function "eval()" that 4160251883Speter** calls [sqlite3_exec()], then the following SQL statement would 4161251883Speter** change the database file through side-effects: 4162251883Speter** 4163251883Speter** <blockquote><pre> 4164251883Speter** SELECT eval('DELETE FROM t1') FROM t2; 4165251883Speter** </pre></blockquote> 4166251883Speter** 4167251883Speter** But because the [SELECT] statement does not change the database file 4168251883Speter** directly, sqlite3_stmt_readonly() would still return true.)^ 4169251883Speter** 4170251883Speter** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK], 4171251883Speter** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true, 4172251883Speter** since the statements themselves do not actually modify the database but 4173366076Scy** rather they control the timing of when other statements modify the 4174251883Speter** database. ^The [ATTACH] and [DETACH] statements also cause 4175251883Speter** sqlite3_stmt_readonly() to return true since, while those statements 4176366076Scy** change the configuration of a database connection, they do not make 4177251883Speter** changes to the content of the database files on disk. 4178322444Speter** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since 4179322444Speter** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and 4180322444Speter** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so 4181322444Speter** sqlite3_stmt_readonly() returns false for those commands. 4182251883Speter*/ 4183322444SpeterSQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt); 4184251883Speter 4185251883Speter/* 4186347347Scy** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement 4187347347Scy** METHOD: sqlite3_stmt 4188347347Scy** 4189347347Scy** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the 4190347347Scy** prepared statement S is an EXPLAIN statement, or 2 if the 4191347347Scy** statement S is an EXPLAIN QUERY PLAN. 4192347347Scy** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is 4193347347Scy** an ordinary statement or a NULL pointer. 4194347347Scy*/ 4195347347ScySQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt); 4196347347Scy 4197347347Scy/* 4198251883Speter** CAPI3REF: Determine If A Prepared Statement Has Been Reset 4199286510Speter** METHOD: sqlite3_stmt 4200251883Speter** 4201251883Speter** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the 4202366076Scy** [prepared statement] S has been stepped at least once using 4203298161Sbapt** [sqlite3_step(S)] but has neither run to completion (returned 4204298161Sbapt** [SQLITE_DONE] from [sqlite3_step(S)]) nor 4205251883Speter** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S) 4206366076Scy** interface returns false if S is a NULL pointer. If S is not a 4207251883Speter** NULL pointer and is not a pointer to a valid [prepared statement] 4208251883Speter** object, then the behavior is undefined and probably undesirable. 4209251883Speter** 4210251883Speter** This interface can be used in combination [sqlite3_next_stmt()] 4211366076Scy** to locate all prepared statements associated with a database 4212251883Speter** connection that are in need of being reset. This can be used, 4213366076Scy** for example, in diagnostic routines to search for prepared 4214251883Speter** statements that are holding a transaction open. 4215251883Speter*/ 4216322444SpeterSQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*); 4217251883Speter 4218251883Speter/* 4219251883Speter** CAPI3REF: Dynamically Typed Value Object 4220251883Speter** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} 4221251883Speter** 4222251883Speter** SQLite uses the sqlite3_value object to represent all values 4223251883Speter** that can be stored in a database table. SQLite uses dynamic typing 4224251883Speter** for the values it stores. ^Values stored in sqlite3_value objects 4225251883Speter** can be integers, floating point values, strings, BLOBs, or NULL. 4226251883Speter** 4227251883Speter** An sqlite3_value object may be either "protected" or "unprotected". 4228251883Speter** Some interfaces require a protected sqlite3_value. Other interfaces 4229251883Speter** will accept either a protected or an unprotected sqlite3_value. 4230251883Speter** Every interface that accepts sqlite3_value arguments specifies 4231286510Speter** whether or not it requires a protected sqlite3_value. The 4232366076Scy** [sqlite3_value_dup()] interface can be used to construct a new 4233286510Speter** protected sqlite3_value from an unprotected sqlite3_value. 4234251883Speter** 4235251883Speter** The terms "protected" and "unprotected" refer to whether or not 4236251883Speter** a mutex is held. An internal mutex is held for a protected 4237251883Speter** sqlite3_value object but no mutex is held for an unprotected 4238251883Speter** sqlite3_value object. If SQLite is compiled to be single-threaded 4239251883Speter** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) 4240366076Scy** or if SQLite is run in one of reduced mutex modes 4241251883Speter** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] 4242251883Speter** then there is no distinction between protected and unprotected 4243251883Speter** sqlite3_value objects and they can be used interchangeably. However, 4244251883Speter** for maximum code portability it is recommended that applications 4245251883Speter** still make the distinction between protected and unprotected 4246251883Speter** sqlite3_value objects even when not strictly required. 4247251883Speter** 4248251883Speter** ^The sqlite3_value objects that are passed as parameters into the 4249251883Speter** implementation of [application-defined SQL functions] are protected. 4250251883Speter** ^The sqlite3_value object returned by 4251251883Speter** [sqlite3_column_value()] is unprotected. 4252342292Scy** Unprotected sqlite3_value objects may only be used as arguments 4253342292Scy** to [sqlite3_result_value()], [sqlite3_bind_value()], and 4254342292Scy** [sqlite3_value_dup()]. 4255251883Speter** The [sqlite3_value_blob | sqlite3_value_type()] family of 4256251883Speter** interfaces require protected sqlite3_value objects. 4257251883Speter*/ 4258322444Spetertypedef struct sqlite3_value sqlite3_value; 4259251883Speter 4260251883Speter/* 4261251883Speter** CAPI3REF: SQL Function Context Object 4262251883Speter** 4263251883Speter** The context in which an SQL function executes is stored in an 4264251883Speter** sqlite3_context object. ^A pointer to an sqlite3_context object 4265251883Speter** is always first parameter to [application-defined SQL functions]. 4266251883Speter** The application-defined SQL function implementation will pass this 4267251883Speter** pointer through into calls to [sqlite3_result_int | sqlite3_result()], 4268251883Speter** [sqlite3_aggregate_context()], [sqlite3_user_data()], 4269251883Speter** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], 4270251883Speter** and/or [sqlite3_set_auxdata()]. 4271251883Speter*/ 4272251883Spetertypedef struct sqlite3_context sqlite3_context; 4273251883Speter 4274251883Speter/* 4275251883Speter** CAPI3REF: Binding Values To Prepared Statements 4276251883Speter** KEYWORDS: {host parameter} {host parameters} {host parameter name} 4277251883Speter** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} 4278286510Speter** METHOD: sqlite3_stmt 4279251883Speter** 4280251883Speter** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants, 4281251883Speter** literals may be replaced by a [parameter] that matches one of following 4282251883Speter** templates: 4283251883Speter** 4284251883Speter** <ul> 4285251883Speter** <li> ? 4286251883Speter** <li> ?NNN 4287251883Speter** <li> :VVV 4288251883Speter** <li> @VVV 4289251883Speter** <li> $VVV 4290251883Speter** </ul> 4291251883Speter** 4292251883Speter** In the templates above, NNN represents an integer literal, 4293251883Speter** and VVV represents an alphanumeric identifier.)^ ^The values of these 4294251883Speter** parameters (also called "host parameter names" or "SQL parameters") 4295251883Speter** can be set using the sqlite3_bind_*() routines defined here. 4296251883Speter** 4297251883Speter** ^The first argument to the sqlite3_bind_*() routines is always 4298251883Speter** a pointer to the [sqlite3_stmt] object returned from 4299251883Speter** [sqlite3_prepare_v2()] or its variants. 4300251883Speter** 4301251883Speter** ^The second argument is the index of the SQL parameter to be set. 4302251883Speter** ^The leftmost SQL parameter has an index of 1. ^When the same named 4303251883Speter** SQL parameter is used more than once, second and subsequent 4304251883Speter** occurrences have the same index as the first occurrence. 4305251883Speter** ^The index for named parameters can be looked up using the 4306251883Speter** [sqlite3_bind_parameter_index()] API if desired. ^The index 4307251883Speter** for "?NNN" parameters is the value of NNN. 4308251883Speter** ^The NNN value must be between 1 and the [sqlite3_limit()] 4309362190Scy** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766). 4310251883Speter** 4311251883Speter** ^The third argument is the value to bind to the parameter. 4312251883Speter** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16() 4313251883Speter** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter 4314251883Speter** is ignored and the end result is the same as sqlite3_bind_null(). 4315362190Scy** ^If the third parameter to sqlite3_bind_text() is not NULL, then 4316362190Scy** it should be a pointer to well-formed UTF8 text. 4317362190Scy** ^If the third parameter to sqlite3_bind_text16() is not NULL, then 4318362190Scy** it should be a pointer to well-formed UTF16 text. 4319362190Scy** ^If the third parameter to sqlite3_bind_text64() is not NULL, then 4320362190Scy** it should be a pointer to a well-formed unicode string that is 4321362190Scy** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16 4322362190Scy** otherwise. 4323251883Speter** 4324362190Scy** [[byte-order determination rules]] ^The byte-order of 4325362190Scy** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF) 4326362190Scy** found in first character, which is removed, or in the absence of a BOM 4327362190Scy** the byte order is the native byte order of the host 4328362190Scy** machine for sqlite3_bind_text16() or the byte order specified in 4329366076Scy** the 6th parameter for sqlite3_bind_text64().)^ 4330362190Scy** ^If UTF16 input text contains invalid unicode 4331362190Scy** characters, then SQLite might change those invalid characters 4332362190Scy** into the unicode replacement character: U+FFFD. 4333362190Scy** 4334251883Speter** ^(In those routines that have a fourth argument, its value is the 4335251883Speter** number of bytes in the parameter. To be clear: the value is the 4336251883Speter** number of <u>bytes</u> in the value, not the number of characters.)^ 4337251883Speter** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16() 4338251883Speter** is negative, then the length of the string is 4339251883Speter** the number of bytes up to the first zero terminator. 4340251883Speter** If the fourth parameter to sqlite3_bind_blob() is negative, then 4341251883Speter** the behavior is undefined. 4342251883Speter** If a non-negative fourth parameter is provided to sqlite3_bind_text() 4343274884Sbapt** or sqlite3_bind_text16() or sqlite3_bind_text64() then 4344274884Sbapt** that parameter must be the byte offset 4345251883Speter** where the NUL terminator would occur assuming the string were NUL 4346366076Scy** terminated. If any NUL characters occurs at byte offsets less than 4347251883Speter** the value of the fourth parameter then the resulting string value will 4348251883Speter** contain embedded NULs. The result of expressions involving strings 4349251883Speter** with embedded NULs is undefined. 4350251883Speter** 4351274884Sbapt** ^The fifth argument to the BLOB and string binding interfaces 4352274884Sbapt** is a destructor used to dispose of the BLOB or 4353251883Speter** string after SQLite has finished with it. ^The destructor is called 4354347347Scy** to dispose of the BLOB or string even if the call to the bind API fails, 4355347347Scy** except the destructor is not called if the third parameter is a NULL 4356347347Scy** pointer or the fourth parameter is negative. 4357251883Speter** ^If the fifth argument is 4358251883Speter** the special value [SQLITE_STATIC], then SQLite assumes that the 4359251883Speter** information is in static, unmanaged space and does not need to be freed. 4360251883Speter** ^If the fifth argument has the value [SQLITE_TRANSIENT], then 4361251883Speter** SQLite makes its own private copy of the data immediately, before 4362251883Speter** the sqlite3_bind_*() routine returns. 4363251883Speter** 4364274884Sbapt** ^The sixth argument to sqlite3_bind_text64() must be one of 4365274884Sbapt** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE] 4366274884Sbapt** to specify the encoding of the text in the third parameter. If 4367274884Sbapt** the sixth argument to sqlite3_bind_text64() is not one of the 4368274884Sbapt** allowed values shown above, or if the text encoding is different 4369274884Sbapt** from the encoding specified by the sixth parameter, then the behavior 4370274884Sbapt** is undefined. 4371274884Sbapt** 4372251883Speter** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that 4373251883Speter** is filled with zeroes. ^A zeroblob uses a fixed amount of memory 4374251883Speter** (just an integer to hold its size) while it is being processed. 4375251883Speter** Zeroblobs are intended to serve as placeholders for BLOBs whose 4376251883Speter** content is later written using 4377251883Speter** [sqlite3_blob_open | incremental BLOB I/O] routines. 4378251883Speter** ^A negative value for the zeroblob results in a zero-length BLOB. 4379251883Speter** 4380322444Speter** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in 4381322444Speter** [prepared statement] S to have an SQL value of NULL, but to also be 4382322444Speter** associated with the pointer P of type T. ^D is either a NULL pointer or 4383322444Speter** a pointer to a destructor function for P. ^SQLite will invoke the 4384322444Speter** destructor D with a single argument of P when it is finished using 4385322444Speter** P. The T parameter should be a static string, preferably a string 4386322444Speter** literal. The sqlite3_bind_pointer() routine is part of the 4387322444Speter** [pointer passing interface] added for SQLite 3.20.0. 4388322444Speter** 4389251883Speter** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer 4390251883Speter** for the [prepared statement] or with a prepared statement for which 4391251883Speter** [sqlite3_step()] has been called more recently than [sqlite3_reset()], 4392251883Speter** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_() 4393251883Speter** routine is passed a [prepared statement] that has been finalized, the 4394251883Speter** result is undefined and probably harmful. 4395251883Speter** 4396251883Speter** ^Bindings are not cleared by the [sqlite3_reset()] routine. 4397251883Speter** ^Unbound parameters are interpreted as NULL. 4398251883Speter** 4399251883Speter** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an 4400251883Speter** [error code] if anything goes wrong. 4401274884Sbapt** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB 4402274884Sbapt** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or 4403274884Sbapt** [SQLITE_MAX_LENGTH]. 4404251883Speter** ^[SQLITE_RANGE] is returned if the parameter 4405251883Speter** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails. 4406251883Speter** 4407251883Speter** See also: [sqlite3_bind_parameter_count()], 4408251883Speter** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. 4409251883Speter*/ 4410322444SpeterSQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); 4411322444SpeterSQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64, 4412274884Sbapt void(*)(void*)); 4413322444SpeterSQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double); 4414322444SpeterSQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int); 4415322444SpeterSQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); 4416322444SpeterSQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int); 4417322444SpeterSQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*)); 4418322444SpeterSQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); 4419322444SpeterSQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64, 4420274884Sbapt void(*)(void*), unsigned char encoding); 4421322444SpeterSQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); 4422322444SpeterSQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*)); 4423322444SpeterSQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); 4424322444SpeterSQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64); 4425251883Speter 4426251883Speter/* 4427251883Speter** CAPI3REF: Number Of SQL Parameters 4428286510Speter** METHOD: sqlite3_stmt 4429251883Speter** 4430251883Speter** ^This routine can be used to find the number of [SQL parameters] 4431251883Speter** in a [prepared statement]. SQL parameters are tokens of the 4432251883Speter** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as 4433251883Speter** placeholders for values that are [sqlite3_bind_blob | bound] 4434251883Speter** to the parameters at a later time. 4435251883Speter** 4436251883Speter** ^(This routine actually returns the index of the largest (rightmost) 4437251883Speter** parameter. For all forms except ?NNN, this will correspond to the 4438251883Speter** number of unique parameters. If parameters of the ?NNN form are used, 4439251883Speter** there may be gaps in the list.)^ 4440251883Speter** 4441251883Speter** See also: [sqlite3_bind_blob|sqlite3_bind()], 4442251883Speter** [sqlite3_bind_parameter_name()], and 4443251883Speter** [sqlite3_bind_parameter_index()]. 4444251883Speter*/ 4445322444SpeterSQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*); 4446251883Speter 4447251883Speter/* 4448251883Speter** CAPI3REF: Name Of A Host Parameter 4449286510Speter** METHOD: sqlite3_stmt 4450251883Speter** 4451251883Speter** ^The sqlite3_bind_parameter_name(P,N) interface returns 4452251883Speter** the name of the N-th [SQL parameter] in the [prepared statement] P. 4453251883Speter** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" 4454251883Speter** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" 4455251883Speter** respectively. 4456251883Speter** In other words, the initial ":" or "$" or "@" or "?" 4457251883Speter** is included as part of the name.)^ 4458251883Speter** ^Parameters of the form "?" without a following integer have no name 4459251883Speter** and are referred to as "nameless" or "anonymous parameters". 4460251883Speter** 4461251883Speter** ^The first host parameter has an index of 1, not 0. 4462251883Speter** 4463251883Speter** ^If the value N is out of range or if the N-th parameter is 4464251883Speter** nameless, then NULL is returned. ^The returned string is 4465251883Speter** always in UTF-8 encoding even if the named parameter was 4466322444Speter** originally specified as UTF-16 in [sqlite3_prepare16()], 4467322444Speter** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. 4468251883Speter** 4469251883Speter** See also: [sqlite3_bind_blob|sqlite3_bind()], 4470251883Speter** [sqlite3_bind_parameter_count()], and 4471251883Speter** [sqlite3_bind_parameter_index()]. 4472251883Speter*/ 4473322444SpeterSQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); 4474251883Speter 4475251883Speter/* 4476251883Speter** CAPI3REF: Index Of A Parameter With A Given Name 4477286510Speter** METHOD: sqlite3_stmt 4478251883Speter** 4479251883Speter** ^Return the index of an SQL parameter given its name. ^The 4480251883Speter** index value returned is suitable for use as the second 4481251883Speter** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero 4482251883Speter** is returned if no matching parameter is found. ^The parameter 4483251883Speter** name must be given in UTF-8 even if the original statement 4484322444Speter** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or 4485322444Speter** [sqlite3_prepare16_v3()]. 4486251883Speter** 4487251883Speter** See also: [sqlite3_bind_blob|sqlite3_bind()], 4488251883Speter** [sqlite3_bind_parameter_count()], and 4489298161Sbapt** [sqlite3_bind_parameter_name()]. 4490251883Speter*/ 4491322444SpeterSQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); 4492251883Speter 4493251883Speter/* 4494251883Speter** CAPI3REF: Reset All Bindings On A Prepared Statement 4495286510Speter** METHOD: sqlite3_stmt 4496251883Speter** 4497251883Speter** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset 4498251883Speter** the [sqlite3_bind_blob | bindings] on a [prepared statement]. 4499251883Speter** ^Use this routine to reset all host parameters to NULL. 4500251883Speter*/ 4501322444SpeterSQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*); 4502251883Speter 4503251883Speter/* 4504251883Speter** CAPI3REF: Number Of Columns In A Result Set 4505286510Speter** METHOD: sqlite3_stmt 4506251883Speter** 4507251883Speter** ^Return the number of columns in the result set returned by the 4508366076Scy** [prepared statement]. ^If this routine returns 0, that means the 4509322444Speter** [prepared statement] returns no data (for example an [UPDATE]). 4510322444Speter** ^However, just because this routine returns a positive number does not 4511322444Speter** mean that one or more rows of data will be returned. ^A SELECT statement 4512322444Speter** will always have a positive sqlite3_column_count() but depending on the 4513322444Speter** WHERE clause constraints and the table content, it might return no rows. 4514251883Speter** 4515251883Speter** See also: [sqlite3_data_count()] 4516251883Speter*/ 4517322444SpeterSQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt); 4518251883Speter 4519251883Speter/* 4520251883Speter** CAPI3REF: Column Names In A Result Set 4521286510Speter** METHOD: sqlite3_stmt 4522251883Speter** 4523251883Speter** ^These routines return the name assigned to a particular column 4524251883Speter** in the result set of a [SELECT] statement. ^The sqlite3_column_name() 4525251883Speter** interface returns a pointer to a zero-terminated UTF-8 string 4526251883Speter** and sqlite3_column_name16() returns a pointer to a zero-terminated 4527251883Speter** UTF-16 string. ^The first parameter is the [prepared statement] 4528251883Speter** that implements the [SELECT] statement. ^The second parameter is the 4529251883Speter** column number. ^The leftmost column is number 0. 4530251883Speter** 4531251883Speter** ^The returned string pointer is valid until either the [prepared statement] 4532251883Speter** is destroyed by [sqlite3_finalize()] or until the statement is automatically 4533251883Speter** reprepared by the first call to [sqlite3_step()] for a particular run 4534251883Speter** or until the next call to 4535251883Speter** sqlite3_column_name() or sqlite3_column_name16() on the same column. 4536251883Speter** 4537251883Speter** ^If sqlite3_malloc() fails during the processing of either routine 4538251883Speter** (for example during a conversion from UTF-8 to UTF-16) then a 4539251883Speter** NULL pointer is returned. 4540251883Speter** 4541251883Speter** ^The name of a result column is the value of the "AS" clause for 4542251883Speter** that column, if there is an AS clause. If there is no AS clause 4543251883Speter** then the name of the column is unspecified and may change from 4544251883Speter** one release of SQLite to the next. 4545251883Speter*/ 4546322444SpeterSQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N); 4547322444SpeterSQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N); 4548251883Speter 4549251883Speter/* 4550251883Speter** CAPI3REF: Source Of Data In A Query Result 4551286510Speter** METHOD: sqlite3_stmt 4552251883Speter** 4553251883Speter** ^These routines provide a means to determine the database, table, and 4554251883Speter** table column that is the origin of a particular result column in 4555251883Speter** [SELECT] statement. 4556251883Speter** ^The name of the database or table or column can be returned as 4557251883Speter** either a UTF-8 or UTF-16 string. ^The _database_ routines return 4558251883Speter** the database name, the _table_ routines return the table name, and 4559251883Speter** the origin_ routines return the column name. 4560251883Speter** ^The returned string is valid until the [prepared statement] is destroyed 4561251883Speter** using [sqlite3_finalize()] or until the statement is automatically 4562251883Speter** reprepared by the first call to [sqlite3_step()] for a particular run 4563251883Speter** or until the same information is requested 4564251883Speter** again in a different encoding. 4565251883Speter** 4566251883Speter** ^The names returned are the original un-aliased names of the 4567251883Speter** database, table, and column. 4568251883Speter** 4569251883Speter** ^The first argument to these interfaces is a [prepared statement]. 4570251883Speter** ^These functions return information about the Nth result column returned by 4571251883Speter** the statement, where N is the second function argument. 4572251883Speter** ^The left-most column is column 0 for these routines. 4573251883Speter** 4574251883Speter** ^If the Nth column returned by the statement is an expression or 4575251883Speter** subquery and is not a column value, then all of these functions return 4576361456Scy** NULL. ^These routines might also return NULL if a memory allocation error 4577251883Speter** occurs. ^Otherwise, they return the name of the attached database, table, 4578251883Speter** or column that query result column was extracted from. 4579251883Speter** 4580251883Speter** ^As with all other SQLite APIs, those whose names end with "16" return 4581251883Speter** UTF-16 encoded strings and the other functions return UTF-8. 4582251883Speter** 4583251883Speter** ^These APIs are only available if the library was compiled with the 4584251883Speter** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol. 4585251883Speter** 4586251883Speter** If two or more threads call one or more 4587251883Speter** [sqlite3_column_database_name | column metadata interfaces] 4588251883Speter** for the same [prepared statement] and result column 4589251883Speter** at the same time then the results are undefined. 4590251883Speter*/ 4591322444SpeterSQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int); 4592322444SpeterSQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int); 4593322444SpeterSQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int); 4594322444SpeterSQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int); 4595322444SpeterSQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int); 4596322444SpeterSQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); 4597251883Speter 4598251883Speter/* 4599251883Speter** CAPI3REF: Declared Datatype Of A Query Result 4600286510Speter** METHOD: sqlite3_stmt 4601251883Speter** 4602251883Speter** ^(The first parameter is a [prepared statement]. 4603251883Speter** If this statement is a [SELECT] statement and the Nth column of the 4604251883Speter** returned result set of that [SELECT] is a table column (not an 4605251883Speter** expression or subquery) then the declared type of the table 4606251883Speter** column is returned.)^ ^If the Nth column of the result set is an 4607251883Speter** expression or subquery, then a NULL pointer is returned. 4608251883Speter** ^The returned string is always UTF-8 encoded. 4609251883Speter** 4610251883Speter** ^(For example, given the database schema: 4611251883Speter** 4612251883Speter** CREATE TABLE t1(c1 VARIANT); 4613251883Speter** 4614251883Speter** and the following statement to be compiled: 4615251883Speter** 4616251883Speter** SELECT c1 + 1, c1 FROM t1; 4617251883Speter** 4618251883Speter** this routine would return the string "VARIANT" for the second result 4619251883Speter** column (i==1), and a NULL pointer for the first result column (i==0).)^ 4620251883Speter** 4621251883Speter** ^SQLite uses dynamic run-time typing. ^So just because a column 4622251883Speter** is declared to contain a particular type does not mean that the 4623251883Speter** data stored in that column is of the declared type. SQLite is 4624251883Speter** strongly typed, but the typing is dynamic not static. ^Type 4625251883Speter** is associated with individual values, not with the containers 4626251883Speter** used to hold those values. 4627251883Speter*/ 4628322444SpeterSQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int); 4629322444SpeterSQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int); 4630251883Speter 4631251883Speter/* 4632251883Speter** CAPI3REF: Evaluate An SQL Statement 4633286510Speter** METHOD: sqlite3_stmt 4634251883Speter** 4635322444Speter** After a [prepared statement] has been prepared using any of 4636322444Speter** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()], 4637322444Speter** or [sqlite3_prepare16_v3()] or one of the legacy 4638251883Speter** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function 4639251883Speter** must be called one or more times to evaluate the statement. 4640251883Speter** 4641251883Speter** The details of the behavior of the sqlite3_step() interface depend 4642322444Speter** on whether the statement was prepared using the newer "vX" interfaces 4643322444Speter** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()], 4644322444Speter** [sqlite3_prepare16_v2()] or the older legacy 4645322444Speter** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the 4646322444Speter** new "vX" interface is recommended for new applications but the legacy 4647251883Speter** interface will continue to be supported. 4648251883Speter** 4649251883Speter** ^In the legacy interface, the return value will be either [SQLITE_BUSY], 4650251883Speter** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. 4651251883Speter** ^With the "v2" interface, any of the other [result codes] or 4652251883Speter** [extended result codes] might be returned as well. 4653251883Speter** 4654251883Speter** ^[SQLITE_BUSY] means that the database engine was unable to acquire the 4655251883Speter** database locks it needs to do its job. ^If the statement is a [COMMIT] 4656251883Speter** or occurs outside of an explicit transaction, then you can retry the 4657251883Speter** statement. If the statement is not a [COMMIT] and occurs within an 4658251883Speter** explicit transaction then you should rollback the transaction before 4659251883Speter** continuing. 4660251883Speter** 4661251883Speter** ^[SQLITE_DONE] means that the statement has finished executing 4662251883Speter** successfully. sqlite3_step() should not be called again on this virtual 4663251883Speter** machine without first calling [sqlite3_reset()] to reset the virtual 4664251883Speter** machine back to its initial state. 4665251883Speter** 4666251883Speter** ^If the SQL statement being executed returns any data, then [SQLITE_ROW] 4667251883Speter** is returned each time a new row of data is ready for processing by the 4668251883Speter** caller. The values may be accessed using the [column access functions]. 4669251883Speter** sqlite3_step() is called again to retrieve the next row of data. 4670251883Speter** 4671251883Speter** ^[SQLITE_ERROR] means that a run-time error (such as a constraint 4672251883Speter** violation) has occurred. sqlite3_step() should not be called again on 4673251883Speter** the VM. More information may be found by calling [sqlite3_errmsg()]. 4674251883Speter** ^With the legacy interface, a more specific error code (for example, 4675251883Speter** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) 4676251883Speter** can be obtained by calling [sqlite3_reset()] on the 4677251883Speter** [prepared statement]. ^In the "v2" interface, 4678251883Speter** the more specific error code is returned directly by sqlite3_step(). 4679251883Speter** 4680251883Speter** [SQLITE_MISUSE] means that the this routine was called inappropriately. 4681251883Speter** Perhaps it was called on a [prepared statement] that has 4682251883Speter** already been [sqlite3_finalize | finalized] or on one that had 4683251883Speter** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could 4684251883Speter** be the case that the same database connection is being used by two or 4685251883Speter** more threads at the same moment in time. 4686251883Speter** 4687251883Speter** For all versions of SQLite up to and including 3.6.23.1, a call to 4688251883Speter** [sqlite3_reset()] was required after sqlite3_step() returned anything 4689251883Speter** other than [SQLITE_ROW] before any subsequent invocation of 4690366076Scy** sqlite3_step(). Failure to reset the prepared statement using 4691251883Speter** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from 4692342292Scy** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1], 4693322444Speter** sqlite3_step() began 4694251883Speter** calling [sqlite3_reset()] automatically in this circumstance rather 4695251883Speter** than returning [SQLITE_MISUSE]. This is not considered a compatibility 4696251883Speter** break because any application that ever receives an SQLITE_MISUSE error 4697251883Speter** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option 4698251883Speter** can be used to restore the legacy behavior. 4699251883Speter** 4700251883Speter** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step() 4701251883Speter** API always returns a generic error code, [SQLITE_ERROR], following any 4702251883Speter** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call 4703251883Speter** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the 4704251883Speter** specific [error codes] that better describes the error. 4705251883Speter** We admit that this is a goofy design. The problem has been fixed 4706251883Speter** with the "v2" interface. If you prepare all of your SQL statements 4707322444Speter** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()] 4708322444Speter** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead 4709251883Speter** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, 4710251883Speter** then the more specific [error codes] are returned directly 4711322444Speter** by sqlite3_step(). The use of the "vX" interfaces is recommended. 4712251883Speter*/ 4713322444SpeterSQLITE_API int sqlite3_step(sqlite3_stmt*); 4714251883Speter 4715251883Speter/* 4716251883Speter** CAPI3REF: Number of columns in a result set 4717286510Speter** METHOD: sqlite3_stmt 4718251883Speter** 4719251883Speter** ^The sqlite3_data_count(P) interface returns the number of columns in the 4720251883Speter** current row of the result set of [prepared statement] P. 4721251883Speter** ^If prepared statement P does not have results ready to return 4722361456Scy** (via calls to the [sqlite3_column_int | sqlite3_column()] family of 4723251883Speter** interfaces) then sqlite3_data_count(P) returns 0. 4724251883Speter** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer. 4725251883Speter** ^The sqlite3_data_count(P) routine returns 0 if the previous call to 4726251883Speter** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P) 4727251883Speter** will return non-zero if previous call to [sqlite3_step](P) returned 4728251883Speter** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum] 4729251883Speter** where it always returns zero since each step of that multi-step 4730251883Speter** pragma returns 0 columns of data. 4731251883Speter** 4732251883Speter** See also: [sqlite3_column_count()] 4733251883Speter*/ 4734322444SpeterSQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt); 4735251883Speter 4736251883Speter/* 4737251883Speter** CAPI3REF: Fundamental Datatypes 4738251883Speter** KEYWORDS: SQLITE_TEXT 4739251883Speter** 4740251883Speter** ^(Every value in SQLite has one of five fundamental datatypes: 4741251883Speter** 4742251883Speter** <ul> 4743251883Speter** <li> 64-bit signed integer 4744251883Speter** <li> 64-bit IEEE floating point number 4745251883Speter** <li> string 4746251883Speter** <li> BLOB 4747251883Speter** <li> NULL 4748251883Speter** </ul>)^ 4749251883Speter** 4750251883Speter** These constants are codes for each of those types. 4751251883Speter** 4752251883Speter** Note that the SQLITE_TEXT constant was also used in SQLite version 2 4753251883Speter** for a completely different meaning. Software that links against both 4754251883Speter** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not 4755251883Speter** SQLITE_TEXT. 4756251883Speter*/ 4757251883Speter#define SQLITE_INTEGER 1 4758251883Speter#define SQLITE_FLOAT 2 4759251883Speter#define SQLITE_BLOB 4 4760251883Speter#define SQLITE_NULL 5 4761251883Speter#ifdef SQLITE_TEXT 4762251883Speter# undef SQLITE_TEXT 4763251883Speter#else 4764251883Speter# define SQLITE_TEXT 3 4765251883Speter#endif 4766251883Speter#define SQLITE3_TEXT 3 4767251883Speter 4768251883Speter/* 4769251883Speter** CAPI3REF: Result Values From A Query 4770251883Speter** KEYWORDS: {column access functions} 4771286510Speter** METHOD: sqlite3_stmt 4772251883Speter** 4773322444Speter** <b>Summary:</b> 4774322444Speter** <blockquote><table border=0 cellpadding=0 cellspacing=0> 4775322444Speter** <tr><td><b>sqlite3_column_blob</b><td>→<td>BLOB result 4776322444Speter** <tr><td><b>sqlite3_column_double</b><td>→<td>REAL result 4777322444Speter** <tr><td><b>sqlite3_column_int</b><td>→<td>32-bit INTEGER result 4778322444Speter** <tr><td><b>sqlite3_column_int64</b><td>→<td>64-bit INTEGER result 4779322444Speter** <tr><td><b>sqlite3_column_text</b><td>→<td>UTF-8 TEXT result 4780322444Speter** <tr><td><b>sqlite3_column_text16</b><td>→<td>UTF-16 TEXT result 4781366076Scy** <tr><td><b>sqlite3_column_value</b><td>→<td>The result as an 4782322444Speter** [sqlite3_value|unprotected sqlite3_value] object. 4783322444Speter** <tr><td> <td> <td> 4784322444Speter** <tr><td><b>sqlite3_column_bytes</b><td>→<td>Size of a BLOB 4785322444Speter** or a UTF-8 TEXT result in bytes 4786322444Speter** <tr><td><b>sqlite3_column_bytes16 </b> 4787322444Speter** <td>→ <td>Size of UTF-16 4788322444Speter** TEXT in bytes 4789322444Speter** <tr><td><b>sqlite3_column_type</b><td>→<td>Default 4790322444Speter** datatype of the result 4791322444Speter** </table></blockquote> 4792322444Speter** 4793322444Speter** <b>Details:</b> 4794322444Speter** 4795251883Speter** ^These routines return information about a single column of the current 4796251883Speter** result row of a query. ^In every case the first argument is a pointer 4797251883Speter** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] 4798251883Speter** that was returned from [sqlite3_prepare_v2()] or one of its variants) 4799251883Speter** and the second argument is the index of the column for which information 4800251883Speter** should be returned. ^The leftmost column of the result set has the index 0. 4801251883Speter** ^The number of columns in the result can be determined using 4802251883Speter** [sqlite3_column_count()]. 4803251883Speter** 4804251883Speter** If the SQL statement does not currently point to a valid row, or if the 4805251883Speter** column index is out of range, the result is undefined. 4806251883Speter** These routines may only be called when the most recent call to 4807251883Speter** [sqlite3_step()] has returned [SQLITE_ROW] and neither 4808251883Speter** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. 4809251883Speter** If any of these routines are called after [sqlite3_reset()] or 4810251883Speter** [sqlite3_finalize()] or after [sqlite3_step()] has returned 4811251883Speter** something other than [SQLITE_ROW], the results are undefined. 4812251883Speter** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] 4813251883Speter** are called from a different thread while any of these routines 4814251883Speter** are pending, then the results are undefined. 4815251883Speter** 4816322444Speter** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16) 4817322444Speter** each return the value of a result column in a specific data format. If 4818322444Speter** the result column is not initially in the requested format (for example, 4819322444Speter** if the query returns an integer but the sqlite3_column_text() interface 4820322444Speter** is used to extract the value) then an automatic type conversion is performed. 4821322444Speter** 4822251883Speter** ^The sqlite3_column_type() routine returns the 4823251883Speter** [SQLITE_INTEGER | datatype code] for the initial data type 4824251883Speter** of the result column. ^The returned value is one of [SQLITE_INTEGER], 4825322444Speter** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. 4826322444Speter** The return value of sqlite3_column_type() can be used to decide which 4827322444Speter** of the first six interface should be used to extract the column value. 4828322444Speter** The value returned by sqlite3_column_type() is only meaningful if no 4829366076Scy** automatic type conversions have occurred for the value in question. 4830322444Speter** After a type conversion, the result of calling sqlite3_column_type() 4831322444Speter** is undefined, though harmless. Future 4832251883Speter** versions of SQLite may change the behavior of sqlite3_column_type() 4833251883Speter** following a type conversion. 4834251883Speter** 4835322444Speter** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes() 4836322444Speter** or sqlite3_column_bytes16() interfaces can be used to determine the size 4837322444Speter** of that BLOB or string. 4838322444Speter** 4839251883Speter** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() 4840251883Speter** routine returns the number of bytes in that BLOB or string. 4841251883Speter** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts 4842251883Speter** the string to UTF-8 and then returns the number of bytes. 4843251883Speter** ^If the result is a numeric value then sqlite3_column_bytes() uses 4844251883Speter** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns 4845251883Speter** the number of bytes in that string. 4846251883Speter** ^If the result is NULL, then sqlite3_column_bytes() returns zero. 4847251883Speter** 4848251883Speter** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16() 4849251883Speter** routine returns the number of bytes in that BLOB or string. 4850251883Speter** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts 4851251883Speter** the string to UTF-16 and then returns the number of bytes. 4852251883Speter** ^If the result is a numeric value then sqlite3_column_bytes16() uses 4853251883Speter** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns 4854251883Speter** the number of bytes in that string. 4855251883Speter** ^If the result is NULL, then sqlite3_column_bytes16() returns zero. 4856251883Speter** 4857366076Scy** ^The values returned by [sqlite3_column_bytes()] and 4858251883Speter** [sqlite3_column_bytes16()] do not include the zero terminators at the end 4859251883Speter** of the string. ^For clarity: the values returned by 4860251883Speter** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of 4861251883Speter** bytes in the string, not the number of characters. 4862251883Speter** 4863251883Speter** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(), 4864251883Speter** even empty strings, are always zero-terminated. ^The return 4865251883Speter** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer. 4866251883Speter** 4867286510Speter** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an 4868286510Speter** [unprotected sqlite3_value] object. In a multithreaded environment, 4869286510Speter** an unprotected sqlite3_value object may only be used safely with 4870286510Speter** [sqlite3_bind_value()] and [sqlite3_result_value()]. 4871251883Speter** If the [unprotected sqlite3_value] object returned by 4872251883Speter** [sqlite3_column_value()] is used in any other way, including calls 4873251883Speter** to routines like [sqlite3_value_int()], [sqlite3_value_text()], 4874286510Speter** or [sqlite3_value_bytes()], the behavior is not threadsafe. 4875322444Speter** Hence, the sqlite3_column_value() interface 4876366076Scy** is normally only useful within the implementation of 4877322444Speter** [application-defined SQL functions] or [virtual tables], not within 4878322444Speter** top-level application code. 4879251883Speter** 4880322444Speter** The these routines may attempt to convert the datatype of the result. 4881322444Speter** ^For example, if the internal representation is FLOAT and a text result 4882251883Speter** is requested, [sqlite3_snprintf()] is used internally to perform the 4883251883Speter** conversion automatically. ^(The following table details the conversions 4884251883Speter** that are applied: 4885251883Speter** 4886251883Speter** <blockquote> 4887251883Speter** <table border="1"> 4888251883Speter** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion 4889251883Speter** 4890251883Speter** <tr><td> NULL <td> INTEGER <td> Result is 0 4891251883Speter** <tr><td> NULL <td> FLOAT <td> Result is 0.0 4892269851Speter** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer 4893269851Speter** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer 4894251883Speter** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float 4895251883Speter** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer 4896251883Speter** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT 4897269851Speter** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER 4898251883Speter** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float 4899269851Speter** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB 4900269851Speter** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER 4901269851Speter** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL 4902251883Speter** <tr><td> TEXT <td> BLOB <td> No change 4903269851Speter** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER 4904269851Speter** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL 4905251883Speter** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed 4906251883Speter** </table> 4907251883Speter** </blockquote>)^ 4908251883Speter** 4909251883Speter** Note that when type conversions occur, pointers returned by prior 4910251883Speter** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or 4911251883Speter** sqlite3_column_text16() may be invalidated. 4912251883Speter** Type conversions and pointer invalidations might occur 4913251883Speter** in the following cases: 4914251883Speter** 4915251883Speter** <ul> 4916251883Speter** <li> The initial content is a BLOB and sqlite3_column_text() or 4917251883Speter** sqlite3_column_text16() is called. A zero-terminator might 4918251883Speter** need to be added to the string.</li> 4919251883Speter** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or 4920251883Speter** sqlite3_column_text16() is called. The content must be converted 4921251883Speter** to UTF-16.</li> 4922251883Speter** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or 4923251883Speter** sqlite3_column_text() is called. The content must be converted 4924251883Speter** to UTF-8.</li> 4925251883Speter** </ul> 4926251883Speter** 4927251883Speter** ^Conversions between UTF-16be and UTF-16le are always done in place and do 4928251883Speter** not invalidate a prior pointer, though of course the content of the buffer 4929251883Speter** that the prior pointer references will have been modified. Other kinds 4930251883Speter** of conversion are done in place when it is possible, but sometimes they 4931251883Speter** are not possible and in those cases prior pointers are invalidated. 4932251883Speter** 4933286510Speter** The safest policy is to invoke these routines 4934251883Speter** in one of the following ways: 4935251883Speter** 4936251883Speter** <ul> 4937251883Speter** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li> 4938251883Speter** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li> 4939251883Speter** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li> 4940251883Speter** </ul> 4941251883Speter** 4942251883Speter** In other words, you should call sqlite3_column_text(), 4943251883Speter** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result 4944251883Speter** into the desired format, then invoke sqlite3_column_bytes() or 4945251883Speter** sqlite3_column_bytes16() to find the size of the result. Do not mix calls 4946251883Speter** to sqlite3_column_text() or sqlite3_column_blob() with calls to 4947251883Speter** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() 4948251883Speter** with calls to sqlite3_column_bytes(). 4949251883Speter** 4950251883Speter** ^The pointers returned are valid until a type conversion occurs as 4951251883Speter** described above, or until [sqlite3_step()] or [sqlite3_reset()] or 4952251883Speter** [sqlite3_finalize()] is called. ^The memory space used to hold strings 4953322444Speter** and BLOBs is freed automatically. Do not pass the pointers returned 4954269851Speter** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into 4955251883Speter** [sqlite3_free()]. 4956251883Speter** 4957342292Scy** As long as the input parameters are correct, these routines will only 4958342292Scy** fail if an out-of-memory error occurs during a format conversion. 4959342292Scy** Only the following subset of interfaces are subject to out-of-memory 4960342292Scy** errors: 4961342292Scy** 4962342292Scy** <ul> 4963342292Scy** <li> sqlite3_column_blob() 4964342292Scy** <li> sqlite3_column_text() 4965342292Scy** <li> sqlite3_column_text16() 4966342292Scy** <li> sqlite3_column_bytes() 4967342292Scy** <li> sqlite3_column_bytes16() 4968342292Scy** </ul> 4969342292Scy** 4970342292Scy** If an out-of-memory error occurs, then the return value from these 4971342292Scy** routines is the same as if the column had contained an SQL NULL value. 4972342292Scy** Valid SQL NULL returns can be distinguished from out-of-memory errors 4973342292Scy** by invoking the [sqlite3_errcode()] immediately after the suspect 4974342292Scy** return value is obtained and before any 4975342292Scy** other SQLite interface is called on the same [database connection]. 4976251883Speter*/ 4977322444SpeterSQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); 4978322444SpeterSQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol); 4979322444SpeterSQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol); 4980322444SpeterSQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); 4981322444SpeterSQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); 4982322444SpeterSQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); 4983322444SpeterSQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); 4984322444SpeterSQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol); 4985322444SpeterSQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); 4986322444SpeterSQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol); 4987251883Speter 4988251883Speter/* 4989251883Speter** CAPI3REF: Destroy A Prepared Statement Object 4990286510Speter** DESTRUCTOR: sqlite3_stmt 4991251883Speter** 4992251883Speter** ^The sqlite3_finalize() function is called to delete a [prepared statement]. 4993251883Speter** ^If the most recent evaluation of the statement encountered no errors 4994251883Speter** or if the statement is never been evaluated, then sqlite3_finalize() returns 4995251883Speter** SQLITE_OK. ^If the most recent evaluation of statement S failed, then 4996251883Speter** sqlite3_finalize(S) returns the appropriate [error code] or 4997251883Speter** [extended error code]. 4998251883Speter** 4999251883Speter** ^The sqlite3_finalize(S) routine can be called at any point during 5000251883Speter** the life cycle of [prepared statement] S: 5001251883Speter** before statement S is ever evaluated, after 5002251883Speter** one or more calls to [sqlite3_reset()], or after any call 5003251883Speter** to [sqlite3_step()] regardless of whether or not the statement has 5004251883Speter** completed execution. 5005251883Speter** 5006251883Speter** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op. 5007251883Speter** 5008251883Speter** The application must finalize every [prepared statement] in order to avoid 5009251883Speter** resource leaks. It is a grievous error for the application to try to use 5010251883Speter** a prepared statement after it has been finalized. Any use of a prepared 5011251883Speter** statement after it has been finalized can result in undefined and 5012251883Speter** undesirable behavior such as segfaults and heap corruption. 5013251883Speter*/ 5014322444SpeterSQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt); 5015251883Speter 5016251883Speter/* 5017251883Speter** CAPI3REF: Reset A Prepared Statement Object 5018286510Speter** METHOD: sqlite3_stmt 5019251883Speter** 5020251883Speter** The sqlite3_reset() function is called to reset a [prepared statement] 5021251883Speter** object back to its initial state, ready to be re-executed. 5022251883Speter** ^Any SQL statement variables that had values bound to them using 5023251883Speter** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. 5024251883Speter** Use [sqlite3_clear_bindings()] to reset the bindings. 5025251883Speter** 5026251883Speter** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S 5027251883Speter** back to the beginning of its program. 5028251883Speter** 5029251883Speter** ^If the most recent call to [sqlite3_step(S)] for the 5030251883Speter** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE], 5031251883Speter** or if [sqlite3_step(S)] has never before been called on S, 5032251883Speter** then [sqlite3_reset(S)] returns [SQLITE_OK]. 5033251883Speter** 5034251883Speter** ^If the most recent call to [sqlite3_step(S)] for the 5035251883Speter** [prepared statement] S indicated an error, then 5036251883Speter** [sqlite3_reset(S)] returns an appropriate [error code]. 5037251883Speter** 5038251883Speter** ^The [sqlite3_reset(S)] interface does not change the values 5039251883Speter** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. 5040251883Speter*/ 5041322444SpeterSQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt); 5042251883Speter 5043251883Speter/* 5044251883Speter** CAPI3REF: Create Or Redefine SQL Functions 5045251883Speter** KEYWORDS: {function creation routines} 5046286510Speter** METHOD: sqlite3 5047251883Speter** 5048251883Speter** ^These functions (collectively known as "function creation routines") 5049251883Speter** are used to add SQL functions or aggregates or to redefine the behavior 5050342292Scy** of existing SQL functions or aggregates. The only differences between 5051366076Scy** the three "sqlite3_create_function*" routines are the text encoding 5052366076Scy** expected for the second parameter (the name of the function being 5053342292Scy** created) and the presence or absence of a destructor callback for 5054342292Scy** the application data pointer. Function sqlite3_create_window_function() 5055342292Scy** is similar, but allows the user to supply the extra callback functions 5056342292Scy** needed by [aggregate window functions]. 5057251883Speter** 5058251883Speter** ^The first parameter is the [database connection] to which the SQL 5059251883Speter** function is to be added. ^If an application uses more than one database 5060251883Speter** connection then application-defined SQL functions must be added 5061251883Speter** to each database connection separately. 5062251883Speter** 5063251883Speter** ^The second parameter is the name of the SQL function to be created or 5064251883Speter** redefined. ^The length of the name is limited to 255 bytes in a UTF-8 5065251883Speter** representation, exclusive of the zero-terminator. ^Note that the name 5066366076Scy** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes. 5067251883Speter** ^Any attempt to create a function with a longer name 5068251883Speter** will result in [SQLITE_MISUSE] being returned. 5069251883Speter** 5070251883Speter** ^The third parameter (nArg) 5071251883Speter** is the number of arguments that the SQL function or 5072251883Speter** aggregate takes. ^If this parameter is -1, then the SQL function or 5073251883Speter** aggregate may take any number of arguments between 0 and the limit 5074251883Speter** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third 5075251883Speter** parameter is less than -1 or greater than 127 then the behavior is 5076251883Speter** undefined. 5077251883Speter** 5078251883Speter** ^The fourth parameter, eTextRep, specifies what 5079251883Speter** [SQLITE_UTF8 | text encoding] this SQL function prefers for 5080269851Speter** its parameters. The application should set this parameter to 5081366076Scy** [SQLITE_UTF16LE] if the function implementation invokes 5082269851Speter** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the 5083269851Speter** implementation invokes [sqlite3_value_text16be()] on an input, or 5084269851Speter** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8] 5085269851Speter** otherwise. ^The same SQL function may be registered multiple times using 5086269851Speter** different preferred text encodings, with different implementations for 5087269851Speter** each encoding. 5088251883Speter** ^When multiple implementations of the same function are available, SQLite 5089251883Speter** will pick the one that involves the least amount of data conversion. 5090251883Speter** 5091269851Speter** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC] 5092269851Speter** to signal that the function will always return the same result given 5093269851Speter** the same inputs within a single SQL statement. Most SQL functions are 5094269851Speter** deterministic. The built-in [random()] SQL function is an example of a 5095269851Speter** function that is not deterministic. The SQLite query planner is able to 5096269851Speter** perform additional optimizations on deterministic functions, so use 5097269851Speter** of the [SQLITE_DETERMINISTIC] flag is recommended where possible. 5098269851Speter** 5099355326Scy** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY] 5100355326Scy** flag, which if present prevents the function from being invoked from 5101361456Scy** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions, 5102361456Scy** index expressions, or the WHERE clause of partial indexes. 5103355326Scy** 5104361456Scy** <span style="background-color:#ffff90;"> 5105361456Scy** For best security, the [SQLITE_DIRECTONLY] flag is recommended for 5106361456Scy** all application-defined SQL functions that do not need to be 5107361456Scy** used inside of triggers, view, CHECK constraints, or other elements of 5108366076Scy** the database schema. This flags is especially recommended for SQL 5109361456Scy** functions that have side effects or reveal internal application state. 5110361456Scy** Without this flag, an attacker might be able to modify the schema of 5111361456Scy** a database file to include invocations of the function with parameters 5112361456Scy** chosen by the attacker, which the application will then execute when 5113361456Scy** the database file is opened and read. 5114361456Scy** </span> 5115361456Scy** 5116251883Speter** ^(The fifth parameter is an arbitrary pointer. The implementation of the 5117251883Speter** function can gain access to this pointer using [sqlite3_user_data()].)^ 5118251883Speter** 5119342292Scy** ^The sixth, seventh and eighth parameters passed to the three 5120342292Scy** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are 5121251883Speter** pointers to C-language functions that implement the SQL function or 5122251883Speter** aggregate. ^A scalar SQL function requires an implementation of the xFunc 5123251883Speter** callback only; NULL pointers must be passed as the xStep and xFinal 5124251883Speter** parameters. ^An aggregate SQL function requires an implementation of xStep 5125251883Speter** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing 5126251883Speter** SQL function or aggregate, pass NULL pointers for all three function 5127251883Speter** callbacks. 5128251883Speter** 5129366076Scy** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue 5130342292Scy** and xInverse) passed to sqlite3_create_window_function are pointers to 5131342292Scy** C-language callbacks that implement the new function. xStep and xFinal 5132342292Scy** must both be non-NULL. xValue and xInverse may either both be NULL, in 5133366076Scy** which case a regular aggregate function is created, or must both be 5134342292Scy** non-NULL, in which case the new function may be used as either an aggregate 5135342292Scy** or aggregate window function. More details regarding the implementation 5136366076Scy** of aggregate window functions are 5137342292Scy** [user-defined window functions|available here]. 5138251883Speter** 5139342292Scy** ^(If the final parameter to sqlite3_create_function_v2() or 5140342292Scy** sqlite3_create_window_function() is not NULL, then it is destructor for 5141366076Scy** the application data pointer. The destructor is invoked when the function 5142366076Scy** is deleted, either by being overloaded or when the database connection 5143366076Scy** closes.)^ ^The destructor is also invoked if the call to 5144342292Scy** sqlite3_create_function_v2() fails. ^When the destructor callback is 5145342292Scy** invoked, it is passed a single argument which is a copy of the application 5146342292Scy** data pointer which was the fifth parameter to sqlite3_create_function_v2(). 5147342292Scy** 5148251883Speter** ^It is permitted to register multiple implementations of the same 5149251883Speter** functions with the same name but with either differing numbers of 5150251883Speter** arguments or differing preferred text encodings. ^SQLite will use 5151251883Speter** the implementation that most closely matches the way in which the 5152251883Speter** SQL function is used. ^A function implementation with a non-negative 5153251883Speter** nArg parameter is a better match than a function implementation with 5154251883Speter** a negative nArg. ^A function where the preferred text encoding 5155251883Speter** matches the database encoding is a better 5156366076Scy** match than a function where the encoding is different. 5157251883Speter** ^A function where the encoding difference is between UTF16le and UTF16be 5158251883Speter** is a closer match than a function where the encoding difference is 5159251883Speter** between UTF8 and UTF16. 5160251883Speter** 5161251883Speter** ^Built-in functions may be overloaded by new application-defined functions. 5162251883Speter** 5163251883Speter** ^An application-defined function is permitted to call other 5164251883Speter** SQLite interfaces. However, such calls must not 5165251883Speter** close the database connection nor finalize or reset the prepared 5166251883Speter** statement in which the function is running. 5167251883Speter*/ 5168322444SpeterSQLITE_API int sqlite3_create_function( 5169251883Speter sqlite3 *db, 5170251883Speter const char *zFunctionName, 5171251883Speter int nArg, 5172251883Speter int eTextRep, 5173251883Speter void *pApp, 5174251883Speter void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5175251883Speter void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5176251883Speter void (*xFinal)(sqlite3_context*) 5177251883Speter); 5178322444SpeterSQLITE_API int sqlite3_create_function16( 5179251883Speter sqlite3 *db, 5180251883Speter const void *zFunctionName, 5181251883Speter int nArg, 5182251883Speter int eTextRep, 5183251883Speter void *pApp, 5184251883Speter void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5185251883Speter void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5186251883Speter void (*xFinal)(sqlite3_context*) 5187251883Speter); 5188322444SpeterSQLITE_API int sqlite3_create_function_v2( 5189251883Speter sqlite3 *db, 5190251883Speter const char *zFunctionName, 5191251883Speter int nArg, 5192251883Speter int eTextRep, 5193251883Speter void *pApp, 5194251883Speter void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5195251883Speter void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5196251883Speter void (*xFinal)(sqlite3_context*), 5197251883Speter void(*xDestroy)(void*) 5198251883Speter); 5199342292ScySQLITE_API int sqlite3_create_window_function( 5200342292Scy sqlite3 *db, 5201342292Scy const char *zFunctionName, 5202342292Scy int nArg, 5203342292Scy int eTextRep, 5204342292Scy void *pApp, 5205342292Scy void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5206342292Scy void (*xFinal)(sqlite3_context*), 5207342292Scy void (*xValue)(sqlite3_context*), 5208342292Scy void (*xInverse)(sqlite3_context*,int,sqlite3_value**), 5209342292Scy void(*xDestroy)(void*) 5210342292Scy); 5211251883Speter 5212251883Speter/* 5213251883Speter** CAPI3REF: Text Encodings 5214251883Speter** 5215251883Speter** These constant define integer codes that represent the various 5216251883Speter** text encodings supported by SQLite. 5217251883Speter*/ 5218282328Sbapt#define SQLITE_UTF8 1 /* IMP: R-37514-35566 */ 5219282328Sbapt#define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */ 5220282328Sbapt#define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */ 5221251883Speter#define SQLITE_UTF16 4 /* Use native byte order */ 5222269851Speter#define SQLITE_ANY 5 /* Deprecated */ 5223251883Speter#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ 5224251883Speter 5225251883Speter/* 5226269851Speter** CAPI3REF: Function Flags 5227269851Speter** 5228366076Scy** These constants may be ORed together with the 5229269851Speter** [SQLITE_UTF8 | preferred text encoding] as the fourth argument 5230269851Speter** to [sqlite3_create_function()], [sqlite3_create_function16()], or 5231269851Speter** [sqlite3_create_function_v2()]. 5232355326Scy** 5233361456Scy** <dl> 5234361456Scy** [[SQLITE_DETERMINISTIC]] <dt>SQLITE_DETERMINISTIC</dt><dd> 5235361456Scy** The SQLITE_DETERMINISTIC flag means that the new function always gives 5236361456Scy** the same output when the input parameters are the same. 5237361456Scy** The [abs|abs() function] is deterministic, for example, but 5238361456Scy** [randomblob|randomblob()] is not. Functions must 5239361456Scy** be deterministic in order to be used in certain contexts such as 5240361456Scy** with the WHERE clause of [partial indexes] or in [generated columns]. 5241361456Scy** SQLite might also optimize deterministic functions by factoring them 5242361456Scy** out of inner loops. 5243361456Scy** </dd> 5244366076Scy** 5245361456Scy** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd> 5246355326Scy** The SQLITE_DIRECTONLY flag means that the function may only be invoked 5247366076Scy** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in 5248361456Scy** schema structures such as [CHECK constraints], [DEFAULT clauses], 5249361456Scy** [expression indexes], [partial indexes], or [generated columns]. 5250361456Scy** The SQLITE_DIRECTONLY flags is a security feature which is recommended 5251361456Scy** for all [application-defined SQL functions], and especially for functions 5252361456Scy** that have side-effects or that could potentially leak sensitive 5253361456Scy** information. 5254361456Scy** </dd> 5255355326Scy** 5256361456Scy** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd> 5257361456Scy** The SQLITE_INNOCUOUS flag means that the function is unlikely 5258361456Scy** to cause problems even if misused. An innocuous function should have 5259361456Scy** no side effects and should not depend on any values other than its 5260361456Scy** input parameters. The [abs|abs() function] is an example of an 5261361456Scy** innocuous function. 5262361456Scy** The [load_extension() SQL function] is not innocuous because of its 5263361456Scy** side effects. 5264361456Scy** <p> SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not 5265361456Scy** exactly the same. The [random|random() function] is an example of a 5266361456Scy** function that is innocuous but not deterministic. 5267361456Scy** <p>Some heightened security settings 5268361456Scy** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF]) 5269361456Scy** disable the use of SQL functions inside views and triggers and in 5270361456Scy** schema structures such as [CHECK constraints], [DEFAULT clauses], 5271361456Scy** [expression indexes], [partial indexes], and [generated columns] unless 5272361456Scy** the function is tagged with SQLITE_INNOCUOUS. Most built-in functions 5273361456Scy** are innocuous. Developers are advised to avoid using the 5274361456Scy** SQLITE_INNOCUOUS flag for application-defined functions unless the 5275361456Scy** function has been carefully audited and found to be free of potentially 5276361456Scy** security-adverse side-effects and information-leaks. 5277361456Scy** </dd> 5278361456Scy** 5279361456Scy** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd> 5280355326Scy** The SQLITE_SUBTYPE flag indicates to SQLite that a function may call 5281355326Scy** [sqlite3_value_subtype()] to inspect the sub-types of its arguments. 5282355326Scy** Specifying this flag makes no difference for scalar or aggregate user 5283355326Scy** functions. However, if it is not specified for a user-defined window 5284355326Scy** function, then any sub-types belonging to arguments passed to the window 5285355326Scy** function may be discarded before the window function is called (i.e. 5286355326Scy** sqlite3_value_subtype() will always return 0). 5287361456Scy** </dd> 5288361456Scy** </dl> 5289269851Speter*/ 5290355326Scy#define SQLITE_DETERMINISTIC 0x000000800 5291355326Scy#define SQLITE_DIRECTONLY 0x000080000 5292355326Scy#define SQLITE_SUBTYPE 0x000100000 5293361456Scy#define SQLITE_INNOCUOUS 0x000200000 5294269851Speter 5295269851Speter/* 5296251883Speter** CAPI3REF: Deprecated Functions 5297251883Speter** DEPRECATED 5298251883Speter** 5299251883Speter** These functions are [deprecated]. In order to maintain 5300366076Scy** backwards compatibility with older code, these functions continue 5301251883Speter** to be supported. However, new applications should avoid 5302282328Sbapt** the use of these functions. To encourage programmers to avoid 5303282328Sbapt** these functions, we will not explain what they do. 5304251883Speter*/ 5305251883Speter#ifndef SQLITE_OMIT_DEPRECATED 5306322444SpeterSQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*); 5307322444SpeterSQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*); 5308322444SpeterSQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); 5309322444SpeterSQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void); 5310322444SpeterSQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void); 5311322444SpeterSQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int), 5312251883Speter void*,sqlite3_int64); 5313251883Speter#endif 5314251883Speter 5315251883Speter/* 5316286510Speter** CAPI3REF: Obtaining SQL Values 5317286510Speter** METHOD: sqlite3_value 5318251883Speter** 5319322444Speter** <b>Summary:</b> 5320322444Speter** <blockquote><table border=0 cellpadding=0 cellspacing=0> 5321322444Speter** <tr><td><b>sqlite3_value_blob</b><td>→<td>BLOB value 5322322444Speter** <tr><td><b>sqlite3_value_double</b><td>→<td>REAL value 5323322444Speter** <tr><td><b>sqlite3_value_int</b><td>→<td>32-bit INTEGER value 5324322444Speter** <tr><td><b>sqlite3_value_int64</b><td>→<td>64-bit INTEGER value 5325322444Speter** <tr><td><b>sqlite3_value_pointer</b><td>→<td>Pointer value 5326322444Speter** <tr><td><b>sqlite3_value_text</b><td>→<td>UTF-8 TEXT value 5327322444Speter** <tr><td><b>sqlite3_value_text16</b><td>→<td>UTF-16 TEXT value in 5328322444Speter** the native byteorder 5329322444Speter** <tr><td><b>sqlite3_value_text16be</b><td>→<td>UTF-16be TEXT value 5330322444Speter** <tr><td><b>sqlite3_value_text16le</b><td>→<td>UTF-16le TEXT value 5331322444Speter** <tr><td> <td> <td> 5332322444Speter** <tr><td><b>sqlite3_value_bytes</b><td>→<td>Size of a BLOB 5333322444Speter** or a UTF-8 TEXT in bytes 5334322444Speter** <tr><td><b>sqlite3_value_bytes16 </b> 5335322444Speter** <td>→ <td>Size of UTF-16 5336322444Speter** TEXT in bytes 5337322444Speter** <tr><td><b>sqlite3_value_type</b><td>→<td>Default 5338322444Speter** datatype of the value 5339322444Speter** <tr><td><b>sqlite3_value_numeric_type </b> 5340322444Speter** <td>→ <td>Best numeric datatype of the value 5341342292Scy** <tr><td><b>sqlite3_value_nochange </b> 5342342292Scy** <td>→ <td>True if the column is unchanged in an UPDATE 5343342292Scy** against a virtual table. 5344347347Scy** <tr><td><b>sqlite3_value_frombind </b> 5345347347Scy** <td>→ <td>True if value originated from a [bound parameter] 5346322444Speter** </table></blockquote> 5347251883Speter** 5348322444Speter** <b>Details:</b> 5349251883Speter** 5350322444Speter** These routines extract type, size, and content information from 5351322444Speter** [protected sqlite3_value] objects. Protected sqlite3_value objects 5352361456Scy** are used to pass parameter information into the functions that 5353361456Scy** implement [application-defined SQL functions] and [virtual tables]. 5354322444Speter** 5355251883Speter** These routines work only with [protected sqlite3_value] objects. 5356251883Speter** Any attempt to use these routines on an [unprotected sqlite3_value] 5357322444Speter** is not threadsafe. 5358251883Speter** 5359251883Speter** ^These routines work just like the corresponding [column access functions] 5360274884Sbapt** except that these routines take a single [protected sqlite3_value] object 5361251883Speter** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. 5362251883Speter** 5363251883Speter** ^The sqlite3_value_text16() interface extracts a UTF-16 string 5364251883Speter** in the native byte-order of the host machine. ^The 5365251883Speter** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces 5366251883Speter** extract UTF-16 strings as big-endian and little-endian respectively. 5367251883Speter** 5368366076Scy** ^If [sqlite3_value] object V was initialized 5369322444Speter** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)] 5370322444Speter** and if X and Y are strings that compare equal according to strcmp(X,Y), 5371322444Speter** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise, 5372366076Scy** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer() 5373322444Speter** routine is part of the [pointer passing interface] added for SQLite 3.20.0. 5374322444Speter** 5375322444Speter** ^(The sqlite3_value_type(V) interface returns the 5376322444Speter** [SQLITE_INTEGER | datatype code] for the initial datatype of the 5377322444Speter** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER], 5378322444Speter** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^ 5379322444Speter** Other interfaces might change the datatype for an sqlite3_value object. 5380322444Speter** For example, if the datatype is initially SQLITE_INTEGER and 5381322444Speter** sqlite3_value_text(V) is called to extract a text value for that 5382322444Speter** integer, then subsequent calls to sqlite3_value_type(V) might return 5383322444Speter** SQLITE_TEXT. Whether or not a persistent internal datatype conversion 5384322444Speter** occurs is undefined and may change from one release of SQLite to the next. 5385322444Speter** 5386251883Speter** ^(The sqlite3_value_numeric_type() interface attempts to apply 5387251883Speter** numeric affinity to the value. This means that an attempt is 5388251883Speter** made to convert the value to an integer or floating point. If 5389251883Speter** such a conversion is possible without loss of information (in other 5390251883Speter** words, if the value is a string that looks like a number) 5391251883Speter** then the conversion is performed. Otherwise no conversion occurs. 5392251883Speter** The [SQLITE_INTEGER | datatype] after conversion is returned.)^ 5393251883Speter** 5394342292Scy** ^Within the [xUpdate] method of a [virtual table], the 5395342292Scy** sqlite3_value_nochange(X) interface returns true if and only if 5396342292Scy** the column corresponding to X is unchanged by the UPDATE operation 5397342292Scy** that the xUpdate method call was invoked to implement and if 5398342292Scy** and the prior [xColumn] method call that was invoked to extracted 5399342292Scy** the value for that column returned without setting a result (probably 5400342292Scy** because it queried [sqlite3_vtab_nochange()] and found that the column 5401342292Scy** was unchanging). ^Within an [xUpdate] method, any value for which 5402342292Scy** sqlite3_value_nochange(X) is true will in all other respects appear 5403342292Scy** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other 5404342292Scy** than within an [xUpdate] method call for an UPDATE statement, then 5405342292Scy** the return value is arbitrary and meaningless. 5406342292Scy** 5407347347Scy** ^The sqlite3_value_frombind(X) interface returns non-zero if the 5408347347Scy** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()] 5409347347Scy** interfaces. ^If X comes from an SQL literal value, or a table column, 5410361456Scy** or an expression, then sqlite3_value_frombind(X) returns zero. 5411347347Scy** 5412251883Speter** Please pay particular attention to the fact that the pointer returned 5413251883Speter** from [sqlite3_value_blob()], [sqlite3_value_text()], or 5414251883Speter** [sqlite3_value_text16()] can be invalidated by a subsequent call to 5415251883Speter** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], 5416251883Speter** or [sqlite3_value_text16()]. 5417251883Speter** 5418251883Speter** These routines must be called from the same thread as 5419251883Speter** the SQL function that supplied the [sqlite3_value*] parameters. 5420342292Scy** 5421342292Scy** As long as the input parameter is correct, these routines can only 5422342292Scy** fail if an out-of-memory error occurs during a format conversion. 5423342292Scy** Only the following subset of interfaces are subject to out-of-memory 5424342292Scy** errors: 5425342292Scy** 5426342292Scy** <ul> 5427342292Scy** <li> sqlite3_value_blob() 5428342292Scy** <li> sqlite3_value_text() 5429342292Scy** <li> sqlite3_value_text16() 5430342292Scy** <li> sqlite3_value_text16le() 5431342292Scy** <li> sqlite3_value_text16be() 5432342292Scy** <li> sqlite3_value_bytes() 5433342292Scy** <li> sqlite3_value_bytes16() 5434342292Scy** </ul> 5435342292Scy** 5436342292Scy** If an out-of-memory error occurs, then the return value from these 5437342292Scy** routines is the same as if the column had contained an SQL NULL value. 5438342292Scy** Valid SQL NULL returns can be distinguished from out-of-memory errors 5439342292Scy** by invoking the [sqlite3_errcode()] immediately after the suspect 5440342292Scy** return value is obtained and before any 5441342292Scy** other SQLite interface is called on the same [database connection]. 5442251883Speter*/ 5443322444SpeterSQLITE_API const void *sqlite3_value_blob(sqlite3_value*); 5444322444SpeterSQLITE_API double sqlite3_value_double(sqlite3_value*); 5445322444SpeterSQLITE_API int sqlite3_value_int(sqlite3_value*); 5446322444SpeterSQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*); 5447322444SpeterSQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*); 5448322444SpeterSQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*); 5449322444SpeterSQLITE_API const void *sqlite3_value_text16(sqlite3_value*); 5450322444SpeterSQLITE_API const void *sqlite3_value_text16le(sqlite3_value*); 5451322444SpeterSQLITE_API const void *sqlite3_value_text16be(sqlite3_value*); 5452322444SpeterSQLITE_API int sqlite3_value_bytes(sqlite3_value*); 5453322444SpeterSQLITE_API int sqlite3_value_bytes16(sqlite3_value*); 5454322444SpeterSQLITE_API int sqlite3_value_type(sqlite3_value*); 5455322444SpeterSQLITE_API int sqlite3_value_numeric_type(sqlite3_value*); 5456342292ScySQLITE_API int sqlite3_value_nochange(sqlite3_value*); 5457347347ScySQLITE_API int sqlite3_value_frombind(sqlite3_value*); 5458251883Speter 5459251883Speter/* 5460298161Sbapt** CAPI3REF: Finding The Subtype Of SQL Values 5461298161Sbapt** METHOD: sqlite3_value 5462298161Sbapt** 5463298161Sbapt** The sqlite3_value_subtype(V) function returns the subtype for 5464298161Sbapt** an [application-defined SQL function] argument V. The subtype 5465298161Sbapt** information can be used to pass a limited amount of context from 5466298161Sbapt** one SQL function to another. Use the [sqlite3_result_subtype()] 5467298161Sbapt** routine to set the subtype for the return value of an SQL function. 5468298161Sbapt*/ 5469322444SpeterSQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*); 5470298161Sbapt 5471298161Sbapt/* 5472286510Speter** CAPI3REF: Copy And Free SQL Values 5473286510Speter** METHOD: sqlite3_value 5474286510Speter** 5475286510Speter** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value] 5476286510Speter** object D and returns a pointer to that copy. ^The [sqlite3_value] returned 5477286510Speter** is a [protected sqlite3_value] object even if the input is not. 5478286510Speter** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a 5479286510Speter** memory allocation fails. 5480286510Speter** 5481286510Speter** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object 5482286510Speter** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer 5483286510Speter** then sqlite3_value_free(V) is a harmless no-op. 5484286510Speter*/ 5485322444SpeterSQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*); 5486322444SpeterSQLITE_API void sqlite3_value_free(sqlite3_value*); 5487286510Speter 5488286510Speter/* 5489251883Speter** CAPI3REF: Obtain Aggregate Function Context 5490286510Speter** METHOD: sqlite3_context 5491251883Speter** 5492251883Speter** Implementations of aggregate SQL functions use this 5493251883Speter** routine to allocate memory for storing their state. 5494251883Speter** 5495366076Scy** ^The first time the sqlite3_aggregate_context(C,N) routine is called 5496361456Scy** for a particular aggregate function, SQLite allocates 5497361456Scy** N bytes of memory, zeroes out that memory, and returns a pointer 5498251883Speter** to the new memory. ^On second and subsequent calls to 5499251883Speter** sqlite3_aggregate_context() for the same aggregate function instance, 5500251883Speter** the same buffer is returned. Sqlite3_aggregate_context() is normally 5501251883Speter** called once for each invocation of the xStep callback and then one 5502251883Speter** last time when the xFinal callback is invoked. ^(When no rows match 5503251883Speter** an aggregate query, the xStep() callback of the aggregate function 5504251883Speter** implementation is never called and xFinal() is called exactly once. 5505251883Speter** In those cases, sqlite3_aggregate_context() might be called for the 5506251883Speter** first time from within xFinal().)^ 5507251883Speter** 5508366076Scy** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer 5509251883Speter** when first called if N is less than or equal to zero or if a memory 5510251883Speter** allocate error occurs. 5511251883Speter** 5512251883Speter** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is 5513251883Speter** determined by the N parameter on first successful call. Changing the 5514362190Scy** value of N in any subsequent call to sqlite3_aggregate_context() within 5515251883Speter** the same aggregate function instance will not resize the memory 5516251883Speter** allocation.)^ Within the xFinal callback, it is customary to set 5517366076Scy** N=0 in calls to sqlite3_aggregate_context(C,N) so that no 5518251883Speter** pointless memory allocations occur. 5519251883Speter** 5520366076Scy** ^SQLite automatically frees the memory allocated by 5521251883Speter** sqlite3_aggregate_context() when the aggregate query concludes. 5522251883Speter** 5523251883Speter** The first parameter must be a copy of the 5524251883Speter** [sqlite3_context | SQL function context] that is the first parameter 5525251883Speter** to the xStep or xFinal callback routine that implements the aggregate 5526251883Speter** function. 5527251883Speter** 5528251883Speter** This routine must be called from the same thread in which 5529251883Speter** the aggregate SQL function is running. 5530251883Speter*/ 5531322444SpeterSQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); 5532251883Speter 5533251883Speter/* 5534251883Speter** CAPI3REF: User Data For Functions 5535286510Speter** METHOD: sqlite3_context 5536251883Speter** 5537251883Speter** ^The sqlite3_user_data() interface returns a copy of 5538251883Speter** the pointer that was the pUserData parameter (the 5th parameter) 5539251883Speter** of the [sqlite3_create_function()] 5540251883Speter** and [sqlite3_create_function16()] routines that originally 5541251883Speter** registered the application defined function. 5542251883Speter** 5543251883Speter** This routine must be called from the same thread in which 5544251883Speter** the application-defined function is running. 5545251883Speter*/ 5546322444SpeterSQLITE_API void *sqlite3_user_data(sqlite3_context*); 5547251883Speter 5548251883Speter/* 5549251883Speter** CAPI3REF: Database Connection For Functions 5550286510Speter** METHOD: sqlite3_context 5551251883Speter** 5552251883Speter** ^The sqlite3_context_db_handle() interface returns a copy of 5553251883Speter** the pointer to the [database connection] (the 1st parameter) 5554251883Speter** of the [sqlite3_create_function()] 5555251883Speter** and [sqlite3_create_function16()] routines that originally 5556251883Speter** registered the application defined function. 5557251883Speter*/ 5558322444SpeterSQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*); 5559251883Speter 5560251883Speter/* 5561251883Speter** CAPI3REF: Function Auxiliary Data 5562286510Speter** METHOD: sqlite3_context 5563251883Speter** 5564269851Speter** These functions may be used by (non-aggregate) SQL functions to 5565251883Speter** associate metadata with argument values. If the same value is passed to 5566251883Speter** multiple invocations of the same SQL function during query execution, under 5567269851Speter** some circumstances the associated metadata may be preserved. An example 5568269851Speter** of where this might be useful is in a regular-expression matching 5569269851Speter** function. The compiled version of the regular expression can be stored as 5570366076Scy** metadata associated with the pattern string. 5571269851Speter** Then as long as the pattern string remains the same, 5572269851Speter** the compiled regular expression can be reused on multiple 5573269851Speter** invocations of the same function. 5574251883Speter** 5575322444Speter** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the metadata 5576322444Speter** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument 5577322444Speter** value to the application-defined function. ^N is zero for the left-most 5578322444Speter** function argument. ^If there is no metadata 5579322444Speter** associated with the function argument, the sqlite3_get_auxdata(C,N) interface 5580269851Speter** returns a NULL pointer. 5581251883Speter** 5582269851Speter** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th 5583269851Speter** argument of the application-defined function. ^Subsequent 5584269851Speter** calls to sqlite3_get_auxdata(C,N) return P from the most recent 5585269851Speter** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or 5586269851Speter** NULL if the metadata has been discarded. 5587269851Speter** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL, 5588269851Speter** SQLite will invoke the destructor function X with parameter P exactly 5589269851Speter** once, when the metadata is discarded. 5590269851Speter** SQLite is free to discard the metadata at any time, including: <ul> 5591305002Scy** <li> ^(when the corresponding function parameter changes)^, or 5592305002Scy** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the 5593305002Scy** SQL statement)^, or 5594305002Scy** <li> ^(when sqlite3_set_auxdata() is invoked again on the same 5595305002Scy** parameter)^, or 5596366076Scy** <li> ^(during the original sqlite3_set_auxdata() call when a memory 5597305002Scy** allocation error occurs.)^ </ul> 5598251883Speter** 5599366076Scy** Note the last bullet in particular. The destructor X in 5600269851Speter** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the 5601269851Speter** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata() 5602269851Speter** should be called near the end of the function implementation and the 5603269851Speter** function implementation should not make any use of P after 5604269851Speter** sqlite3_set_auxdata() has been called. 5605251883Speter** 5606251883Speter** ^(In practice, metadata is preserved between function calls for 5607269851Speter** function parameters that are compile-time constants, including literal 5608269851Speter** values and [parameters] and expressions composed from the same.)^ 5609251883Speter** 5610322444Speter** The value of the N parameter to these interfaces should be non-negative. 5611322444Speter** Future enhancements may make use of negative N values to define new 5612322444Speter** kinds of function caching behavior. 5613322444Speter** 5614251883Speter** These routines must be called from the same thread in which 5615251883Speter** the SQL function is running. 5616251883Speter*/ 5617322444SpeterSQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N); 5618322444SpeterSQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); 5619251883Speter 5620251883Speter 5621251883Speter/* 5622251883Speter** CAPI3REF: Constants Defining Special Destructor Behavior 5623251883Speter** 5624251883Speter** These are special values for the destructor that is passed in as the 5625251883Speter** final argument to routines like [sqlite3_result_blob()]. ^If the destructor 5626251883Speter** argument is SQLITE_STATIC, it means that the content pointer is constant 5627251883Speter** and will never change. It does not need to be destroyed. ^The 5628251883Speter** SQLITE_TRANSIENT value means that the content will likely change in 5629251883Speter** the near future and that SQLite should make its own private copy of 5630251883Speter** the content before returning. 5631251883Speter** 5632251883Speter** The typedef is necessary to work around problems in certain 5633251883Speter** C++ compilers. 5634251883Speter*/ 5635251883Spetertypedef void (*sqlite3_destructor_type)(void*); 5636251883Speter#define SQLITE_STATIC ((sqlite3_destructor_type)0) 5637251883Speter#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) 5638251883Speter 5639251883Speter/* 5640251883Speter** CAPI3REF: Setting The Result Of An SQL Function 5641286510Speter** METHOD: sqlite3_context 5642251883Speter** 5643251883Speter** These routines are used by the xFunc or xFinal callbacks that 5644251883Speter** implement SQL functions and aggregates. See 5645251883Speter** [sqlite3_create_function()] and [sqlite3_create_function16()] 5646251883Speter** for additional information. 5647251883Speter** 5648251883Speter** These functions work very much like the [parameter binding] family of 5649251883Speter** functions used to bind values to host parameters in prepared statements. 5650251883Speter** Refer to the [SQL parameter] documentation for additional information. 5651251883Speter** 5652251883Speter** ^The sqlite3_result_blob() interface sets the result from 5653251883Speter** an application-defined function to be the BLOB whose content is pointed 5654251883Speter** to by the second parameter and which is N bytes long where N is the 5655251883Speter** third parameter. 5656251883Speter** 5657286510Speter** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N) 5658286510Speter** interfaces set the result of the application-defined function to be 5659286510Speter** a BLOB containing all zero bytes and N bytes in size. 5660251883Speter** 5661251883Speter** ^The sqlite3_result_double() interface sets the result from 5662251883Speter** an application-defined function to be a floating point value specified 5663251883Speter** by its 2nd argument. 5664251883Speter** 5665251883Speter** ^The sqlite3_result_error() and sqlite3_result_error16() functions 5666251883Speter** cause the implemented SQL function to throw an exception. 5667251883Speter** ^SQLite uses the string pointed to by the 5668251883Speter** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() 5669251883Speter** as the text of an error message. ^SQLite interprets the error 5670251883Speter** message string from sqlite3_result_error() as UTF-8. ^SQLite 5671362190Scy** interprets the string from sqlite3_result_error16() as UTF-16 using 5672362190Scy** the same [byte-order determination rules] as [sqlite3_bind_text16()]. 5673362190Scy** ^If the third parameter to sqlite3_result_error() 5674251883Speter** or sqlite3_result_error16() is negative then SQLite takes as the error 5675251883Speter** message all text up through the first zero character. 5676251883Speter** ^If the third parameter to sqlite3_result_error() or 5677251883Speter** sqlite3_result_error16() is non-negative then SQLite takes that many 5678251883Speter** bytes (not characters) from the 2nd parameter as the error message. 5679251883Speter** ^The sqlite3_result_error() and sqlite3_result_error16() 5680251883Speter** routines make a private copy of the error message text before 5681251883Speter** they return. Hence, the calling function can deallocate or 5682251883Speter** modify the text after they return without harm. 5683251883Speter** ^The sqlite3_result_error_code() function changes the error code 5684251883Speter** returned by SQLite as a result of an error in a function. ^By default, 5685251883Speter** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error() 5686251883Speter** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. 5687251883Speter** 5688251883Speter** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an 5689251883Speter** error indicating that a string or BLOB is too long to represent. 5690251883Speter** 5691251883Speter** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an 5692251883Speter** error indicating that a memory allocation failed. 5693251883Speter** 5694251883Speter** ^The sqlite3_result_int() interface sets the return value 5695251883Speter** of the application-defined function to be the 32-bit signed integer 5696251883Speter** value given in the 2nd argument. 5697251883Speter** ^The sqlite3_result_int64() interface sets the return value 5698251883Speter** of the application-defined function to be the 64-bit signed integer 5699251883Speter** value given in the 2nd argument. 5700251883Speter** 5701251883Speter** ^The sqlite3_result_null() interface sets the return value 5702251883Speter** of the application-defined function to be NULL. 5703251883Speter** 5704251883Speter** ^The sqlite3_result_text(), sqlite3_result_text16(), 5705251883Speter** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces 5706251883Speter** set the return value of the application-defined function to be 5707251883Speter** a text string which is represented as UTF-8, UTF-16 native byte order, 5708251883Speter** UTF-16 little endian, or UTF-16 big endian, respectively. 5709274884Sbapt** ^The sqlite3_result_text64() interface sets the return value of an 5710274884Sbapt** application-defined function to be a text string in an encoding 5711274884Sbapt** specified by the fifth (and last) parameter, which must be one 5712274884Sbapt** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]. 5713251883Speter** ^SQLite takes the text result from the application from 5714251883Speter** the 2nd parameter of the sqlite3_result_text* interfaces. 5715251883Speter** ^If the 3rd parameter to the sqlite3_result_text* interfaces 5716251883Speter** is negative, then SQLite takes result text from the 2nd parameter 5717251883Speter** through the first zero character. 5718251883Speter** ^If the 3rd parameter to the sqlite3_result_text* interfaces 5719251883Speter** is non-negative, then as many bytes (not characters) of the text 5720251883Speter** pointed to by the 2nd parameter are taken as the application-defined 5721251883Speter** function result. If the 3rd parameter is non-negative, then it 5722251883Speter** must be the byte offset into the string where the NUL terminator would 5723251883Speter** appear if the string where NUL terminated. If any NUL characters occur 5724251883Speter** in the string at a byte offset that is less than the value of the 3rd 5725251883Speter** parameter, then the resulting string will contain embedded NULs and the 5726251883Speter** result of expressions operating on strings with embedded NULs is undefined. 5727251883Speter** ^If the 4th parameter to the sqlite3_result_text* interfaces 5728251883Speter** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that 5729251883Speter** function as the destructor on the text or BLOB result when it has 5730251883Speter** finished using that result. 5731251883Speter** ^If the 4th parameter to the sqlite3_result_text* interfaces or to 5732251883Speter** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite 5733251883Speter** assumes that the text or BLOB result is in constant space and does not 5734251883Speter** copy the content of the parameter nor call a destructor on the content 5735251883Speter** when it has finished using that result. 5736251883Speter** ^If the 4th parameter to the sqlite3_result_text* interfaces 5737251883Speter** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT 5738322444Speter** then SQLite makes a copy of the result into space obtained 5739251883Speter** from [sqlite3_malloc()] before it returns. 5740251883Speter** 5741362190Scy** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and 5742362190Scy** sqlite3_result_text16be() routines, and for sqlite3_result_text64() 5743362190Scy** when the encoding is not UTF8, if the input UTF16 begins with a 5744362190Scy** byte-order mark (BOM, U+FEFF) then the BOM is removed from the 5745362190Scy** string and the rest of the string is interpreted according to the 5746362190Scy** byte-order specified by the BOM. ^The byte-order specified by 5747362190Scy** the BOM at the beginning of the text overrides the byte-order 5748362190Scy** specified by the interface procedure. ^So, for example, if 5749362190Scy** sqlite3_result_text16le() is invoked with text that begins 5750362190Scy** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the 5751362190Scy** first two bytes of input are skipped and the remaining input 5752362190Scy** is interpreted as UTF16BE text. 5753362190Scy** 5754362190Scy** ^For UTF16 input text to the sqlite3_result_text16(), 5755362190Scy** sqlite3_result_text16be(), sqlite3_result_text16le(), and 5756362190Scy** sqlite3_result_text64() routines, if the text contains invalid 5757362190Scy** UTF16 characters, the invalid characters might be converted 5758362190Scy** into the unicode replacement character, U+FFFD. 5759362190Scy** 5760251883Speter** ^The sqlite3_result_value() interface sets the result of 5761286510Speter** the application-defined function to be a copy of the 5762251883Speter** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The 5763251883Speter** sqlite3_result_value() interface makes a copy of the [sqlite3_value] 5764251883Speter** so that the [sqlite3_value] specified in the parameter may change or 5765251883Speter** be deallocated after sqlite3_result_value() returns without harm. 5766251883Speter** ^A [protected sqlite3_value] object may always be used where an 5767251883Speter** [unprotected sqlite3_value] object is required, so either 5768251883Speter** kind of [sqlite3_value] object can be used with this interface. 5769251883Speter** 5770322444Speter** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an 5771322444Speter** SQL NULL value, just like [sqlite3_result_null(C)], except that it 5772366076Scy** also associates the host-language pointer P or type T with that 5773322444Speter** NULL value such that the pointer can be retrieved within an 5774322444Speter** [application-defined SQL function] using [sqlite3_value_pointer()]. 5775322444Speter** ^If the D parameter is not NULL, then it is a pointer to a destructor 5776322444Speter** for the P parameter. ^SQLite invokes D with P as its only argument 5777322444Speter** when SQLite is finished with P. The T parameter should be a static 5778322444Speter** string and preferably a string literal. The sqlite3_result_pointer() 5779322444Speter** routine is part of the [pointer passing interface] added for SQLite 3.20.0. 5780322444Speter** 5781251883Speter** If these routines are called from within the different thread 5782251883Speter** than the one containing the application-defined function that received 5783251883Speter** the [sqlite3_context] pointer, the results are undefined. 5784251883Speter*/ 5785322444SpeterSQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); 5786322444SpeterSQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*, 5787282328Sbapt sqlite3_uint64,void(*)(void*)); 5788322444SpeterSQLITE_API void sqlite3_result_double(sqlite3_context*, double); 5789322444SpeterSQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int); 5790322444SpeterSQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int); 5791322444SpeterSQLITE_API void sqlite3_result_error_toobig(sqlite3_context*); 5792322444SpeterSQLITE_API void sqlite3_result_error_nomem(sqlite3_context*); 5793322444SpeterSQLITE_API void sqlite3_result_error_code(sqlite3_context*, int); 5794322444SpeterSQLITE_API void sqlite3_result_int(sqlite3_context*, int); 5795322444SpeterSQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); 5796322444SpeterSQLITE_API void sqlite3_result_null(sqlite3_context*); 5797322444SpeterSQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); 5798322444SpeterSQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64, 5799274884Sbapt void(*)(void*), unsigned char encoding); 5800322444SpeterSQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); 5801322444SpeterSQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); 5802322444SpeterSQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); 5803322444SpeterSQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*); 5804322444SpeterSQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*)); 5805322444SpeterSQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n); 5806322444SpeterSQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n); 5807251883Speter 5808298161Sbapt 5809251883Speter/* 5810298161Sbapt** CAPI3REF: Setting The Subtype Of An SQL Function 5811298161Sbapt** METHOD: sqlite3_context 5812298161Sbapt** 5813298161Sbapt** The sqlite3_result_subtype(C,T) function causes the subtype of 5814366076Scy** the result from the [application-defined SQL function] with 5815366076Scy** [sqlite3_context] C to be the value T. Only the lower 8 bits 5816298161Sbapt** of the subtype T are preserved in current versions of SQLite; 5817298161Sbapt** higher order bits are discarded. 5818298161Sbapt** The number of subtype bytes preserved by SQLite might increase 5819298161Sbapt** in future releases of SQLite. 5820298161Sbapt*/ 5821322444SpeterSQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int); 5822298161Sbapt 5823298161Sbapt/* 5824251883Speter** CAPI3REF: Define New Collating Sequences 5825286510Speter** METHOD: sqlite3 5826251883Speter** 5827251883Speter** ^These functions add, remove, or modify a [collation] associated 5828251883Speter** with the [database connection] specified as the first argument. 5829251883Speter** 5830251883Speter** ^The name of the collation is a UTF-8 string 5831251883Speter** for sqlite3_create_collation() and sqlite3_create_collation_v2() 5832251883Speter** and a UTF-16 string in native byte order for sqlite3_create_collation16(). 5833251883Speter** ^Collation names that compare equal according to [sqlite3_strnicmp()] are 5834251883Speter** considered to be the same name. 5835251883Speter** 5836251883Speter** ^(The third argument (eTextRep) must be one of the constants: 5837251883Speter** <ul> 5838251883Speter** <li> [SQLITE_UTF8], 5839251883Speter** <li> [SQLITE_UTF16LE], 5840251883Speter** <li> [SQLITE_UTF16BE], 5841251883Speter** <li> [SQLITE_UTF16], or 5842251883Speter** <li> [SQLITE_UTF16_ALIGNED]. 5843251883Speter** </ul>)^ 5844251883Speter** ^The eTextRep argument determines the encoding of strings passed 5845361456Scy** to the collating function callback, xCompare. 5846251883Speter** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep 5847251883Speter** force strings to be UTF16 with native byte order. 5848251883Speter** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin 5849251883Speter** on an even byte address. 5850251883Speter** 5851251883Speter** ^The fourth argument, pArg, is an application data pointer that is passed 5852251883Speter** through as the first argument to the collating function callback. 5853251883Speter** 5854361456Scy** ^The fifth argument, xCompare, is a pointer to the collating function. 5855251883Speter** ^Multiple collating functions can be registered using the same name but 5856251883Speter** with different eTextRep parameters and SQLite will use whichever 5857251883Speter** function requires the least amount of data transformation. 5858361456Scy** ^If the xCompare argument is NULL then the collating function is 5859251883Speter** deleted. ^When all collating functions having the same name are deleted, 5860251883Speter** that collation is no longer usable. 5861251883Speter** 5862366076Scy** ^The collating function callback is invoked with a copy of the pArg 5863251883Speter** application data pointer and with two strings in the encoding specified 5864361456Scy** by the eTextRep argument. The two integer parameters to the collating 5865361456Scy** function callback are the length of the two strings, in bytes. The collating 5866361456Scy** function must return an integer that is negative, zero, or positive 5867251883Speter** if the first string is less than, equal to, or greater than the second, 5868251883Speter** respectively. A collating function must always return the same answer 5869251883Speter** given the same inputs. If two or more collating functions are registered 5870251883Speter** to the same collation name (using different eTextRep values) then all 5871251883Speter** must give an equivalent answer when invoked with equivalent strings. 5872251883Speter** The collating function must obey the following properties for all 5873251883Speter** strings A, B, and C: 5874251883Speter** 5875251883Speter** <ol> 5876251883Speter** <li> If A==B then B==A. 5877251883Speter** <li> If A==B and B==C then A==C. 5878251883Speter** <li> If A<B THEN B>A. 5879251883Speter** <li> If A<B and B<C then A<C. 5880251883Speter** </ol> 5881251883Speter** 5882251883Speter** If a collating function fails any of the above constraints and that 5883361456Scy** collating function is registered and used, then the behavior of SQLite 5884251883Speter** is undefined. 5885251883Speter** 5886251883Speter** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation() 5887251883Speter** with the addition that the xDestroy callback is invoked on pArg when 5888251883Speter** the collating function is deleted. 5889251883Speter** ^Collating functions are deleted when they are overridden by later 5890251883Speter** calls to the collation creation functions or when the 5891251883Speter** [database connection] is closed using [sqlite3_close()]. 5892251883Speter** 5893366076Scy** ^The xDestroy callback is <u>not</u> called if the 5894251883Speter** sqlite3_create_collation_v2() function fails. Applications that invoke 5895366076Scy** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should 5896251883Speter** check the return code and dispose of the application data pointer 5897251883Speter** themselves rather than expecting SQLite to deal with it for them. 5898366076Scy** This is different from every other SQLite interface. The inconsistency 5899366076Scy** is unfortunate but cannot be changed without breaking backwards 5900251883Speter** compatibility. 5901251883Speter** 5902251883Speter** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()]. 5903251883Speter*/ 5904322444SpeterSQLITE_API int sqlite3_create_collation( 5905366076Scy sqlite3*, 5906366076Scy const char *zName, 5907366076Scy int eTextRep, 5908251883Speter void *pArg, 5909251883Speter int(*xCompare)(void*,int,const void*,int,const void*) 5910251883Speter); 5911322444SpeterSQLITE_API int sqlite3_create_collation_v2( 5912366076Scy sqlite3*, 5913366076Scy const char *zName, 5914366076Scy int eTextRep, 5915251883Speter void *pArg, 5916251883Speter int(*xCompare)(void*,int,const void*,int,const void*), 5917251883Speter void(*xDestroy)(void*) 5918251883Speter); 5919322444SpeterSQLITE_API int sqlite3_create_collation16( 5920366076Scy sqlite3*, 5921251883Speter const void *zName, 5922366076Scy int eTextRep, 5923251883Speter void *pArg, 5924251883Speter int(*xCompare)(void*,int,const void*,int,const void*) 5925251883Speter); 5926251883Speter 5927251883Speter/* 5928251883Speter** CAPI3REF: Collation Needed Callbacks 5929286510Speter** METHOD: sqlite3 5930251883Speter** 5931251883Speter** ^To avoid having to register all collation sequences before a database 5932251883Speter** can be used, a single callback function may be registered with the 5933251883Speter** [database connection] to be invoked whenever an undefined collation 5934251883Speter** sequence is required. 5935251883Speter** 5936251883Speter** ^If the function is registered using the sqlite3_collation_needed() API, 5937251883Speter** then it is passed the names of undefined collation sequences as strings 5938251883Speter** encoded in UTF-8. ^If sqlite3_collation_needed16() is used, 5939251883Speter** the names are passed as UTF-16 in machine native byte order. 5940251883Speter** ^A call to either function replaces the existing collation-needed callback. 5941251883Speter** 5942251883Speter** ^(When the callback is invoked, the first argument passed is a copy 5943251883Speter** of the second argument to sqlite3_collation_needed() or 5944251883Speter** sqlite3_collation_needed16(). The second argument is the database 5945251883Speter** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], 5946251883Speter** or [SQLITE_UTF16LE], indicating the most desirable form of the collation 5947251883Speter** sequence function required. The fourth parameter is the name of the 5948251883Speter** required collation sequence.)^ 5949251883Speter** 5950251883Speter** The callback function should register the desired collation using 5951251883Speter** [sqlite3_create_collation()], [sqlite3_create_collation16()], or 5952251883Speter** [sqlite3_create_collation_v2()]. 5953251883Speter*/ 5954322444SpeterSQLITE_API int sqlite3_collation_needed( 5955366076Scy sqlite3*, 5956366076Scy void*, 5957251883Speter void(*)(void*,sqlite3*,int eTextRep,const char*) 5958251883Speter); 5959322444SpeterSQLITE_API int sqlite3_collation_needed16( 5960366076Scy sqlite3*, 5961251883Speter void*, 5962251883Speter void(*)(void*,sqlite3*,int eTextRep,const void*) 5963251883Speter); 5964251883Speter 5965251883Speter#ifdef SQLITE_ENABLE_CEROD 5966251883Speter/* 5967366076Scy** Specify the activation key for a CEROD database. Unless 5968251883Speter** activated, none of the CEROD routines will work. 5969251883Speter*/ 5970322444SpeterSQLITE_API void sqlite3_activate_cerod( 5971251883Speter const char *zPassPhrase /* Activation phrase */ 5972251883Speter); 5973251883Speter#endif 5974251883Speter 5975251883Speter/* 5976251883Speter** CAPI3REF: Suspend Execution For A Short Time 5977251883Speter** 5978251883Speter** The sqlite3_sleep() function causes the current thread to suspend execution 5979251883Speter** for at least a number of milliseconds specified in its parameter. 5980251883Speter** 5981251883Speter** If the operating system does not support sleep requests with 5982251883Speter** millisecond time resolution, then the time will be rounded up to 5983251883Speter** the nearest second. The number of milliseconds of sleep actually 5984251883Speter** requested from the operating system is returned. 5985251883Speter** 5986251883Speter** ^SQLite implements this interface by calling the xSleep() 5987251883Speter** method of the default [sqlite3_vfs] object. If the xSleep() method 5988251883Speter** of the default VFS is not implemented correctly, or not implemented at 5989251883Speter** all, then the behavior of sqlite3_sleep() may deviate from the description 5990251883Speter** in the previous paragraphs. 5991251883Speter*/ 5992322444SpeterSQLITE_API int sqlite3_sleep(int); 5993251883Speter 5994251883Speter/* 5995251883Speter** CAPI3REF: Name Of The Folder Holding Temporary Files 5996251883Speter** 5997251883Speter** ^(If this global variable is made to point to a string which is 5998251883Speter** the name of a folder (a.k.a. directory), then all temporary files 5999251883Speter** created by SQLite when using a built-in [sqlite3_vfs | VFS] 6000251883Speter** will be placed in that directory.)^ ^If this variable 6001251883Speter** is a NULL pointer, then SQLite performs a search for an appropriate 6002251883Speter** temporary file directory. 6003251883Speter** 6004274884Sbapt** Applications are strongly discouraged from using this global variable. 6005274884Sbapt** It is required to set a temporary folder on Windows Runtime (WinRT). 6006274884Sbapt** But for all other platforms, it is highly recommended that applications 6007274884Sbapt** neither read nor write this variable. This global variable is a relic 6008274884Sbapt** that exists for backwards compatibility of legacy applications and should 6009274884Sbapt** be avoided in new projects. 6010274884Sbapt** 6011251883Speter** It is not safe to read or modify this variable in more than one 6012251883Speter** thread at a time. It is not safe to read or modify this variable 6013251883Speter** if a [database connection] is being used at the same time in a separate 6014251883Speter** thread. 6015251883Speter** It is intended that this variable be set once 6016251883Speter** as part of process initialization and before any SQLite interface 6017251883Speter** routines have been called and that this variable remain unchanged 6018251883Speter** thereafter. 6019251883Speter** 6020251883Speter** ^The [temp_store_directory pragma] may modify this variable and cause 6021251883Speter** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 6022251883Speter** the [temp_store_directory pragma] always assumes that any string 6023366076Scy** that this variable points to is held in memory obtained from 6024251883Speter** [sqlite3_malloc] and the pragma may attempt to free that memory 6025251883Speter** using [sqlite3_free]. 6026251883Speter** Hence, if this variable is modified directly, either it should be 6027251883Speter** made NULL or made to point to memory obtained from [sqlite3_malloc] 6028251883Speter** or else the use of the [temp_store_directory pragma] should be avoided. 6029274884Sbapt** Except when requested by the [temp_store_directory pragma], SQLite 6030274884Sbapt** does not free the memory that sqlite3_temp_directory points to. If 6031274884Sbapt** the application wants that memory to be freed, it must do 6032274884Sbapt** so itself, taking care to only do so after all [database connection] 6033274884Sbapt** objects have been destroyed. 6034251883Speter** 6035251883Speter** <b>Note to Windows Runtime users:</b> The temporary directory must be set 6036251883Speter** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various 6037251883Speter** features that require the use of temporary files may fail. Here is an 6038251883Speter** example of how to do this using C++ with the Windows Runtime: 6039251883Speter** 6040251883Speter** <blockquote><pre> 6041251883Speter** LPCWSTR zPath = Windows::Storage::ApplicationData::Current-> 6042251883Speter** TemporaryFolder->Path->Data(); 6043251883Speter** char zPathBuf[MAX_PATH + 1]; 6044251883Speter** memset(zPathBuf, 0, sizeof(zPathBuf)); 6045251883Speter** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf), 6046251883Speter** NULL, NULL); 6047251883Speter** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf); 6048251883Speter** </pre></blockquote> 6049251883Speter*/ 6050251883SpeterSQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory; 6051251883Speter 6052251883Speter/* 6053251883Speter** CAPI3REF: Name Of The Folder Holding Database Files 6054251883Speter** 6055251883Speter** ^(If this global variable is made to point to a string which is 6056251883Speter** the name of a folder (a.k.a. directory), then all database files 6057251883Speter** specified with a relative pathname and created or accessed by 6058251883Speter** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed 6059251883Speter** to be relative to that directory.)^ ^If this variable is a NULL 6060251883Speter** pointer, then SQLite assumes that all database files specified 6061251883Speter** with a relative pathname are relative to the current directory 6062251883Speter** for the process. Only the windows VFS makes use of this global 6063251883Speter** variable; it is ignored by the unix VFS. 6064251883Speter** 6065251883Speter** Changing the value of this variable while a database connection is 6066251883Speter** open can result in a corrupt database. 6067251883Speter** 6068251883Speter** It is not safe to read or modify this variable in more than one 6069251883Speter** thread at a time. It is not safe to read or modify this variable 6070251883Speter** if a [database connection] is being used at the same time in a separate 6071251883Speter** thread. 6072251883Speter** It is intended that this variable be set once 6073251883Speter** as part of process initialization and before any SQLite interface 6074251883Speter** routines have been called and that this variable remain unchanged 6075251883Speter** thereafter. 6076251883Speter** 6077251883Speter** ^The [data_store_directory pragma] may modify this variable and cause 6078251883Speter** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 6079251883Speter** the [data_store_directory pragma] always assumes that any string 6080366076Scy** that this variable points to is held in memory obtained from 6081251883Speter** [sqlite3_malloc] and the pragma may attempt to free that memory 6082251883Speter** using [sqlite3_free]. 6083251883Speter** Hence, if this variable is modified directly, either it should be 6084251883Speter** made NULL or made to point to memory obtained from [sqlite3_malloc] 6085251883Speter** or else the use of the [data_store_directory pragma] should be avoided. 6086251883Speter*/ 6087251883SpeterSQLITE_API SQLITE_EXTERN char *sqlite3_data_directory; 6088251883Speter 6089251883Speter/* 6090342292Scy** CAPI3REF: Win32 Specific Interface 6091342292Scy** 6092342292Scy** These interfaces are available only on Windows. The 6093342292Scy** [sqlite3_win32_set_directory] interface is used to set the value associated 6094342292Scy** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to 6095342292Scy** zValue, depending on the value of the type parameter. The zValue parameter 6096342292Scy** should be NULL to cause the previous value to be freed via [sqlite3_free]; 6097342292Scy** a non-NULL value will be copied into memory obtained from [sqlite3_malloc] 6098342292Scy** prior to being used. The [sqlite3_win32_set_directory] interface returns 6099342292Scy** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported, 6100342292Scy** or [SQLITE_NOMEM] if memory could not be allocated. The value of the 6101342292Scy** [sqlite3_data_directory] variable is intended to act as a replacement for 6102342292Scy** the current directory on the sub-platforms of Win32 where that concept is 6103342292Scy** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and 6104342292Scy** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the 6105342292Scy** sqlite3_win32_set_directory interface except the string parameter must be 6106342292Scy** UTF-8 or UTF-16, respectively. 6107342292Scy*/ 6108342292ScySQLITE_API int sqlite3_win32_set_directory( 6109342292Scy unsigned long type, /* Identifier for directory being set or reset */ 6110342292Scy void *zValue /* New value for directory being set or reset */ 6111342292Scy); 6112342292ScySQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue); 6113342292ScySQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue); 6114342292Scy 6115342292Scy/* 6116342292Scy** CAPI3REF: Win32 Directory Types 6117342292Scy** 6118342292Scy** These macros are only available on Windows. They define the allowed values 6119342292Scy** for the type argument to the [sqlite3_win32_set_directory] interface. 6120342292Scy*/ 6121342292Scy#define SQLITE_WIN32_DATA_DIRECTORY_TYPE 1 6122342292Scy#define SQLITE_WIN32_TEMP_DIRECTORY_TYPE 2 6123342292Scy 6124342292Scy/* 6125251883Speter** CAPI3REF: Test For Auto-Commit Mode 6126251883Speter** KEYWORDS: {autocommit mode} 6127286510Speter** METHOD: sqlite3 6128251883Speter** 6129251883Speter** ^The sqlite3_get_autocommit() interface returns non-zero or 6130251883Speter** zero if the given database connection is or is not in autocommit mode, 6131251883Speter** respectively. ^Autocommit mode is on by default. 6132251883Speter** ^Autocommit mode is disabled by a [BEGIN] statement. 6133251883Speter** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. 6134251883Speter** 6135251883Speter** If certain kinds of errors occur on a statement within a multi-statement 6136251883Speter** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], 6137251883Speter** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the 6138251883Speter** transaction might be rolled back automatically. The only way to 6139251883Speter** find out whether SQLite automatically rolled back the transaction after 6140251883Speter** an error is to use this function. 6141251883Speter** 6142251883Speter** If another thread changes the autocommit status of the database 6143251883Speter** connection while this routine is running, then the return value 6144251883Speter** is undefined. 6145251883Speter*/ 6146322444SpeterSQLITE_API int sqlite3_get_autocommit(sqlite3*); 6147251883Speter 6148251883Speter/* 6149251883Speter** CAPI3REF: Find The Database Handle Of A Prepared Statement 6150286510Speter** METHOD: sqlite3_stmt 6151251883Speter** 6152251883Speter** ^The sqlite3_db_handle interface returns the [database connection] handle 6153251883Speter** to which a [prepared statement] belongs. ^The [database connection] 6154251883Speter** returned by sqlite3_db_handle is the same [database connection] 6155251883Speter** that was the first argument 6156251883Speter** to the [sqlite3_prepare_v2()] call (or its variants) that was used to 6157251883Speter** create the statement in the first place. 6158251883Speter*/ 6159322444SpeterSQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*); 6160251883Speter 6161251883Speter/* 6162251883Speter** CAPI3REF: Return The Filename For A Database Connection 6163286510Speter** METHOD: sqlite3 6164251883Speter** 6165361456Scy** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename 6166361456Scy** associated with database N of connection D. 6167361456Scy** ^If there is no attached database N on the database 6168251883Speter** connection D, or if database N is a temporary or in-memory database, then 6169347347Scy** this function will return either a NULL pointer or an empty string. 6170251883Speter** 6171361456Scy** ^The string value returned by this routine is owned and managed by 6172361456Scy** the database connection. ^The value will be valid until the database N 6173361456Scy** is [DETACH]-ed or until the database connection closes. 6174361456Scy** 6175251883Speter** ^The filename returned by this function is the output of the 6176251883Speter** xFullPathname method of the [VFS]. ^In other words, the filename 6177251883Speter** will be an absolute pathname, even if the filename used 6178251883Speter** to open the database originally was a URI or relative pathname. 6179361456Scy** 6180361456Scy** If the filename pointer returned by this routine is not NULL, then it 6181361456Scy** can be used as the filename input parameter to these routines: 6182361456Scy** <ul> 6183361456Scy** <li> [sqlite3_uri_parameter()] 6184361456Scy** <li> [sqlite3_uri_boolean()] 6185361456Scy** <li> [sqlite3_uri_int64()] 6186361456Scy** <li> [sqlite3_filename_database()] 6187361456Scy** <li> [sqlite3_filename_journal()] 6188361456Scy** <li> [sqlite3_filename_wal()] 6189361456Scy** </ul> 6190251883Speter*/ 6191322444SpeterSQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName); 6192251883Speter 6193251883Speter/* 6194251883Speter** CAPI3REF: Determine if a database is read-only 6195286510Speter** METHOD: sqlite3 6196251883Speter** 6197251883Speter** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N 6198251883Speter** of connection D is read-only, 0 if it is read/write, or -1 if N is not 6199251883Speter** the name of a database on connection D. 6200251883Speter*/ 6201322444SpeterSQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName); 6202251883Speter 6203251883Speter/* 6204369950Scy** CAPI3REF: Determine the transaction state of a database 6205369950Scy** METHOD: sqlite3 6206369950Scy** 6207369950Scy** ^The sqlite3_txn_state(D,S) interface returns the current 6208369950Scy** [transaction state] of schema S in database connection D. ^If S is NULL, 6209369950Scy** then the highest transaction state of any schema on database connection D 6210369950Scy** is returned. Transaction states are (in order of lowest to highest): 6211369950Scy** <ol> 6212369950Scy** <li value="0"> SQLITE_TXN_NONE 6213369950Scy** <li value="1"> SQLITE_TXN_READ 6214369950Scy** <li value="2"> SQLITE_TXN_WRITE 6215369950Scy** </ol> 6216369950Scy** ^If the S argument to sqlite3_txn_state(D,S) is not the name of 6217369950Scy** a valid schema, then -1 is returned. 6218369950Scy*/ 6219369950ScySQLITE_API int sqlite3_txn_state(sqlite3*,const char *zSchema); 6220369950Scy 6221369950Scy/* 6222369950Scy** CAPI3REF: Allowed return values from [sqlite3_txn_state()] 6223369950Scy** KEYWORDS: {transaction state} 6224369950Scy** 6225369950Scy** These constants define the current transaction state of a database file. 6226369950Scy** ^The [sqlite3_txn_state(D,S)] interface returns one of these 6227369950Scy** constants in order to describe the transaction state of schema S 6228369950Scy** in [database connection] D. 6229369950Scy** 6230369950Scy** <dl> 6231369950Scy** [[SQLITE_TXN_NONE]] <dt>SQLITE_TXN_NONE</dt> 6232369950Scy** <dd>The SQLITE_TXN_NONE state means that no transaction is currently 6233369950Scy** pending.</dd> 6234369950Scy** 6235369950Scy** [[SQLITE_TXN_READ]] <dt>SQLITE_TXN_READ</dt> 6236369950Scy** <dd>The SQLITE_TXN_READ state means that the database is currently 6237369950Scy** in a read transaction. Content has been read from the database file 6238369950Scy** but nothing in the database file has changed. The transaction state 6239369950Scy** will advanced to SQLITE_TXN_WRITE if any changes occur and there are 6240369950Scy** no other conflicting concurrent write transactions. The transaction 6241369950Scy** state will revert to SQLITE_TXN_NONE following a [ROLLBACK] or 6242369950Scy** [COMMIT].</dd> 6243369950Scy** 6244369950Scy** [[SQLITE_TXN_WRITE]] <dt>SQLITE_TXN_WRITE</dt> 6245369950Scy** <dd>The SQLITE_TXN_WRITE state means that the database is currently 6246369950Scy** in a write transaction. Content has been written to the database file 6247369950Scy** but has not yet committed. The transaction state will change to 6248369950Scy** to SQLITE_TXN_NONE at the next [ROLLBACK] or [COMMIT].</dd> 6249369950Scy*/ 6250369950Scy#define SQLITE_TXN_NONE 0 6251369950Scy#define SQLITE_TXN_READ 1 6252369950Scy#define SQLITE_TXN_WRITE 2 6253369950Scy 6254369950Scy/* 6255251883Speter** CAPI3REF: Find the next prepared statement 6256286510Speter** METHOD: sqlite3 6257251883Speter** 6258251883Speter** ^This interface returns a pointer to the next [prepared statement] after 6259251883Speter** pStmt associated with the [database connection] pDb. ^If pStmt is NULL 6260251883Speter** then this interface returns a pointer to the first prepared statement 6261251883Speter** associated with the database connection pDb. ^If no prepared statement 6262251883Speter** satisfies the conditions of this routine, it returns NULL. 6263251883Speter** 6264251883Speter** The [database connection] pointer D in a call to 6265251883Speter** [sqlite3_next_stmt(D,S)] must refer to an open database 6266251883Speter** connection and in particular must not be a NULL pointer. 6267251883Speter*/ 6268322444SpeterSQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); 6269251883Speter 6270251883Speter/* 6271251883Speter** CAPI3REF: Commit And Rollback Notification Callbacks 6272286510Speter** METHOD: sqlite3 6273251883Speter** 6274251883Speter** ^The sqlite3_commit_hook() interface registers a callback 6275251883Speter** function to be invoked whenever a transaction is [COMMIT | committed]. 6276251883Speter** ^Any callback set by a previous call to sqlite3_commit_hook() 6277251883Speter** for the same database connection is overridden. 6278251883Speter** ^The sqlite3_rollback_hook() interface registers a callback 6279251883Speter** function to be invoked whenever a transaction is [ROLLBACK | rolled back]. 6280251883Speter** ^Any callback set by a previous call to sqlite3_rollback_hook() 6281251883Speter** for the same database connection is overridden. 6282251883Speter** ^The pArg argument is passed through to the callback. 6283251883Speter** ^If the callback on a commit hook function returns non-zero, 6284251883Speter** then the commit is converted into a rollback. 6285251883Speter** 6286251883Speter** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions 6287251883Speter** return the P argument from the previous call of the same function 6288251883Speter** on the same [database connection] D, or NULL for 6289251883Speter** the first call for each function on D. 6290251883Speter** 6291251883Speter** The commit and rollback hook callbacks are not reentrant. 6292251883Speter** The callback implementation must not do anything that will modify 6293251883Speter** the database connection that invoked the callback. Any actions 6294251883Speter** to modify the database connection must be deferred until after the 6295251883Speter** completion of the [sqlite3_step()] call that triggered the commit 6296251883Speter** or rollback hook in the first place. 6297251883Speter** Note that running any other SQL statements, including SELECT statements, 6298251883Speter** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify 6299251883Speter** the database connections for the meaning of "modify" in this paragraph. 6300251883Speter** 6301251883Speter** ^Registering a NULL function disables the callback. 6302251883Speter** 6303251883Speter** ^When the commit hook callback routine returns zero, the [COMMIT] 6304251883Speter** operation is allowed to continue normally. ^If the commit hook 6305251883Speter** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK]. 6306251883Speter** ^The rollback hook is invoked on a rollback that results from a commit 6307251883Speter** hook returning non-zero, just as it would be with any other rollback. 6308251883Speter** 6309251883Speter** ^For the purposes of this API, a transaction is said to have been 6310251883Speter** rolled back if an explicit "ROLLBACK" statement is executed, or 6311251883Speter** an error or constraint causes an implicit rollback to occur. 6312251883Speter** ^The rollback callback is not invoked if a transaction is 6313251883Speter** automatically rolled back because the database connection is closed. 6314251883Speter** 6315251883Speter** See also the [sqlite3_update_hook()] interface. 6316251883Speter*/ 6317322444SpeterSQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); 6318322444SpeterSQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); 6319251883Speter 6320251883Speter/* 6321251883Speter** CAPI3REF: Data Change Notification Callbacks 6322286510Speter** METHOD: sqlite3 6323251883Speter** 6324251883Speter** ^The sqlite3_update_hook() interface registers a callback function 6325251883Speter** with the [database connection] identified by the first argument 6326269851Speter** to be invoked whenever a row is updated, inserted or deleted in 6327305002Scy** a [rowid table]. 6328251883Speter** ^Any callback set by a previous call to this function 6329251883Speter** for the same database connection is overridden. 6330251883Speter** 6331251883Speter** ^The second argument is a pointer to the function to invoke when a 6332269851Speter** row is updated, inserted or deleted in a rowid table. 6333251883Speter** ^The first argument to the callback is a copy of the third argument 6334251883Speter** to sqlite3_update_hook(). 6335251883Speter** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], 6336251883Speter** or [SQLITE_UPDATE], depending on the operation that caused the callback 6337251883Speter** to be invoked. 6338251883Speter** ^The third and fourth arguments to the callback contain pointers to the 6339251883Speter** database and table name containing the affected row. 6340251883Speter** ^The final callback parameter is the [rowid] of the row. 6341251883Speter** ^In the case of an update, this is the [rowid] after the update takes place. 6342251883Speter** 6343251883Speter** ^(The update hook is not invoked when internal system tables are 6344366076Scy** modified (i.e. sqlite_sequence).)^ 6345269851Speter** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified. 6346251883Speter** 6347251883Speter** ^In the current implementation, the update hook 6348322444Speter** is not invoked when conflicting rows are deleted because of an 6349251883Speter** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook 6350251883Speter** invoked when rows are deleted using the [truncate optimization]. 6351251883Speter** The exceptions defined in this paragraph might change in a future 6352251883Speter** release of SQLite. 6353251883Speter** 6354251883Speter** The update hook implementation must not do anything that will modify 6355251883Speter** the database connection that invoked the update hook. Any actions 6356251883Speter** to modify the database connection must be deferred until after the 6357251883Speter** completion of the [sqlite3_step()] call that triggered the update hook. 6358251883Speter** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 6359251883Speter** database connections for the meaning of "modify" in this paragraph. 6360251883Speter** 6361251883Speter** ^The sqlite3_update_hook(D,C,P) function 6362251883Speter** returns the P argument from the previous call 6363251883Speter** on the same [database connection] D, or NULL for 6364251883Speter** the first call on D. 6365251883Speter** 6366305002Scy** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()], 6367305002Scy** and [sqlite3_preupdate_hook()] interfaces. 6368251883Speter*/ 6369322444SpeterSQLITE_API void *sqlite3_update_hook( 6370366076Scy sqlite3*, 6371251883Speter void(*)(void *,int ,char const *,char const *,sqlite3_int64), 6372251883Speter void* 6373251883Speter); 6374251883Speter 6375251883Speter/* 6376251883Speter** CAPI3REF: Enable Or Disable Shared Pager Cache 6377251883Speter** 6378251883Speter** ^(This routine enables or disables the sharing of the database cache 6379251883Speter** and schema data structures between [database connection | connections] 6380251883Speter** to the same database. Sharing is enabled if the argument is true 6381251883Speter** and disabled if the argument is false.)^ 6382251883Speter** 6383251883Speter** ^Cache sharing is enabled and disabled for an entire process. 6384366076Scy** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]). 6385322444Speter** In prior versions of SQLite, 6386251883Speter** sharing was enabled or disabled for each thread separately. 6387251883Speter** 6388251883Speter** ^(The cache sharing mode set by this interface effects all subsequent 6389251883Speter** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. 6390361456Scy** Existing database connections continue to use the sharing mode 6391251883Speter** that was in effect at the time they were opened.)^ 6392251883Speter** 6393251883Speter** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled 6394251883Speter** successfully. An [error code] is returned otherwise.)^ 6395251883Speter** 6396361456Scy** ^Shared cache is disabled by default. It is recommended that it stay 6397361456Scy** that way. In other words, do not use this routine. This interface 6398361456Scy** continues to be provided for historical compatibility, but its use is 6399361456Scy** discouraged. Any use of shared cache is discouraged. If shared cache 6400361456Scy** must be used, it is recommended that shared cache only be enabled for 6401361456Scy** individual database connections using the [sqlite3_open_v2()] interface 6402361456Scy** with the [SQLITE_OPEN_SHAREDCACHE] flag. 6403251883Speter** 6404282328Sbapt** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0 6405366076Scy** and will always return SQLITE_MISUSE. On those systems, 6406366076Scy** shared cache mode should be enabled per-database connection via 6407282328Sbapt** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE]. 6408282328Sbapt** 6409251883Speter** This interface is threadsafe on processors where writing a 6410251883Speter** 32-bit integer is atomic. 6411251883Speter** 6412251883Speter** See Also: [SQLite Shared-Cache Mode] 6413251883Speter*/ 6414322444SpeterSQLITE_API int sqlite3_enable_shared_cache(int); 6415251883Speter 6416251883Speter/* 6417251883Speter** CAPI3REF: Attempt To Free Heap Memory 6418251883Speter** 6419251883Speter** ^The sqlite3_release_memory() interface attempts to free N bytes 6420251883Speter** of heap memory by deallocating non-essential memory allocations 6421251883Speter** held by the database library. Memory used to cache database 6422251883Speter** pages to improve performance is an example of non-essential memory. 6423251883Speter** ^sqlite3_release_memory() returns the number of bytes actually freed, 6424251883Speter** which might be more or less than the amount requested. 6425251883Speter** ^The sqlite3_release_memory() routine is a no-op returning zero 6426251883Speter** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT]. 6427251883Speter** 6428251883Speter** See also: [sqlite3_db_release_memory()] 6429251883Speter*/ 6430322444SpeterSQLITE_API int sqlite3_release_memory(int); 6431251883Speter 6432251883Speter/* 6433251883Speter** CAPI3REF: Free Memory Used By A Database Connection 6434286510Speter** METHOD: sqlite3 6435251883Speter** 6436251883Speter** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap 6437251883Speter** memory as possible from database connection D. Unlike the 6438269851Speter** [sqlite3_release_memory()] interface, this interface is in effect even 6439269851Speter** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is 6440251883Speter** omitted. 6441251883Speter** 6442251883Speter** See also: [sqlite3_release_memory()] 6443251883Speter*/ 6444322444SpeterSQLITE_API int sqlite3_db_release_memory(sqlite3*); 6445251883Speter 6446251883Speter/* 6447251883Speter** CAPI3REF: Impose A Limit On Heap Size 6448251883Speter** 6449361456Scy** These interfaces impose limits on the amount of heap memory that will be 6450361456Scy** by all database connections within a single process. 6451361456Scy** 6452251883Speter** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the 6453251883Speter** soft limit on the amount of heap memory that may be allocated by SQLite. 6454251883Speter** ^SQLite strives to keep heap memory utilization below the soft heap 6455251883Speter** limit by reducing the number of pages held in the page cache 6456251883Speter** as heap memory usages approaches the limit. 6457251883Speter** ^The soft heap limit is "soft" because even though SQLite strives to stay 6458251883Speter** below the limit, it will exceed the limit rather than generate 6459366076Scy** an [SQLITE_NOMEM] error. In other words, the soft heap limit 6460251883Speter** is advisory only. 6461251883Speter** 6462361456Scy** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of 6463361456Scy** N bytes on the amount of memory that will be allocated. ^The 6464361456Scy** sqlite3_hard_heap_limit64(N) interface is similar to 6465361456Scy** sqlite3_soft_heap_limit64(N) except that memory allocations will fail 6466361456Scy** when the hard heap limit is reached. 6467361456Scy** 6468361456Scy** ^The return value from both sqlite3_soft_heap_limit64() and 6469361456Scy** sqlite3_hard_heap_limit64() is the size of 6470361456Scy** the heap limit prior to the call, or negative in the case of an 6471251883Speter** error. ^If the argument N is negative 6472361456Scy** then no change is made to the heap limit. Hence, the current 6473361456Scy** size of heap limits can be determined by invoking 6474361456Scy** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1). 6475251883Speter** 6476361456Scy** ^Setting the heap limits to zero disables the heap limiter mechanism. 6477251883Speter** 6478361456Scy** ^The soft heap limit may not be greater than the hard heap limit. 6479361456Scy** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N) 6480361456Scy** is invoked with a value of N that is greater than the hard heap limit, 6481361456Scy** the the soft heap limit is set to the value of the hard heap limit. 6482361456Scy** ^The soft heap limit is automatically enabled whenever the hard heap 6483361456Scy** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and 6484361456Scy** the soft heap limit is outside the range of 1..N, then the soft heap 6485361456Scy** limit is set to N. ^Invoking sqlite3_soft_heap_limit64(0) when the 6486361456Scy** hard heap limit is enabled makes the soft heap limit equal to the 6487361456Scy** hard heap limit. 6488361456Scy** 6489361456Scy** The memory allocation limits can also be adjusted using 6490361456Scy** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit]. 6491361456Scy** 6492361456Scy** ^(The heap limits are not enforced in the current implementation 6493251883Speter** if one or more of following conditions are true: 6494251883Speter** 6495251883Speter** <ul> 6496361456Scy** <li> The limit value is set to zero. 6497251883Speter** <li> Memory accounting is disabled using a combination of the 6498251883Speter** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and 6499251883Speter** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option. 6500251883Speter** <li> An alternative page cache implementation is specified using 6501251883Speter** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...). 6502251883Speter** <li> The page cache allocates from its own memory pool supplied 6503251883Speter** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than 6504251883Speter** from the heap. 6505251883Speter** </ul>)^ 6506251883Speter** 6507361456Scy** The circumstances under which SQLite will enforce the heap limits may 6508251883Speter** changes in future releases of SQLite. 6509251883Speter*/ 6510322444SpeterSQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N); 6511361456ScySQLITE_API sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N); 6512251883Speter 6513251883Speter/* 6514251883Speter** CAPI3REF: Deprecated Soft Heap Limit Interface 6515251883Speter** DEPRECATED 6516251883Speter** 6517251883Speter** This is a deprecated version of the [sqlite3_soft_heap_limit64()] 6518251883Speter** interface. This routine is provided for historical compatibility 6519251883Speter** only. All new applications should use the 6520251883Speter** [sqlite3_soft_heap_limit64()] interface rather than this one. 6521251883Speter*/ 6522322444SpeterSQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N); 6523251883Speter 6524251883Speter 6525251883Speter/* 6526251883Speter** CAPI3REF: Extract Metadata About A Column Of A Table 6527286510Speter** METHOD: sqlite3 6528251883Speter** 6529282328Sbapt** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns 6530282328Sbapt** information about column C of table T in database D 6531282328Sbapt** on [database connection] X.)^ ^The sqlite3_table_column_metadata() 6532282328Sbapt** interface returns SQLITE_OK and fills in the non-NULL pointers in 6533282328Sbapt** the final five arguments with appropriate values if the specified 6534282328Sbapt** column exists. ^The sqlite3_table_column_metadata() interface returns 6535361456Scy** SQLITE_ERROR if the specified column does not exist. 6536282328Sbapt** ^If the column-name parameter to sqlite3_table_column_metadata() is a 6537305002Scy** NULL pointer, then this routine simply checks for the existence of the 6538282328Sbapt** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it 6539322444Speter** does not. If the table name parameter T in a call to 6540322444Speter** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is 6541322444Speter** undefined behavior. 6542251883Speter** 6543251883Speter** ^The column is identified by the second, third and fourth parameters to 6544282328Sbapt** this function. ^(The second parameter is either the name of the database 6545251883Speter** (i.e. "main", "temp", or an attached database) containing the specified 6546282328Sbapt** table or NULL.)^ ^If it is NULL, then all attached databases are searched 6547251883Speter** for the table using the same algorithm used by the database engine to 6548251883Speter** resolve unqualified table references. 6549251883Speter** 6550251883Speter** ^The third and fourth parameters to this function are the table and column 6551282328Sbapt** name of the desired column, respectively. 6552251883Speter** 6553251883Speter** ^Metadata is returned by writing to the memory locations passed as the 5th 6554251883Speter** and subsequent parameters to this function. ^Any of these arguments may be 6555251883Speter** NULL, in which case the corresponding element of metadata is omitted. 6556251883Speter** 6557251883Speter** ^(<blockquote> 6558251883Speter** <table border="1"> 6559251883Speter** <tr><th> Parameter <th> Output<br>Type <th> Description 6560251883Speter** 6561251883Speter** <tr><td> 5th <td> const char* <td> Data type 6562251883Speter** <tr><td> 6th <td> const char* <td> Name of default collation sequence 6563251883Speter** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint 6564251883Speter** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY 6565251883Speter** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT] 6566251883Speter** </table> 6567251883Speter** </blockquote>)^ 6568251883Speter** 6569251883Speter** ^The memory pointed to by the character pointers returned for the 6570282328Sbapt** declaration type and collation sequence is valid until the next 6571251883Speter** call to any SQLite API function. 6572251883Speter** 6573251883Speter** ^If the specified table is actually a view, an [error code] is returned. 6574251883Speter** 6575366076Scy** ^If the specified column is "rowid", "oid" or "_rowid_" and the table 6576282328Sbapt** is not a [WITHOUT ROWID] table and an 6577251883Speter** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output 6578251883Speter** parameters are set for the explicitly declared column. ^(If there is no 6579282328Sbapt** [INTEGER PRIMARY KEY] column, then the outputs 6580282328Sbapt** for the [rowid] are set as follows: 6581251883Speter** 6582251883Speter** <pre> 6583251883Speter** data type: "INTEGER" 6584251883Speter** collation sequence: "BINARY" 6585251883Speter** not null: 0 6586251883Speter** primary key: 1 6587251883Speter** auto increment: 0 6588251883Speter** </pre>)^ 6589251883Speter** 6590282328Sbapt** ^This function causes all database schemas to be read from disk and 6591282328Sbapt** parsed, if that has not already been done, and returns an error if 6592282328Sbapt** any errors are encountered while loading the schema. 6593251883Speter*/ 6594322444SpeterSQLITE_API int sqlite3_table_column_metadata( 6595251883Speter sqlite3 *db, /* Connection handle */ 6596251883Speter const char *zDbName, /* Database name or NULL */ 6597251883Speter const char *zTableName, /* Table name */ 6598251883Speter const char *zColumnName, /* Column name */ 6599251883Speter char const **pzDataType, /* OUTPUT: Declared data type */ 6600251883Speter char const **pzCollSeq, /* OUTPUT: Collation sequence name */ 6601251883Speter int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ 6602251883Speter int *pPrimaryKey, /* OUTPUT: True if column part of PK */ 6603251883Speter int *pAutoinc /* OUTPUT: True if column is auto-increment */ 6604251883Speter); 6605251883Speter 6606251883Speter/* 6607251883Speter** CAPI3REF: Load An Extension 6608286510Speter** METHOD: sqlite3 6609251883Speter** 6610251883Speter** ^This interface loads an SQLite extension library from the named file. 6611251883Speter** 6612251883Speter** ^The sqlite3_load_extension() interface attempts to load an 6613251883Speter** [SQLite extension] library contained in the file zFile. If 6614251883Speter** the file cannot be loaded directly, attempts are made to load 6615251883Speter** with various operating-system specific extensions added. 6616251883Speter** So for example, if "samplelib" cannot be loaded, then names like 6617251883Speter** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might 6618251883Speter** be tried also. 6619251883Speter** 6620251883Speter** ^The entry point is zProc. 6621251883Speter** ^(zProc may be 0, in which case SQLite will try to come up with an 6622251883Speter** entry point name on its own. It first tries "sqlite3_extension_init". 6623251883Speter** If that does not work, it constructs a name "sqlite3_X_init" where the 6624251883Speter** X is consists of the lower-case equivalent of all ASCII alphabetic 6625251883Speter** characters in the filename from the last "/" to the first following 6626251883Speter** "." and omitting any initial "lib".)^ 6627251883Speter** ^The sqlite3_load_extension() interface returns 6628251883Speter** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. 6629251883Speter** ^If an error occurs and pzErrMsg is not 0, then the 6630251883Speter** [sqlite3_load_extension()] interface shall attempt to 6631251883Speter** fill *pzErrMsg with error message text stored in memory 6632251883Speter** obtained from [sqlite3_malloc()]. The calling function 6633251883Speter** should free this memory by calling [sqlite3_free()]. 6634251883Speter** 6635251883Speter** ^Extension loading must be enabled using 6636305002Scy** [sqlite3_enable_load_extension()] or 6637305002Scy** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL) 6638305002Scy** prior to calling this API, 6639251883Speter** otherwise an error will be returned. 6640251883Speter** 6641366076Scy** <b>Security warning:</b> It is recommended that the 6642305002Scy** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this 6643305002Scy** interface. The use of the [sqlite3_enable_load_extension()] interface 6644305002Scy** should be avoided. This will keep the SQL function [load_extension()] 6645305002Scy** disabled and prevent SQL injections from giving attackers 6646305002Scy** access to extension loading capabilities. 6647305002Scy** 6648251883Speter** See also the [load_extension() SQL function]. 6649251883Speter*/ 6650322444SpeterSQLITE_API int sqlite3_load_extension( 6651251883Speter sqlite3 *db, /* Load the extension into this database connection */ 6652251883Speter const char *zFile, /* Name of the shared library containing extension */ 6653251883Speter const char *zProc, /* Entry point. Derived from zFile if 0 */ 6654251883Speter char **pzErrMsg /* Put error message here if not 0 */ 6655251883Speter); 6656251883Speter 6657251883Speter/* 6658251883Speter** CAPI3REF: Enable Or Disable Extension Loading 6659286510Speter** METHOD: sqlite3 6660251883Speter** 6661251883Speter** ^So as not to open security holes in older applications that are 6662251883Speter** unprepared to deal with [extension loading], and as a means of disabling 6663251883Speter** [extension loading] while evaluating user-entered SQL, the following API 6664251883Speter** is provided to turn the [sqlite3_load_extension()] mechanism on and off. 6665251883Speter** 6666251883Speter** ^Extension loading is off by default. 6667251883Speter** ^Call the sqlite3_enable_load_extension() routine with onoff==1 6668251883Speter** to turn extension loading on and call it with onoff==0 to turn 6669251883Speter** it back off again. 6670305002Scy** 6671305002Scy** ^This interface enables or disables both the C-API 6672305002Scy** [sqlite3_load_extension()] and the SQL function [load_extension()]. 6673305002Scy** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..) 6674305002Scy** to enable or disable only the C-API.)^ 6675305002Scy** 6676305002Scy** <b>Security warning:</b> It is recommended that extension loading 6677361456Scy** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method 6678305002Scy** rather than this interface, so the [load_extension()] SQL function 6679305002Scy** remains disabled. This will prevent SQL injections from giving attackers 6680305002Scy** access to extension loading capabilities. 6681251883Speter*/ 6682322444SpeterSQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff); 6683251883Speter 6684251883Speter/* 6685251883Speter** CAPI3REF: Automatically Load Statically Linked Extensions 6686251883Speter** 6687251883Speter** ^This interface causes the xEntryPoint() function to be invoked for 6688251883Speter** each new [database connection] that is created. The idea here is that 6689251883Speter** xEntryPoint() is the entry point for a statically linked [SQLite extension] 6690251883Speter** that is to be automatically loaded into all new database connections. 6691251883Speter** 6692251883Speter** ^(Even though the function prototype shows that xEntryPoint() takes 6693251883Speter** no arguments and returns void, SQLite invokes xEntryPoint() with three 6694305002Scy** arguments and expects an integer result as if the signature of the 6695251883Speter** entry point where as follows: 6696251883Speter** 6697251883Speter** <blockquote><pre> 6698251883Speter** int xEntryPoint( 6699251883Speter** sqlite3 *db, 6700251883Speter** const char **pzErrMsg, 6701251883Speter** const struct sqlite3_api_routines *pThunk 6702251883Speter** ); 6703251883Speter** </pre></blockquote>)^ 6704251883Speter** 6705251883Speter** If the xEntryPoint routine encounters an error, it should make *pzErrMsg 6706251883Speter** point to an appropriate error message (obtained from [sqlite3_mprintf()]) 6707251883Speter** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg 6708251883Speter** is NULL before calling the xEntryPoint(). ^SQLite will invoke 6709251883Speter** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any 6710251883Speter** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()], 6711251883Speter** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail. 6712251883Speter** 6713251883Speter** ^Calling sqlite3_auto_extension(X) with an entry point X that is already 6714251883Speter** on the list of automatic extensions is a harmless no-op. ^No entry point 6715251883Speter** will be called more than once for each database connection that is opened. 6716251883Speter** 6717269851Speter** See also: [sqlite3_reset_auto_extension()] 6718269851Speter** and [sqlite3_cancel_auto_extension()] 6719251883Speter*/ 6720322444SpeterSQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void)); 6721251883Speter 6722251883Speter/* 6723269851Speter** CAPI3REF: Cancel Automatic Extension Loading 6724269851Speter** 6725269851Speter** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the 6726269851Speter** initialization routine X that was registered using a prior call to 6727269851Speter** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)] 6728366076Scy** routine returns 1 if initialization routine X was successfully 6729269851Speter** unregistered and it returns 0 if X was not on the list of initialization 6730269851Speter** routines. 6731269851Speter*/ 6732322444SpeterSQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void)); 6733269851Speter 6734269851Speter/* 6735251883Speter** CAPI3REF: Reset Automatic Extension Loading 6736251883Speter** 6737251883Speter** ^This interface disables all automatic extensions previously 6738251883Speter** registered using [sqlite3_auto_extension()]. 6739251883Speter*/ 6740322444SpeterSQLITE_API void sqlite3_reset_auto_extension(void); 6741251883Speter 6742251883Speter/* 6743251883Speter** The interface to the virtual-table mechanism is currently considered 6744251883Speter** to be experimental. The interface might change in incompatible ways. 6745251883Speter** If this is a problem for you, do not use the interface at this time. 6746251883Speter** 6747251883Speter** When the virtual-table mechanism stabilizes, we will declare the 6748251883Speter** interface fixed, support it indefinitely, and remove this comment. 6749251883Speter*/ 6750251883Speter 6751251883Speter/* 6752251883Speter** Structures used by the virtual table interface 6753251883Speter*/ 6754251883Spetertypedef struct sqlite3_vtab sqlite3_vtab; 6755251883Spetertypedef struct sqlite3_index_info sqlite3_index_info; 6756251883Spetertypedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; 6757251883Spetertypedef struct sqlite3_module sqlite3_module; 6758251883Speter 6759251883Speter/* 6760251883Speter** CAPI3REF: Virtual Table Object 6761251883Speter** KEYWORDS: sqlite3_module {virtual table module} 6762251883Speter** 6763366076Scy** This structure, sometimes called a "virtual table module", 6764366076Scy** defines the implementation of a [virtual table]. 6765251883Speter** This structure consists mostly of methods for the module. 6766251883Speter** 6767251883Speter** ^A virtual table module is created by filling in a persistent 6768251883Speter** instance of this structure and passing a pointer to that instance 6769251883Speter** to [sqlite3_create_module()] or [sqlite3_create_module_v2()]. 6770251883Speter** ^The registration remains valid until it is replaced by a different 6771251883Speter** module or until the [database connection] closes. The content 6772251883Speter** of this structure must not change while it is registered with 6773251883Speter** any database connection. 6774251883Speter*/ 6775251883Speterstruct sqlite3_module { 6776251883Speter int iVersion; 6777251883Speter int (*xCreate)(sqlite3*, void *pAux, 6778251883Speter int argc, const char *const*argv, 6779251883Speter sqlite3_vtab **ppVTab, char**); 6780251883Speter int (*xConnect)(sqlite3*, void *pAux, 6781251883Speter int argc, const char *const*argv, 6782251883Speter sqlite3_vtab **ppVTab, char**); 6783251883Speter int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); 6784251883Speter int (*xDisconnect)(sqlite3_vtab *pVTab); 6785251883Speter int (*xDestroy)(sqlite3_vtab *pVTab); 6786251883Speter int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); 6787251883Speter int (*xClose)(sqlite3_vtab_cursor*); 6788251883Speter int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, 6789251883Speter int argc, sqlite3_value **argv); 6790251883Speter int (*xNext)(sqlite3_vtab_cursor*); 6791251883Speter int (*xEof)(sqlite3_vtab_cursor*); 6792251883Speter int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); 6793251883Speter int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); 6794251883Speter int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); 6795251883Speter int (*xBegin)(sqlite3_vtab *pVTab); 6796251883Speter int (*xSync)(sqlite3_vtab *pVTab); 6797251883Speter int (*xCommit)(sqlite3_vtab *pVTab); 6798251883Speter int (*xRollback)(sqlite3_vtab *pVTab); 6799251883Speter int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, 6800251883Speter void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), 6801251883Speter void **ppArg); 6802251883Speter int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); 6803366076Scy /* The methods above are in version 1 of the sqlite_module object. Those 6804251883Speter ** below are for version 2 and greater. */ 6805251883Speter int (*xSavepoint)(sqlite3_vtab *pVTab, int); 6806251883Speter int (*xRelease)(sqlite3_vtab *pVTab, int); 6807251883Speter int (*xRollbackTo)(sqlite3_vtab *pVTab, int); 6808342292Scy /* The methods above are in versions 1 and 2 of the sqlite_module object. 6809342292Scy ** Those below are for version 3 and greater. */ 6810342292Scy int (*xShadowName)(const char*); 6811251883Speter}; 6812251883Speter 6813251883Speter/* 6814251883Speter** CAPI3REF: Virtual Table Indexing Information 6815251883Speter** KEYWORDS: sqlite3_index_info 6816251883Speter** 6817251883Speter** The sqlite3_index_info structure and its substructures is used as part 6818251883Speter** of the [virtual table] interface to 6819251883Speter** pass information into and receive the reply from the [xBestIndex] 6820251883Speter** method of a [virtual table module]. The fields under **Inputs** are the 6821251883Speter** inputs to xBestIndex and are read-only. xBestIndex inserts its 6822251883Speter** results into the **Outputs** fields. 6823251883Speter** 6824251883Speter** ^(The aConstraint[] array records WHERE clause constraints of the form: 6825251883Speter** 6826251883Speter** <blockquote>column OP expr</blockquote> 6827251883Speter** 6828251883Speter** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is 6829251883Speter** stored in aConstraint[].op using one of the 6830251883Speter** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^ 6831251883Speter** ^(The index of the column is stored in 6832251883Speter** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the 6833251883Speter** expr on the right-hand side can be evaluated (and thus the constraint 6834251883Speter** is usable) and false if it cannot.)^ 6835251883Speter** 6836251883Speter** ^The optimizer automatically inverts terms of the form "expr OP column" 6837251883Speter** and makes other simplifications to the WHERE clause in an attempt to 6838251883Speter** get as many WHERE clause terms into the form shown above as possible. 6839251883Speter** ^The aConstraint[] array only reports WHERE clause terms that are 6840251883Speter** relevant to the particular virtual table being queried. 6841251883Speter** 6842251883Speter** ^Information about the ORDER BY clause is stored in aOrderBy[]. 6843251883Speter** ^Each term of aOrderBy records a column of the ORDER BY clause. 6844251883Speter** 6845298161Sbapt** The colUsed field indicates which columns of the virtual table may be 6846298161Sbapt** required by the current scan. Virtual table columns are numbered from 6847298161Sbapt** zero in the order in which they appear within the CREATE TABLE statement 6848298161Sbapt** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62), 6849298161Sbapt** the corresponding bit is set within the colUsed mask if the column may be 6850298161Sbapt** required by SQLite. If the table has at least 64 columns and any column 6851298161Sbapt** to the right of the first 63 is required, then bit 63 of colUsed is also 6852298161Sbapt** set. In other words, column iCol may be required if the expression 6853366076Scy** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to 6854298161Sbapt** non-zero. 6855298161Sbapt** 6856251883Speter** The [xBestIndex] method must fill aConstraintUsage[] with information 6857251883Speter** about what parameters to pass to xFilter. ^If argvIndex>0 then 6858251883Speter** the right-hand side of the corresponding aConstraint[] is evaluated 6859251883Speter** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit 6860251883Speter** is true, then the constraint is assumed to be fully handled by the 6861361456Scy** virtual table and might not be checked again by the byte code.)^ ^(The 6862361456Scy** aConstraintUsage[].omit flag is an optimization hint. When the omit flag 6863361456Scy** is left in its default setting of false, the constraint will always be 6864361456Scy** checked separately in byte code. If the omit flag is change to true, then 6865361456Scy** the constraint may or may not be checked in byte code. In other words, 6866361456Scy** when the omit flag is true there is no guarantee that the constraint will 6867361456Scy** not be checked again using byte code.)^ 6868251883Speter** 6869251883Speter** ^The idxNum and idxPtr values are recorded and passed into the 6870251883Speter** [xFilter] method. 6871251883Speter** ^[sqlite3_free()] is used to free idxPtr if and only if 6872251883Speter** needToFreeIdxPtr is true. 6873251883Speter** 6874251883Speter** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in 6875251883Speter** the correct order to satisfy the ORDER BY clause so that no separate 6876251883Speter** sorting step is required. 6877251883Speter** 6878269851Speter** ^The estimatedCost value is an estimate of the cost of a particular 6879269851Speter** strategy. A cost of N indicates that the cost of the strategy is similar 6880366076Scy** to a linear scan of an SQLite table with N rows. A cost of log(N) 6881269851Speter** indicates that the expense of the operation is similar to that of a 6882269851Speter** binary search on a unique indexed field of an SQLite table with N rows. 6883269851Speter** 6884269851Speter** ^The estimatedRows value is an estimate of the number of rows that 6885269851Speter** will be returned by the strategy. 6886269851Speter** 6887366076Scy** The xBestIndex method may optionally populate the idxFlags field with a 6888298161Sbapt** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag - 6889298161Sbapt** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite 6890366076Scy** assumes that the strategy may visit at most one row. 6891298161Sbapt** 6892298161Sbapt** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then 6893298161Sbapt** SQLite also assumes that if a call to the xUpdate() method is made as 6894298161Sbapt** part of the same statement to delete or update a virtual table row and the 6895298161Sbapt** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback 6896298161Sbapt** any database changes. In other words, if the xUpdate() returns 6897298161Sbapt** SQLITE_CONSTRAINT, the database contents must be exactly as they were 6898298161Sbapt** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not 6899298161Sbapt** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by 6900298161Sbapt** the xUpdate method are automatically rolled back by SQLite. 6901298161Sbapt** 6902269851Speter** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info 6903366076Scy** structure for SQLite [version 3.8.2] ([dateof:3.8.2]). 6904322444Speter** If a virtual table extension is 6905366076Scy** used with an SQLite version earlier than 3.8.2, the results of attempting 6906366076Scy** to read or write the estimatedRows field are undefined (but are likely 6907361456Scy** to include crashing the application). The estimatedRows field should 6908269851Speter** therefore only be used if [sqlite3_libversion_number()] returns a 6909298161Sbapt** value greater than or equal to 3008002. Similarly, the idxFlags field 6910366076Scy** was added for [version 3.9.0] ([dateof:3.9.0]). 6911322444Speter** It may therefore only be used if 6912298161Sbapt** sqlite3_libversion_number() returns a value greater than or equal to 6913298161Sbapt** 3009000. 6914251883Speter*/ 6915251883Speterstruct sqlite3_index_info { 6916251883Speter /* Inputs */ 6917251883Speter int nConstraint; /* Number of entries in aConstraint */ 6918251883Speter struct sqlite3_index_constraint { 6919298161Sbapt int iColumn; /* Column constrained. -1 for ROWID */ 6920251883Speter unsigned char op; /* Constraint operator */ 6921251883Speter unsigned char usable; /* True if this constraint is usable */ 6922251883Speter int iTermOffset; /* Used internally - xBestIndex should ignore */ 6923251883Speter } *aConstraint; /* Table of WHERE clause constraints */ 6924251883Speter int nOrderBy; /* Number of terms in the ORDER BY clause */ 6925251883Speter struct sqlite3_index_orderby { 6926251883Speter int iColumn; /* Column number */ 6927251883Speter unsigned char desc; /* True for DESC. False for ASC. */ 6928251883Speter } *aOrderBy; /* The ORDER BY clause */ 6929251883Speter /* Outputs */ 6930251883Speter struct sqlite3_index_constraint_usage { 6931251883Speter int argvIndex; /* if >0, constraint is part of argv to xFilter */ 6932251883Speter unsigned char omit; /* Do not code a test for this constraint */ 6933251883Speter } *aConstraintUsage; 6934251883Speter int idxNum; /* Number used to identify the index */ 6935251883Speter char *idxStr; /* String, possibly obtained from sqlite3_malloc */ 6936251883Speter int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ 6937251883Speter int orderByConsumed; /* True if output is already ordered */ 6938269851Speter double estimatedCost; /* Estimated cost of using this index */ 6939269851Speter /* Fields below are only available in SQLite 3.8.2 and later */ 6940269851Speter sqlite3_int64 estimatedRows; /* Estimated number of rows returned */ 6941298161Sbapt /* Fields below are only available in SQLite 3.9.0 and later */ 6942298161Sbapt int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */ 6943298161Sbapt /* Fields below are only available in SQLite 3.10.0 and later */ 6944298161Sbapt sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */ 6945251883Speter}; 6946251883Speter 6947251883Speter/* 6948298161Sbapt** CAPI3REF: Virtual Table Scan Flags 6949342292Scy** 6950366076Scy** Virtual table implementations are allowed to set the 6951342292Scy** [sqlite3_index_info].idxFlags field to some combination of 6952342292Scy** these bits. 6953298161Sbapt*/ 6954298161Sbapt#define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */ 6955298161Sbapt 6956298161Sbapt/* 6957251883Speter** CAPI3REF: Virtual Table Constraint Operator Codes 6958251883Speter** 6959361456Scy** These macros define the allowed values for the 6960251883Speter** [sqlite3_index_info].aConstraint[].op field. Each value represents 6961251883Speter** an operator that is part of a constraint term in the wHERE clause of 6962251883Speter** a query that uses a [virtual table]. 6963251883Speter*/ 6964342292Scy#define SQLITE_INDEX_CONSTRAINT_EQ 2 6965342292Scy#define SQLITE_INDEX_CONSTRAINT_GT 4 6966342292Scy#define SQLITE_INDEX_CONSTRAINT_LE 8 6967342292Scy#define SQLITE_INDEX_CONSTRAINT_LT 16 6968342292Scy#define SQLITE_INDEX_CONSTRAINT_GE 32 6969342292Scy#define SQLITE_INDEX_CONSTRAINT_MATCH 64 6970342292Scy#define SQLITE_INDEX_CONSTRAINT_LIKE 65 6971342292Scy#define SQLITE_INDEX_CONSTRAINT_GLOB 66 6972342292Scy#define SQLITE_INDEX_CONSTRAINT_REGEXP 67 6973342292Scy#define SQLITE_INDEX_CONSTRAINT_NE 68 6974342292Scy#define SQLITE_INDEX_CONSTRAINT_ISNOT 69 6975342292Scy#define SQLITE_INDEX_CONSTRAINT_ISNOTNULL 70 6976342292Scy#define SQLITE_INDEX_CONSTRAINT_ISNULL 71 6977342292Scy#define SQLITE_INDEX_CONSTRAINT_IS 72 6978342292Scy#define SQLITE_INDEX_CONSTRAINT_FUNCTION 150 6979251883Speter 6980251883Speter/* 6981251883Speter** CAPI3REF: Register A Virtual Table Implementation 6982286510Speter** METHOD: sqlite3 6983251883Speter** 6984251883Speter** ^These routines are used to register a new [virtual table module] name. 6985251883Speter** ^Module names must be registered before 6986251883Speter** creating a new [virtual table] using the module and before using a 6987251883Speter** preexisting [virtual table] for the module. 6988251883Speter** 6989251883Speter** ^The module name is registered on the [database connection] specified 6990366076Scy** by the first parameter. ^The name of the module is given by the 6991251883Speter** second parameter. ^The third parameter is a pointer to 6992251883Speter** the implementation of the [virtual table module]. ^The fourth 6993251883Speter** parameter is an arbitrary client data pointer that is passed through 6994251883Speter** into the [xCreate] and [xConnect] methods of the virtual table module 6995251883Speter** when a new virtual table is be being created or reinitialized. 6996251883Speter** 6997251883Speter** ^The sqlite3_create_module_v2() interface has a fifth parameter which 6998251883Speter** is a pointer to a destructor for the pClientData. ^SQLite will 6999251883Speter** invoke the destructor function (if it is not NULL) when SQLite 7000251883Speter** no longer needs the pClientData pointer. ^The destructor will also 7001251883Speter** be invoked if the call to sqlite3_create_module_v2() fails. 7002251883Speter** ^The sqlite3_create_module() 7003251883Speter** interface is equivalent to sqlite3_create_module_v2() with a NULL 7004251883Speter** destructor. 7005355326Scy** 7006355326Scy** ^If the third parameter (the pointer to the sqlite3_module object) is 7007355326Scy** NULL then no new module is create and any existing modules with the 7008355326Scy** same name are dropped. 7009355326Scy** 7010355326Scy** See also: [sqlite3_drop_modules()] 7011251883Speter*/ 7012322444SpeterSQLITE_API int sqlite3_create_module( 7013251883Speter sqlite3 *db, /* SQLite connection to register module with */ 7014251883Speter const char *zName, /* Name of the module */ 7015251883Speter const sqlite3_module *p, /* Methods for the module */ 7016251883Speter void *pClientData /* Client data for xCreate/xConnect */ 7017251883Speter); 7018322444SpeterSQLITE_API int sqlite3_create_module_v2( 7019251883Speter sqlite3 *db, /* SQLite connection to register module with */ 7020251883Speter const char *zName, /* Name of the module */ 7021251883Speter const sqlite3_module *p, /* Methods for the module */ 7022251883Speter void *pClientData, /* Client data for xCreate/xConnect */ 7023251883Speter void(*xDestroy)(void*) /* Module destructor function */ 7024251883Speter); 7025251883Speter 7026251883Speter/* 7027355326Scy** CAPI3REF: Remove Unnecessary Virtual Table Implementations 7028355326Scy** METHOD: sqlite3 7029355326Scy** 7030355326Scy** ^The sqlite3_drop_modules(D,L) interface removes all virtual 7031355326Scy** table modules from database connection D except those named on list L. 7032355326Scy** The L parameter must be either NULL or a pointer to an array of pointers 7033355326Scy** to strings where the array is terminated by a single NULL pointer. 7034355326Scy** ^If the L parameter is NULL, then all virtual table modules are removed. 7035355326Scy** 7036355326Scy** See also: [sqlite3_create_module()] 7037355326Scy*/ 7038355326ScySQLITE_API int sqlite3_drop_modules( 7039355326Scy sqlite3 *db, /* Remove modules from this connection */ 7040355326Scy const char **azKeep /* Except, do not remove the ones named here */ 7041355326Scy); 7042355326Scy 7043355326Scy/* 7044251883Speter** CAPI3REF: Virtual Table Instance Object 7045251883Speter** KEYWORDS: sqlite3_vtab 7046251883Speter** 7047251883Speter** Every [virtual table module] implementation uses a subclass 7048251883Speter** of this object to describe a particular instance 7049251883Speter** of the [virtual table]. Each subclass will 7050251883Speter** be tailored to the specific needs of the module implementation. 7051251883Speter** The purpose of this superclass is to define certain fields that are 7052251883Speter** common to all module implementations. 7053251883Speter** 7054251883Speter** ^Virtual tables methods can set an error message by assigning a 7055251883Speter** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should 7056251883Speter** take care that any prior string is freed by a call to [sqlite3_free()] 7057251883Speter** prior to assigning a new string to zErrMsg. ^After the error message 7058251883Speter** is delivered up to the client application, the string will be automatically 7059251883Speter** freed by sqlite3_free() and the zErrMsg field will be zeroed. 7060251883Speter*/ 7061251883Speterstruct sqlite3_vtab { 7062251883Speter const sqlite3_module *pModule; /* The module for this virtual table */ 7063282328Sbapt int nRef; /* Number of open cursors */ 7064251883Speter char *zErrMsg; /* Error message from sqlite3_mprintf() */ 7065251883Speter /* Virtual table implementations will typically add additional fields */ 7066251883Speter}; 7067251883Speter 7068251883Speter/* 7069251883Speter** CAPI3REF: Virtual Table Cursor Object 7070251883Speter** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor} 7071251883Speter** 7072251883Speter** Every [virtual table module] implementation uses a subclass of the 7073251883Speter** following structure to describe cursors that point into the 7074251883Speter** [virtual table] and are used 7075251883Speter** to loop through the virtual table. Cursors are created using the 7076251883Speter** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed 7077251883Speter** by the [sqlite3_module.xClose | xClose] method. Cursors are used 7078251883Speter** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods 7079251883Speter** of the module. Each module implementation will define 7080251883Speter** the content of a cursor structure to suit its own needs. 7081251883Speter** 7082251883Speter** This superclass exists in order to define fields of the cursor that 7083251883Speter** are common to all implementations. 7084251883Speter*/ 7085251883Speterstruct sqlite3_vtab_cursor { 7086251883Speter sqlite3_vtab *pVtab; /* Virtual table of this cursor */ 7087251883Speter /* Virtual table implementations will typically add additional fields */ 7088251883Speter}; 7089251883Speter 7090251883Speter/* 7091251883Speter** CAPI3REF: Declare The Schema Of A Virtual Table 7092251883Speter** 7093251883Speter** ^The [xCreate] and [xConnect] methods of a 7094251883Speter** [virtual table module] call this interface 7095251883Speter** to declare the format (the names and datatypes of the columns) of 7096251883Speter** the virtual tables they implement. 7097251883Speter*/ 7098322444SpeterSQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL); 7099251883Speter 7100251883Speter/* 7101251883Speter** CAPI3REF: Overload A Function For A Virtual Table 7102286510Speter** METHOD: sqlite3 7103251883Speter** 7104251883Speter** ^(Virtual tables can provide alternative implementations of functions 7105366076Scy** using the [xFindFunction] method of the [virtual table module]. 7106251883Speter** But global versions of those functions 7107251883Speter** must exist in order to be overloaded.)^ 7108251883Speter** 7109251883Speter** ^(This API makes sure a global version of a function with a particular 7110251883Speter** name and number of parameters exists. If no such function exists 7111251883Speter** before this API is called, a new function is created.)^ ^The implementation 7112251883Speter** of the new function always causes an exception to be thrown. So 7113251883Speter** the new function is not good for anything by itself. Its only 7114251883Speter** purpose is to be a placeholder function that can be overloaded 7115251883Speter** by a [virtual table]. 7116251883Speter*/ 7117322444SpeterSQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); 7118251883Speter 7119251883Speter/* 7120251883Speter** The interface to the virtual-table mechanism defined above (back up 7121251883Speter** to a comment remarkably similar to this one) is currently considered 7122251883Speter** to be experimental. The interface might change in incompatible ways. 7123251883Speter** If this is a problem for you, do not use the interface at this time. 7124251883Speter** 7125251883Speter** When the virtual-table mechanism stabilizes, we will declare the 7126251883Speter** interface fixed, support it indefinitely, and remove this comment. 7127251883Speter*/ 7128251883Speter 7129251883Speter/* 7130251883Speter** CAPI3REF: A Handle To An Open BLOB 7131251883Speter** KEYWORDS: {BLOB handle} {BLOB handles} 7132251883Speter** 7133251883Speter** An instance of this object represents an open BLOB on which 7134251883Speter** [sqlite3_blob_open | incremental BLOB I/O] can be performed. 7135251883Speter** ^Objects of this type are created by [sqlite3_blob_open()] 7136251883Speter** and destroyed by [sqlite3_blob_close()]. 7137251883Speter** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces 7138251883Speter** can be used to read or write small subsections of the BLOB. 7139251883Speter** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. 7140251883Speter*/ 7141251883Spetertypedef struct sqlite3_blob sqlite3_blob; 7142251883Speter 7143251883Speter/* 7144251883Speter** CAPI3REF: Open A BLOB For Incremental I/O 7145286510Speter** METHOD: sqlite3 7146286510Speter** CONSTRUCTOR: sqlite3_blob 7147251883Speter** 7148251883Speter** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located 7149251883Speter** in row iRow, column zColumn, table zTable in database zDb; 7150251883Speter** in other words, the same BLOB that would be selected by: 7151251883Speter** 7152251883Speter** <pre> 7153251883Speter** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow; 7154251883Speter** </pre>)^ 7155251883Speter** 7156366076Scy** ^(Parameter zDb is not the filename that contains the database, but 7157282328Sbapt** rather the symbolic name of the database. For attached databases, this is 7158282328Sbapt** the name that appears after the AS keyword in the [ATTACH] statement. 7159282328Sbapt** For the main database file, the database name is "main". For TEMP 7160282328Sbapt** tables, the database name is "temp".)^ 7161282328Sbapt** 7162251883Speter** ^If the flags parameter is non-zero, then the BLOB is opened for read 7163282328Sbapt** and write access. ^If the flags parameter is zero, the BLOB is opened for 7164282328Sbapt** read-only access. 7165251883Speter** 7166282328Sbapt** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored 7167282328Sbapt** in *ppBlob. Otherwise an [error code] is returned and, unless the error 7168282328Sbapt** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided 7169366076Scy** the API is not misused, it is always safe to call [sqlite3_blob_close()] 7170282328Sbapt** on *ppBlob after this function it returns. 7171251883Speter** 7172282328Sbapt** This function fails with SQLITE_ERROR if any of the following are true: 7173282328Sbapt** <ul> 7174366076Scy** <li> ^(Database zDb does not exist)^, 7175366076Scy** <li> ^(Table zTable does not exist within database zDb)^, 7176366076Scy** <li> ^(Table zTable is a WITHOUT ROWID table)^, 7177282328Sbapt** <li> ^(Column zColumn does not exist)^, 7178282328Sbapt** <li> ^(Row iRow is not present in the table)^, 7179282328Sbapt** <li> ^(The specified column of row iRow contains a value that is not 7180282328Sbapt** a TEXT or BLOB value)^, 7181366076Scy** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE 7182282328Sbapt** constraint and the blob is being opened for read/write access)^, 7183366076Scy** <li> ^([foreign key constraints | Foreign key constraints] are enabled, 7184282328Sbapt** column zColumn is part of a [child key] definition and the blob is 7185282328Sbapt** being opened for read/write access)^. 7186282328Sbapt** </ul> 7187251883Speter** 7188366076Scy** ^Unless it returns SQLITE_MISUSE, this function sets the 7189366076Scy** [database connection] error code and message accessible via 7190366076Scy** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 7191282328Sbapt** 7192322444Speter** A BLOB referenced by sqlite3_blob_open() may be read using the 7193322444Speter** [sqlite3_blob_read()] interface and modified by using 7194322444Speter** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a 7195322444Speter** different row of the same table using the [sqlite3_blob_reopen()] 7196322444Speter** interface. However, the column, table, or database of a [BLOB handle] 7197322444Speter** cannot be changed after the [BLOB handle] is opened. 7198282328Sbapt** 7199251883Speter** ^(If the row that a BLOB handle points to is modified by an 7200251883Speter** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects 7201251883Speter** then the BLOB handle is marked as "expired". 7202251883Speter** This is true if any column of the row is changed, even a column 7203251883Speter** other than the one the BLOB handle is open on.)^ 7204251883Speter** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for 7205251883Speter** an expired BLOB handle fail with a return code of [SQLITE_ABORT]. 7206251883Speter** ^(Changes written into a BLOB prior to the BLOB expiring are not 7207251883Speter** rolled back by the expiration of the BLOB. Such changes will eventually 7208251883Speter** commit if the transaction continues to completion.)^ 7209251883Speter** 7210251883Speter** ^Use the [sqlite3_blob_bytes()] interface to determine the size of 7211251883Speter** the opened blob. ^The size of a blob may not be changed by this 7212251883Speter** interface. Use the [UPDATE] SQL command to change the size of a 7213251883Speter** blob. 7214251883Speter** 7215251883Speter** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces 7216366076Scy** and the built-in [zeroblob] SQL function may be used to create a 7217282328Sbapt** zero-filled blob to read or write using the incremental-blob interface. 7218251883Speter** 7219251883Speter** To avoid a resource leak, every open [BLOB handle] should eventually 7220251883Speter** be released by a call to [sqlite3_blob_close()]. 7221322444Speter** 7222322444Speter** See also: [sqlite3_blob_close()], 7223322444Speter** [sqlite3_blob_reopen()], [sqlite3_blob_read()], 7224322444Speter** [sqlite3_blob_bytes()], [sqlite3_blob_write()]. 7225251883Speter*/ 7226322444SpeterSQLITE_API int sqlite3_blob_open( 7227251883Speter sqlite3*, 7228251883Speter const char *zDb, 7229251883Speter const char *zTable, 7230251883Speter const char *zColumn, 7231251883Speter sqlite3_int64 iRow, 7232251883Speter int flags, 7233251883Speter sqlite3_blob **ppBlob 7234251883Speter); 7235251883Speter 7236251883Speter/* 7237251883Speter** CAPI3REF: Move a BLOB Handle to a New Row 7238286510Speter** METHOD: sqlite3_blob 7239251883Speter** 7240322444Speter** ^This function is used to move an existing [BLOB handle] so that it points 7241251883Speter** to a different row of the same database table. ^The new row is identified 7242251883Speter** by the rowid value passed as the second argument. Only the row can be 7243251883Speter** changed. ^The database, table and column on which the blob handle is open 7244322444Speter** remain the same. Moving an existing [BLOB handle] to a new row is 7245251883Speter** faster than closing the existing handle and opening a new one. 7246251883Speter** 7247251883Speter** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] - 7248251883Speter** it must exist and there must be either a blob or text value stored in 7249251883Speter** the nominated column.)^ ^If the new row is not present in the table, or if 7250251883Speter** it does not contain a blob or text value, or if another error occurs, an 7251251883Speter** SQLite error code is returned and the blob handle is considered aborted. 7252251883Speter** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or 7253251883Speter** [sqlite3_blob_reopen()] on an aborted blob handle immediately return 7254251883Speter** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle 7255251883Speter** always returns zero. 7256251883Speter** 7257251883Speter** ^This function sets the database handle error code and message. 7258251883Speter*/ 7259322444SpeterSQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64); 7260251883Speter 7261251883Speter/* 7262251883Speter** CAPI3REF: Close A BLOB Handle 7263286510Speter** DESTRUCTOR: sqlite3_blob 7264251883Speter** 7265282328Sbapt** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed 7266366076Scy** unconditionally. Even if this routine returns an error code, the 7267282328Sbapt** handle is still closed.)^ 7268251883Speter** 7269282328Sbapt** ^If the blob handle being closed was opened for read-write access, and if 7270282328Sbapt** the database is in auto-commit mode and there are no other open read-write 7271282328Sbapt** blob handles or active write statements, the current transaction is 7272282328Sbapt** committed. ^If an error occurs while committing the transaction, an error 7273282328Sbapt** code is returned and the transaction rolled back. 7274251883Speter** 7275282328Sbapt** Calling this function with an argument that is not a NULL pointer or an 7276366076Scy** open blob handle results in undefined behaviour. ^Calling this routine 7277366076Scy** with a null pointer (such as would be returned by a failed call to 7278282328Sbapt** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function 7279366076Scy** is passed a valid open blob handle, the values returned by the 7280282328Sbapt** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning. 7281251883Speter*/ 7282322444SpeterSQLITE_API int sqlite3_blob_close(sqlite3_blob *); 7283251883Speter 7284251883Speter/* 7285251883Speter** CAPI3REF: Return The Size Of An Open BLOB 7286286510Speter** METHOD: sqlite3_blob 7287251883Speter** 7288366076Scy** ^Returns the size in bytes of the BLOB accessible via the 7289251883Speter** successfully opened [BLOB handle] in its only argument. ^The 7290251883Speter** incremental blob I/O routines can only read or overwriting existing 7291251883Speter** blob content; they cannot change the size of a blob. 7292251883Speter** 7293251883Speter** This routine only works on a [BLOB handle] which has been created 7294251883Speter** by a prior successful call to [sqlite3_blob_open()] and which has not 7295251883Speter** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7296251883Speter** to this routine results in undefined and probably undesirable behavior. 7297251883Speter*/ 7298322444SpeterSQLITE_API int sqlite3_blob_bytes(sqlite3_blob *); 7299251883Speter 7300251883Speter/* 7301251883Speter** CAPI3REF: Read Data From A BLOB Incrementally 7302286510Speter** METHOD: sqlite3_blob 7303251883Speter** 7304251883Speter** ^(This function is used to read data from an open [BLOB handle] into a 7305251883Speter** caller-supplied buffer. N bytes of data are copied into buffer Z 7306251883Speter** from the open BLOB, starting at offset iOffset.)^ 7307251883Speter** 7308251883Speter** ^If offset iOffset is less than N bytes from the end of the BLOB, 7309251883Speter** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is 7310251883Speter** less than zero, [SQLITE_ERROR] is returned and no data is read. 7311251883Speter** ^The size of the blob (and hence the maximum value of N+iOffset) 7312251883Speter** can be determined using the [sqlite3_blob_bytes()] interface. 7313251883Speter** 7314251883Speter** ^An attempt to read from an expired [BLOB handle] fails with an 7315251883Speter** error code of [SQLITE_ABORT]. 7316251883Speter** 7317251883Speter** ^(On success, sqlite3_blob_read() returns SQLITE_OK. 7318251883Speter** Otherwise, an [error code] or an [extended error code] is returned.)^ 7319251883Speter** 7320251883Speter** This routine only works on a [BLOB handle] which has been created 7321251883Speter** by a prior successful call to [sqlite3_blob_open()] and which has not 7322251883Speter** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7323251883Speter** to this routine results in undefined and probably undesirable behavior. 7324251883Speter** 7325251883Speter** See also: [sqlite3_blob_write()]. 7326251883Speter*/ 7327322444SpeterSQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); 7328251883Speter 7329251883Speter/* 7330251883Speter** CAPI3REF: Write Data Into A BLOB Incrementally 7331286510Speter** METHOD: sqlite3_blob 7332251883Speter** 7333282328Sbapt** ^(This function is used to write data into an open [BLOB handle] from a 7334282328Sbapt** caller-supplied buffer. N bytes of data are copied from the buffer Z 7335282328Sbapt** into the open BLOB, starting at offset iOffset.)^ 7336251883Speter** 7337282328Sbapt** ^(On success, sqlite3_blob_write() returns SQLITE_OK. 7338282328Sbapt** Otherwise, an [error code] or an [extended error code] is returned.)^ 7339366076Scy** ^Unless SQLITE_MISUSE is returned, this function sets the 7340366076Scy** [database connection] error code and message accessible via 7341366076Scy** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 7342282328Sbapt** 7343251883Speter** ^If the [BLOB handle] passed as the first argument was not opened for 7344251883Speter** writing (the flags parameter to [sqlite3_blob_open()] was zero), 7345251883Speter** this function returns [SQLITE_READONLY]. 7346251883Speter** 7347282328Sbapt** This function may only modify the contents of the BLOB; it is 7348251883Speter** not possible to increase the size of a BLOB using this API. 7349251883Speter** ^If offset iOffset is less than N bytes from the end of the BLOB, 7350366076Scy** [SQLITE_ERROR] is returned and no data is written. The size of the 7351366076Scy** BLOB (and hence the maximum value of N+iOffset) can be determined 7352366076Scy** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less 7353282328Sbapt** than zero [SQLITE_ERROR] is returned and no data is written. 7354251883Speter** 7355251883Speter** ^An attempt to write to an expired [BLOB handle] fails with an 7356251883Speter** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred 7357251883Speter** before the [BLOB handle] expired are not rolled back by the 7358251883Speter** expiration of the handle, though of course those changes might 7359251883Speter** have been overwritten by the statement that expired the BLOB handle 7360251883Speter** or by other independent statements. 7361251883Speter** 7362251883Speter** This routine only works on a [BLOB handle] which has been created 7363251883Speter** by a prior successful call to [sqlite3_blob_open()] and which has not 7364251883Speter** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7365251883Speter** to this routine results in undefined and probably undesirable behavior. 7366251883Speter** 7367251883Speter** See also: [sqlite3_blob_read()]. 7368251883Speter*/ 7369322444SpeterSQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); 7370251883Speter 7371251883Speter/* 7372251883Speter** CAPI3REF: Virtual File System Objects 7373251883Speter** 7374251883Speter** A virtual filesystem (VFS) is an [sqlite3_vfs] object 7375251883Speter** that SQLite uses to interact 7376251883Speter** with the underlying operating system. Most SQLite builds come with a 7377251883Speter** single default VFS that is appropriate for the host computer. 7378251883Speter** New VFSes can be registered and existing VFSes can be unregistered. 7379251883Speter** The following interfaces are provided. 7380251883Speter** 7381251883Speter** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. 7382251883Speter** ^Names are case sensitive. 7383251883Speter** ^Names are zero-terminated UTF-8 strings. 7384251883Speter** ^If there is no match, a NULL pointer is returned. 7385251883Speter** ^If zVfsName is NULL then the default VFS is returned. 7386251883Speter** 7387251883Speter** ^New VFSes are registered with sqlite3_vfs_register(). 7388251883Speter** ^Each new VFS becomes the default VFS if the makeDflt flag is set. 7389251883Speter** ^The same VFS can be registered multiple times without injury. 7390251883Speter** ^To make an existing VFS into the default VFS, register it again 7391251883Speter** with the makeDflt flag set. If two different VFSes with the 7392251883Speter** same name are registered, the behavior is undefined. If a 7393251883Speter** VFS is registered with a name that is NULL or an empty string, 7394251883Speter** then the behavior is undefined. 7395251883Speter** 7396251883Speter** ^Unregister a VFS with the sqlite3_vfs_unregister() interface. 7397251883Speter** ^(If the default VFS is unregistered, another VFS is chosen as 7398251883Speter** the default. The choice for the new VFS is arbitrary.)^ 7399251883Speter*/ 7400322444SpeterSQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); 7401322444SpeterSQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); 7402322444SpeterSQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*); 7403251883Speter 7404251883Speter/* 7405251883Speter** CAPI3REF: Mutexes 7406251883Speter** 7407251883Speter** The SQLite core uses these routines for thread 7408251883Speter** synchronization. Though they are intended for internal 7409251883Speter** use by SQLite, code that links against SQLite is 7410251883Speter** permitted to use any of these routines. 7411251883Speter** 7412251883Speter** The SQLite source code contains multiple implementations 7413251883Speter** of these mutex routines. An appropriate implementation 7414282328Sbapt** is selected automatically at compile-time. The following 7415251883Speter** implementations are available in the SQLite core: 7416251883Speter** 7417251883Speter** <ul> 7418251883Speter** <li> SQLITE_MUTEX_PTHREADS 7419251883Speter** <li> SQLITE_MUTEX_W32 7420251883Speter** <li> SQLITE_MUTEX_NOOP 7421282328Sbapt** </ul> 7422251883Speter** 7423282328Sbapt** The SQLITE_MUTEX_NOOP implementation is a set of routines 7424251883Speter** that does no real locking and is appropriate for use in 7425282328Sbapt** a single-threaded application. The SQLITE_MUTEX_PTHREADS and 7426251883Speter** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix 7427251883Speter** and Windows. 7428251883Speter** 7429282328Sbapt** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor 7430251883Speter** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex 7431251883Speter** implementation is included with the library. In this case the 7432251883Speter** application must supply a custom mutex implementation using the 7433251883Speter** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function 7434251883Speter** before calling sqlite3_initialize() or any other public sqlite3_ 7435282328Sbapt** function that calls sqlite3_initialize(). 7436251883Speter** 7437251883Speter** ^The sqlite3_mutex_alloc() routine allocates a new 7438282328Sbapt** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc() 7439282328Sbapt** routine returns NULL if it is unable to allocate the requested 7440282328Sbapt** mutex. The argument to sqlite3_mutex_alloc() must one of these 7441282328Sbapt** integer constants: 7442251883Speter** 7443251883Speter** <ul> 7444251883Speter** <li> SQLITE_MUTEX_FAST 7445251883Speter** <li> SQLITE_MUTEX_RECURSIVE 7446366076Scy** <li> SQLITE_MUTEX_STATIC_MAIN 7447251883Speter** <li> SQLITE_MUTEX_STATIC_MEM 7448274884Sbapt** <li> SQLITE_MUTEX_STATIC_OPEN 7449251883Speter** <li> SQLITE_MUTEX_STATIC_PRNG 7450251883Speter** <li> SQLITE_MUTEX_STATIC_LRU 7451274884Sbapt** <li> SQLITE_MUTEX_STATIC_PMEM 7452274884Sbapt** <li> SQLITE_MUTEX_STATIC_APP1 7453274884Sbapt** <li> SQLITE_MUTEX_STATIC_APP2 7454282328Sbapt** <li> SQLITE_MUTEX_STATIC_APP3 7455298161Sbapt** <li> SQLITE_MUTEX_STATIC_VFS1 7456298161Sbapt** <li> SQLITE_MUTEX_STATIC_VFS2 7457298161Sbapt** <li> SQLITE_MUTEX_STATIC_VFS3 7458282328Sbapt** </ul> 7459251883Speter** 7460251883Speter** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) 7461251883Speter** cause sqlite3_mutex_alloc() to create 7462251883Speter** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE 7463251883Speter** is used but not necessarily so when SQLITE_MUTEX_FAST is used. 7464251883Speter** The mutex implementation does not need to make a distinction 7465251883Speter** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does 7466282328Sbapt** not want to. SQLite will only request a recursive mutex in 7467282328Sbapt** cases where it really needs one. If a faster non-recursive mutex 7468251883Speter** implementation is available on the host platform, the mutex subsystem 7469251883Speter** might return such a mutex in response to SQLITE_MUTEX_FAST. 7470251883Speter** 7471251883Speter** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other 7472251883Speter** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return 7473282328Sbapt** a pointer to a static preexisting mutex. ^Nine static mutexes are 7474251883Speter** used by the current version of SQLite. Future versions of SQLite 7475251883Speter** may add additional static mutexes. Static mutexes are for internal 7476251883Speter** use by SQLite only. Applications that use SQLite mutexes should 7477251883Speter** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or 7478251883Speter** SQLITE_MUTEX_RECURSIVE. 7479251883Speter** 7480251883Speter** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST 7481251883Speter** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() 7482282328Sbapt** returns a different mutex on every call. ^For the static 7483251883Speter** mutex types, the same mutex is returned on every call that has 7484251883Speter** the same type number. 7485251883Speter** 7486251883Speter** ^The sqlite3_mutex_free() routine deallocates a previously 7487282328Sbapt** allocated dynamic mutex. Attempting to deallocate a static 7488282328Sbapt** mutex results in undefined behavior. 7489251883Speter** 7490251883Speter** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt 7491251883Speter** to enter a mutex. ^If another thread is already within the mutex, 7492251883Speter** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return 7493251883Speter** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK] 7494251883Speter** upon successful entry. ^(Mutexes created using 7495251883Speter** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. 7496282328Sbapt** In such cases, the 7497251883Speter** mutex must be exited an equal number of times before another thread 7498282328Sbapt** can enter.)^ If the same thread tries to enter any mutex other 7499282328Sbapt** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined. 7500251883Speter** 7501251883Speter** ^(Some systems (for example, Windows 95) do not support the operation 7502251883Speter** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() 7503282328Sbapt** will always return SQLITE_BUSY. The SQLite core only ever uses 7504366076Scy** sqlite3_mutex_try() as an optimization so this is acceptable 7505282328Sbapt** behavior.)^ 7506251883Speter** 7507251883Speter** ^The sqlite3_mutex_leave() routine exits a mutex that was 7508282328Sbapt** previously entered by the same thread. The behavior 7509251883Speter** is undefined if the mutex is not currently entered by the 7510282328Sbapt** calling thread or is not currently allocated. 7511251883Speter** 7512251883Speter** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or 7513251883Speter** sqlite3_mutex_leave() is a NULL pointer, then all three routines 7514251883Speter** behave as no-ops. 7515251883Speter** 7516251883Speter** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. 7517251883Speter*/ 7518322444SpeterSQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int); 7519322444SpeterSQLITE_API void sqlite3_mutex_free(sqlite3_mutex*); 7520322444SpeterSQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*); 7521322444SpeterSQLITE_API int sqlite3_mutex_try(sqlite3_mutex*); 7522322444SpeterSQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*); 7523251883Speter 7524251883Speter/* 7525251883Speter** CAPI3REF: Mutex Methods Object 7526251883Speter** 7527251883Speter** An instance of this structure defines the low-level routines 7528251883Speter** used to allocate and use mutexes. 7529251883Speter** 7530251883Speter** Usually, the default mutex implementations provided by SQLite are 7531282328Sbapt** sufficient, however the application has the option of substituting a custom 7532251883Speter** implementation for specialized deployments or systems for which SQLite 7533282328Sbapt** does not provide a suitable implementation. In this case, the application 7534251883Speter** creates and populates an instance of this structure to pass 7535251883Speter** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. 7536251883Speter** Additionally, an instance of this structure can be used as an 7537251883Speter** output variable when querying the system for the current mutex 7538251883Speter** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. 7539251883Speter** 7540251883Speter** ^The xMutexInit method defined by this structure is invoked as 7541251883Speter** part of system initialization by the sqlite3_initialize() function. 7542251883Speter** ^The xMutexInit routine is called by SQLite exactly once for each 7543251883Speter** effective call to [sqlite3_initialize()]. 7544251883Speter** 7545251883Speter** ^The xMutexEnd method defined by this structure is invoked as 7546251883Speter** part of system shutdown by the sqlite3_shutdown() function. The 7547251883Speter** implementation of this method is expected to release all outstanding 7548251883Speter** resources obtained by the mutex methods implementation, especially 7549251883Speter** those obtained by the xMutexInit method. ^The xMutexEnd() 7550251883Speter** interface is invoked exactly once for each call to [sqlite3_shutdown()]. 7551251883Speter** 7552251883Speter** ^(The remaining seven methods defined by this structure (xMutexAlloc, 7553251883Speter** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and 7554251883Speter** xMutexNotheld) implement the following interfaces (respectively): 7555251883Speter** 7556251883Speter** <ul> 7557251883Speter** <li> [sqlite3_mutex_alloc()] </li> 7558251883Speter** <li> [sqlite3_mutex_free()] </li> 7559251883Speter** <li> [sqlite3_mutex_enter()] </li> 7560251883Speter** <li> [sqlite3_mutex_try()] </li> 7561251883Speter** <li> [sqlite3_mutex_leave()] </li> 7562251883Speter** <li> [sqlite3_mutex_held()] </li> 7563251883Speter** <li> [sqlite3_mutex_notheld()] </li> 7564251883Speter** </ul>)^ 7565251883Speter** 7566251883Speter** The only difference is that the public sqlite3_XXX functions enumerated 7567251883Speter** above silently ignore any invocations that pass a NULL pointer instead 7568251883Speter** of a valid mutex handle. The implementations of the methods defined 7569361456Scy** by this structure are not required to handle this case. The results 7570251883Speter** of passing a NULL pointer instead of a valid mutex handle are undefined 7571251883Speter** (i.e. it is acceptable to provide an implementation that segfaults if 7572251883Speter** it is passed a NULL pointer). 7573251883Speter** 7574282328Sbapt** The xMutexInit() method must be threadsafe. It must be harmless to 7575251883Speter** invoke xMutexInit() multiple times within the same process and without 7576251883Speter** intervening calls to xMutexEnd(). Second and subsequent calls to 7577251883Speter** xMutexInit() must be no-ops. 7578251883Speter** 7579282328Sbapt** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()] 7580282328Sbapt** and its associates). Similarly, xMutexAlloc() must not use SQLite memory 7581251883Speter** allocation for a static mutex. ^However xMutexAlloc() may use SQLite 7582251883Speter** memory allocation for a fast or recursive mutex. 7583251883Speter** 7584251883Speter** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is 7585251883Speter** called, but only if the prior call to xMutexInit returned SQLITE_OK. 7586251883Speter** If xMutexInit fails in any way, it is expected to clean up after itself 7587251883Speter** prior to returning. 7588251883Speter*/ 7589251883Spetertypedef struct sqlite3_mutex_methods sqlite3_mutex_methods; 7590251883Speterstruct sqlite3_mutex_methods { 7591251883Speter int (*xMutexInit)(void); 7592251883Speter int (*xMutexEnd)(void); 7593251883Speter sqlite3_mutex *(*xMutexAlloc)(int); 7594251883Speter void (*xMutexFree)(sqlite3_mutex *); 7595251883Speter void (*xMutexEnter)(sqlite3_mutex *); 7596251883Speter int (*xMutexTry)(sqlite3_mutex *); 7597251883Speter void (*xMutexLeave)(sqlite3_mutex *); 7598251883Speter int (*xMutexHeld)(sqlite3_mutex *); 7599251883Speter int (*xMutexNotheld)(sqlite3_mutex *); 7600251883Speter}; 7601251883Speter 7602251883Speter/* 7603251883Speter** CAPI3REF: Mutex Verification Routines 7604251883Speter** 7605251883Speter** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines 7606282328Sbapt** are intended for use inside assert() statements. The SQLite core 7607251883Speter** never uses these routines except inside an assert() and applications 7608282328Sbapt** are advised to follow the lead of the core. The SQLite core only 7609251883Speter** provides implementations for these routines when it is compiled 7610282328Sbapt** with the SQLITE_DEBUG flag. External mutex implementations 7611251883Speter** are only required to provide these routines if SQLITE_DEBUG is 7612251883Speter** defined and if NDEBUG is not defined. 7613251883Speter** 7614282328Sbapt** These routines should return true if the mutex in their argument 7615251883Speter** is held or not held, respectively, by the calling thread. 7616251883Speter** 7617282328Sbapt** The implementation is not required to provide versions of these 7618251883Speter** routines that actually work. If the implementation does not provide working 7619251883Speter** versions of these routines, it should at least provide stubs that always 7620251883Speter** return true so that one does not get spurious assertion failures. 7621251883Speter** 7622282328Sbapt** If the argument to sqlite3_mutex_held() is a NULL pointer then 7623251883Speter** the routine should return 1. This seems counter-intuitive since 7624251883Speter** clearly the mutex cannot be held if it does not exist. But 7625251883Speter** the reason the mutex does not exist is because the build is not 7626251883Speter** using mutexes. And we do not want the assert() containing the 7627251883Speter** call to sqlite3_mutex_held() to fail, so a non-zero return is 7628282328Sbapt** the appropriate thing to do. The sqlite3_mutex_notheld() 7629251883Speter** interface should also return 1 when given a NULL pointer. 7630251883Speter*/ 7631251883Speter#ifndef NDEBUG 7632322444SpeterSQLITE_API int sqlite3_mutex_held(sqlite3_mutex*); 7633322444SpeterSQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*); 7634251883Speter#endif 7635251883Speter 7636251883Speter/* 7637251883Speter** CAPI3REF: Mutex Types 7638251883Speter** 7639251883Speter** The [sqlite3_mutex_alloc()] interface takes a single argument 7640251883Speter** which is one of these integer constants. 7641251883Speter** 7642251883Speter** The set of static mutexes may change from one SQLite release to the 7643251883Speter** next. Applications that override the built-in mutex logic must be 7644251883Speter** prepared to accommodate additional static mutexes. 7645251883Speter*/ 7646251883Speter#define SQLITE_MUTEX_FAST 0 7647251883Speter#define SQLITE_MUTEX_RECURSIVE 1 7648366076Scy#define SQLITE_MUTEX_STATIC_MAIN 2 7649251883Speter#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ 7650251883Speter#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */ 7651251883Speter#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */ 7652322444Speter#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */ 7653251883Speter#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ 7654251883Speter#define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */ 7655251883Speter#define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */ 7656274884Sbapt#define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */ 7657274884Sbapt#define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */ 7658274884Sbapt#define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */ 7659286510Speter#define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */ 7660286510Speter#define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */ 7661286510Speter#define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */ 7662251883Speter 7663366076Scy/* Legacy compatibility: */ 7664366076Scy#define SQLITE_MUTEX_STATIC_MASTER 2 7665366076Scy 7666366076Scy 7667251883Speter/* 7668251883Speter** CAPI3REF: Retrieve the mutex for a database connection 7669286510Speter** METHOD: sqlite3 7670251883Speter** 7671366076Scy** ^This interface returns a pointer the [sqlite3_mutex] object that 7672251883Speter** serializes access to the [database connection] given in the argument 7673251883Speter** when the [threading mode] is Serialized. 7674251883Speter** ^If the [threading mode] is Single-thread or Multi-thread then this 7675251883Speter** routine returns a NULL pointer. 7676251883Speter*/ 7677322444SpeterSQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*); 7678251883Speter 7679251883Speter/* 7680251883Speter** CAPI3REF: Low-Level Control Of Database Files 7681286510Speter** METHOD: sqlite3 7682342292Scy** KEYWORDS: {file control} 7683251883Speter** 7684251883Speter** ^The [sqlite3_file_control()] interface makes a direct call to the 7685251883Speter** xFileControl method for the [sqlite3_io_methods] object associated 7686251883Speter** with a particular database identified by the second argument. ^The 7687251883Speter** name of the database is "main" for the main database or "temp" for the 7688251883Speter** TEMP database, or the name that appears after the AS keyword for 7689251883Speter** databases that are added using the [ATTACH] SQL command. 7690251883Speter** ^A NULL pointer can be used in place of "main" to refer to the 7691251883Speter** main database file. 7692251883Speter** ^The third and fourth parameters to this routine 7693251883Speter** are passed directly through to the second and third parameters of 7694251883Speter** the xFileControl method. ^The return value of the xFileControl 7695251883Speter** method becomes the return value of this routine. 7696251883Speter** 7697342292Scy** A few opcodes for [sqlite3_file_control()] are handled directly 7698366076Scy** by the SQLite core and never invoke the 7699342292Scy** sqlite3_io_methods.xFileControl method. 7700342292Scy** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes 7701251883Speter** a pointer to the underlying [sqlite3_file] object to be written into 7702342292Scy** the space pointed to by the 4th parameter. The 7703342292Scy** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns 7704342292Scy** the [sqlite3_file] object associated with the journal file instead of 7705342292Scy** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns 7706342292Scy** a pointer to the underlying [sqlite3_vfs] object for the file. 7707342292Scy** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter 7708342292Scy** from the pager. 7709251883Speter** 7710251883Speter** ^If the second parameter (zDbName) does not match the name of any 7711251883Speter** open database file, then SQLITE_ERROR is returned. ^This error 7712251883Speter** code is not remembered and will not be recalled by [sqlite3_errcode()] 7713251883Speter** or [sqlite3_errmsg()]. The underlying xFileControl method might 7714251883Speter** also return SQLITE_ERROR. There is no way to distinguish between 7715251883Speter** an incorrect zDbName and an SQLITE_ERROR return from the underlying 7716251883Speter** xFileControl method. 7717251883Speter** 7718342292Scy** See also: [file control opcodes] 7719251883Speter*/ 7720322444SpeterSQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); 7721251883Speter 7722251883Speter/* 7723251883Speter** CAPI3REF: Testing Interface 7724251883Speter** 7725251883Speter** ^The sqlite3_test_control() interface is used to read out internal 7726251883Speter** state of SQLite and to inject faults into SQLite for testing 7727251883Speter** purposes. ^The first parameter is an operation code that determines 7728251883Speter** the number, meaning, and operation of all subsequent parameters. 7729251883Speter** 7730251883Speter** This interface is not for use by applications. It exists solely 7731251883Speter** for verifying the correct operation of the SQLite library. Depending 7732251883Speter** on how the SQLite library is compiled, this interface might not exist. 7733251883Speter** 7734251883Speter** The details of the operation codes, their meanings, the parameters 7735251883Speter** they take, and what they do are all subject to change without notice. 7736251883Speter** Unlike most of the SQLite API, this function is not guaranteed to 7737251883Speter** operate consistently from one release to the next. 7738251883Speter*/ 7739322444SpeterSQLITE_API int sqlite3_test_control(int op, ...); 7740251883Speter 7741251883Speter/* 7742251883Speter** CAPI3REF: Testing Interface Operation Codes 7743251883Speter** 7744251883Speter** These constants are the valid operation code parameters used 7745251883Speter** as the first argument to [sqlite3_test_control()]. 7746251883Speter** 7747251883Speter** These parameters and their meanings are subject to change 7748251883Speter** without notice. These values are for testing purposes only. 7749251883Speter** Applications should not use any of these parameters or the 7750251883Speter** [sqlite3_test_control()] interface. 7751251883Speter*/ 7752251883Speter#define SQLITE_TESTCTRL_FIRST 5 7753251883Speter#define SQLITE_TESTCTRL_PRNG_SAVE 5 7754251883Speter#define SQLITE_TESTCTRL_PRNG_RESTORE 6 7755355326Scy#define SQLITE_TESTCTRL_PRNG_RESET 7 /* NOT USED */ 7756251883Speter#define SQLITE_TESTCTRL_BITVEC_TEST 8 7757251883Speter#define SQLITE_TESTCTRL_FAULT_INSTALL 9 7758251883Speter#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 7759251883Speter#define SQLITE_TESTCTRL_PENDING_BYTE 11 7760251883Speter#define SQLITE_TESTCTRL_ASSERT 12 7761251883Speter#define SQLITE_TESTCTRL_ALWAYS 13 7762362190Scy#define SQLITE_TESTCTRL_RESERVE 14 /* NOT USED */ 7763251883Speter#define SQLITE_TESTCTRL_OPTIMIZATIONS 15 7764342292Scy#define SQLITE_TESTCTRL_ISKEYWORD 16 /* NOT USED */ 7765342292Scy#define SQLITE_TESTCTRL_SCRATCHMALLOC 17 /* NOT USED */ 7766342292Scy#define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS 17 7767251883Speter#define SQLITE_TESTCTRL_LOCALTIME_FAULT 18 7768274884Sbapt#define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */ 7769322444Speter#define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19 7770269851Speter#define SQLITE_TESTCTRL_NEVER_CORRUPT 20 7771269851Speter#define SQLITE_TESTCTRL_VDBE_COVERAGE 21 7772269851Speter#define SQLITE_TESTCTRL_BYTEORDER 22 7773274884Sbapt#define SQLITE_TESTCTRL_ISINIT 23 7774274884Sbapt#define SQLITE_TESTCTRL_SORTER_MMAP 24 7775282328Sbapt#define SQLITE_TESTCTRL_IMPOSTER 25 7776342292Scy#define SQLITE_TESTCTRL_PARSER_COVERAGE 26 7777351633Scy#define SQLITE_TESTCTRL_RESULT_INTREAL 27 7778355326Scy#define SQLITE_TESTCTRL_PRNG_SEED 28 7779355326Scy#define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS 29 7780369950Scy#define SQLITE_TESTCTRL_SEEK_COUNT 30 7781369951Scy#define SQLITE_TESTCTRL_TRACEFLAGS 31 7782369951Scy#define SQLITE_TESTCTRL_LAST 31 /* Largest TESTCTRL */ 7783251883Speter 7784251883Speter/* 7785342292Scy** CAPI3REF: SQL Keyword Checking 7786342292Scy** 7787366076Scy** These routines provide access to the set of SQL language keywords 7788342292Scy** recognized by SQLite. Applications can uses these routines to determine 7789342292Scy** whether or not a specific identifier needs to be escaped (for example, 7790342292Scy** by enclosing in double-quotes) so as not to confuse the parser. 7791342292Scy** 7792342292Scy** The sqlite3_keyword_count() interface returns the number of distinct 7793342292Scy** keywords understood by SQLite. 7794342292Scy** 7795342292Scy** The sqlite3_keyword_name(N,Z,L) interface finds the N-th keyword and 7796342292Scy** makes *Z point to that keyword expressed as UTF8 and writes the number 7797342292Scy** of bytes in the keyword into *L. The string that *Z points to is not 7798342292Scy** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns 7799342292Scy** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z 7800342292Scy** or L are NULL or invalid pointers then calls to 7801342292Scy** sqlite3_keyword_name(N,Z,L) result in undefined behavior. 7802342292Scy** 7803342292Scy** The sqlite3_keyword_check(Z,L) interface checks to see whether or not 7804342292Scy** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero 7805342292Scy** if it is and zero if not. 7806342292Scy** 7807342292Scy** The parser used by SQLite is forgiving. It is often possible to use 7808342292Scy** a keyword as an identifier as long as such use does not result in a 7809342292Scy** parsing ambiguity. For example, the statement 7810342292Scy** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and 7811342292Scy** creates a new table named "BEGIN" with three columns named 7812342292Scy** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid 7813342292Scy** using keywords as identifiers. Common techniques used to avoid keyword 7814342292Scy** name collisions include: 7815342292Scy** <ul> 7816342292Scy** <li> Put all identifier names inside double-quotes. This is the official 7817342292Scy** SQL way to escape identifier names. 7818342292Scy** <li> Put identifier names inside [...]. This is not standard SQL, 7819342292Scy** but it is what SQL Server does and so lots of programmers use this 7820342292Scy** technique. 7821342292Scy** <li> Begin every identifier with the letter "Z" as no SQL keywords start 7822342292Scy** with "Z". 7823342292Scy** <li> Include a digit somewhere in every identifier name. 7824342292Scy** </ul> 7825342292Scy** 7826342292Scy** Note that the number of keywords understood by SQLite can depend on 7827342292Scy** compile-time options. For example, "VACUUM" is not a keyword if 7828342292Scy** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also, 7829342292Scy** new keywords may be added to future releases of SQLite. 7830342292Scy*/ 7831342292ScySQLITE_API int sqlite3_keyword_count(void); 7832342292ScySQLITE_API int sqlite3_keyword_name(int,const char**,int*); 7833342292ScySQLITE_API int sqlite3_keyword_check(const char*,int); 7834342292Scy 7835342292Scy/* 7836342292Scy** CAPI3REF: Dynamic String Object 7837342292Scy** KEYWORDS: {dynamic string} 7838342292Scy** 7839342292Scy** An instance of the sqlite3_str object contains a dynamically-sized 7840342292Scy** string under construction. 7841342292Scy** 7842342292Scy** The lifecycle of an sqlite3_str object is as follows: 7843342292Scy** <ol> 7844342292Scy** <li> ^The sqlite3_str object is created using [sqlite3_str_new()]. 7845342292Scy** <li> ^Text is appended to the sqlite3_str object using various 7846342292Scy** methods, such as [sqlite3_str_appendf()]. 7847342292Scy** <li> ^The sqlite3_str object is destroyed and the string it created 7848342292Scy** is returned using the [sqlite3_str_finish()] interface. 7849342292Scy** </ol> 7850342292Scy*/ 7851342292Scytypedef struct sqlite3_str sqlite3_str; 7852342292Scy 7853342292Scy/* 7854342292Scy** CAPI3REF: Create A New Dynamic String Object 7855342292Scy** CONSTRUCTOR: sqlite3_str 7856342292Scy** 7857342292Scy** ^The [sqlite3_str_new(D)] interface allocates and initializes 7858342292Scy** a new [sqlite3_str] object. To avoid memory leaks, the object returned by 7859366076Scy** [sqlite3_str_new()] must be freed by a subsequent call to 7860342292Scy** [sqlite3_str_finish(X)]. 7861342292Scy** 7862342292Scy** ^The [sqlite3_str_new(D)] interface always returns a pointer to a 7863342292Scy** valid [sqlite3_str] object, though in the event of an out-of-memory 7864342292Scy** error the returned object might be a special singleton that will 7865366076Scy** silently reject new text, always return SQLITE_NOMEM from 7866366076Scy** [sqlite3_str_errcode()], always return 0 for 7867342292Scy** [sqlite3_str_length()], and always return NULL from 7868342292Scy** [sqlite3_str_finish(X)]. It is always safe to use the value 7869342292Scy** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter 7870342292Scy** to any of the other [sqlite3_str] methods. 7871342292Scy** 7872342292Scy** The D parameter to [sqlite3_str_new(D)] may be NULL. If the 7873342292Scy** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum 7874342292Scy** length of the string contained in the [sqlite3_str] object will be 7875342292Scy** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead 7876342292Scy** of [SQLITE_MAX_LENGTH]. 7877342292Scy*/ 7878342292ScySQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*); 7879342292Scy 7880342292Scy/* 7881342292Scy** CAPI3REF: Finalize A Dynamic String 7882342292Scy** DESTRUCTOR: sqlite3_str 7883342292Scy** 7884342292Scy** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X 7885342292Scy** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()] 7886342292Scy** that contains the constructed string. The calling application should 7887342292Scy** pass the returned value to [sqlite3_free()] to avoid a memory leak. 7888342292Scy** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any 7889342292Scy** errors were encountered during construction of the string. ^The 7890342292Scy** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the 7891342292Scy** string in [sqlite3_str] object X is zero bytes long. 7892342292Scy*/ 7893342292ScySQLITE_API char *sqlite3_str_finish(sqlite3_str*); 7894342292Scy 7895342292Scy/* 7896342292Scy** CAPI3REF: Add Content To A Dynamic String 7897342292Scy** METHOD: sqlite3_str 7898342292Scy** 7899342292Scy** These interfaces add content to an sqlite3_str object previously obtained 7900342292Scy** from [sqlite3_str_new()]. 7901342292Scy** 7902366076Scy** ^The [sqlite3_str_appendf(X,F,...)] and 7903342292Scy** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf] 7904366076Scy** functionality of SQLite to append formatted text onto the end of 7905342292Scy** [sqlite3_str] object X. 7906342292Scy** 7907342292Scy** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S 7908342292Scy** onto the end of the [sqlite3_str] object X. N must be non-negative. 7909342292Scy** S must contain at least N non-zero bytes of content. To append a 7910342292Scy** zero-terminated string in its entirety, use the [sqlite3_str_appendall()] 7911342292Scy** method instead. 7912342292Scy** 7913342292Scy** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of 7914342292Scy** zero-terminated string S onto the end of [sqlite3_str] object X. 7915342292Scy** 7916342292Scy** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the 7917342292Scy** single-byte character C onto the end of [sqlite3_str] object X. 7918342292Scy** ^This method can be used, for example, to add whitespace indentation. 7919342292Scy** 7920342292Scy** ^The [sqlite3_str_reset(X)] method resets the string under construction 7921366076Scy** inside [sqlite3_str] object X back to zero bytes in length. 7922342292Scy** 7923342292Scy** These methods do not return a result code. ^If an error occurs, that fact 7924342292Scy** is recorded in the [sqlite3_str] object and can be recovered by a 7925342292Scy** subsequent call to [sqlite3_str_errcode(X)]. 7926342292Scy*/ 7927342292ScySQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...); 7928342292ScySQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list); 7929342292ScySQLITE_API void sqlite3_str_append(sqlite3_str*, const char *zIn, int N); 7930342292ScySQLITE_API void sqlite3_str_appendall(sqlite3_str*, const char *zIn); 7931342292ScySQLITE_API void sqlite3_str_appendchar(sqlite3_str*, int N, char C); 7932342292ScySQLITE_API void sqlite3_str_reset(sqlite3_str*); 7933342292Scy 7934342292Scy/* 7935342292Scy** CAPI3REF: Status Of A Dynamic String 7936342292Scy** METHOD: sqlite3_str 7937342292Scy** 7938342292Scy** These interfaces return the current status of an [sqlite3_str] object. 7939342292Scy** 7940342292Scy** ^If any prior errors have occurred while constructing the dynamic string 7941342292Scy** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return 7942342292Scy** an appropriate error code. ^The [sqlite3_str_errcode(X)] method returns 7943342292Scy** [SQLITE_NOMEM] following any out-of-memory error, or 7944342292Scy** [SQLITE_TOOBIG] if the size of the dynamic string exceeds 7945342292Scy** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors. 7946342292Scy** 7947342292Scy** ^The [sqlite3_str_length(X)] method returns the current length, in bytes, 7948342292Scy** of the dynamic string under construction in [sqlite3_str] object X. 7949342292Scy** ^The length returned by [sqlite3_str_length(X)] does not include the 7950342292Scy** zero-termination byte. 7951342292Scy** 7952342292Scy** ^The [sqlite3_str_value(X)] method returns a pointer to the current 7953342292Scy** content of the dynamic string under construction in X. The value 7954342292Scy** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X 7955342292Scy** and might be freed or altered by any subsequent method on the same 7956342292Scy** [sqlite3_str] object. Applications must not used the pointer returned 7957342292Scy** [sqlite3_str_value(X)] after any subsequent method call on the same 7958342292Scy** object. ^Applications may change the content of the string returned 7959342292Scy** by [sqlite3_str_value(X)] as long as they do not write into any bytes 7960342292Scy** outside the range of 0 to [sqlite3_str_length(X)] and do not read or 7961342292Scy** write any byte after any subsequent sqlite3_str method call. 7962342292Scy*/ 7963342292ScySQLITE_API int sqlite3_str_errcode(sqlite3_str*); 7964342292ScySQLITE_API int sqlite3_str_length(sqlite3_str*); 7965342292ScySQLITE_API char *sqlite3_str_value(sqlite3_str*); 7966342292Scy 7967342292Scy/* 7968251883Speter** CAPI3REF: SQLite Runtime Status 7969251883Speter** 7970282328Sbapt** ^These interfaces are used to retrieve runtime status information 7971251883Speter** about the performance of SQLite, and optionally to reset various 7972251883Speter** highwater marks. ^The first argument is an integer code for 7973251883Speter** the specific parameter to measure. ^(Recognized integer codes 7974251883Speter** are of the form [status parameters | SQLITE_STATUS_...].)^ 7975251883Speter** ^The current value of the parameter is returned into *pCurrent. 7976251883Speter** ^The highest recorded value is returned in *pHighwater. ^If the 7977251883Speter** resetFlag is true, then the highest record value is reset after 7978251883Speter** *pHighwater is written. ^(Some parameters do not record the highest 7979251883Speter** value. For those parameters 7980251883Speter** nothing is written into *pHighwater and the resetFlag is ignored.)^ 7981251883Speter** ^(Other parameters record only the highwater mark and not the current 7982251883Speter** value. For these latter parameters nothing is written into *pCurrent.)^ 7983251883Speter** 7984282328Sbapt** ^The sqlite3_status() and sqlite3_status64() routines return 7985282328Sbapt** SQLITE_OK on success and a non-zero [error code] on failure. 7986251883Speter** 7987282328Sbapt** If either the current value or the highwater mark is too large to 7988282328Sbapt** be represented by a 32-bit integer, then the values returned by 7989282328Sbapt** sqlite3_status() are undefined. 7990251883Speter** 7991251883Speter** See also: [sqlite3_db_status()] 7992251883Speter*/ 7993322444SpeterSQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag); 7994322444SpeterSQLITE_API int sqlite3_status64( 7995282328Sbapt int op, 7996282328Sbapt sqlite3_int64 *pCurrent, 7997282328Sbapt sqlite3_int64 *pHighwater, 7998282328Sbapt int resetFlag 7999282328Sbapt); 8000251883Speter 8001251883Speter 8002251883Speter/* 8003251883Speter** CAPI3REF: Status Parameters 8004251883Speter** KEYWORDS: {status parameters} 8005251883Speter** 8006251883Speter** These integer constants designate various run-time status parameters 8007251883Speter** that can be returned by [sqlite3_status()]. 8008251883Speter** 8009251883Speter** <dl> 8010251883Speter** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt> 8011251883Speter** <dd>This parameter is the current amount of memory checked out 8012251883Speter** using [sqlite3_malloc()], either directly or indirectly. The 8013251883Speter** figure includes calls made to [sqlite3_malloc()] by the application 8014342292Scy** and internal memory usage by the SQLite library. Auxiliary page-cache 8015251883Speter** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in 8016251883Speter** this parameter. The amount returned is the sum of the allocation 8017251883Speter** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^ 8018251883Speter** 8019251883Speter** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt> 8020251883Speter** <dd>This parameter records the largest memory allocation request 8021251883Speter** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their 8022251883Speter** internal equivalents). Only the value returned in the 8023366076Scy** *pHighwater parameter to [sqlite3_status()] is of interest. 8024251883Speter** The value written into the *pCurrent parameter is undefined.</dd>)^ 8025251883Speter** 8026251883Speter** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt> 8027251883Speter** <dd>This parameter records the number of separate memory allocations 8028251883Speter** currently checked out.</dd>)^ 8029251883Speter** 8030251883Speter** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt> 8031251883Speter** <dd>This parameter returns the number of pages used out of the 8032366076Scy** [pagecache memory allocator] that was configured using 8033251883Speter** [SQLITE_CONFIG_PAGECACHE]. The 8034251883Speter** value returned is in pages, not in bytes.</dd>)^ 8035251883Speter** 8036366076Scy** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] 8037251883Speter** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt> 8038251883Speter** <dd>This parameter returns the number of bytes of page cache 8039251883Speter** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE] 8040251883Speter** buffer and where forced to overflow to [sqlite3_malloc()]. The 8041251883Speter** returned value includes allocations that overflowed because they 8042251883Speter** where too large (they were larger than the "sz" parameter to 8043251883Speter** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because 8044251883Speter** no space was left in the page cache.</dd>)^ 8045251883Speter** 8046251883Speter** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt> 8047251883Speter** <dd>This parameter records the largest memory allocation request 8048361456Scy** handed to the [pagecache memory allocator]. Only the value returned in the 8049366076Scy** *pHighwater parameter to [sqlite3_status()] is of interest. 8050251883Speter** The value written into the *pCurrent parameter is undefined.</dd>)^ 8051251883Speter** 8052342292Scy** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt> 8053342292Scy** <dd>No longer used.</dd> 8054251883Speter** 8055251883Speter** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt> 8056342292Scy** <dd>No longer used.</dd> 8057251883Speter** 8058342292Scy** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt> 8059342292Scy** <dd>No longer used.</dd> 8060251883Speter** 8061251883Speter** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt> 8062366076Scy** <dd>The *pHighwater parameter records the deepest parser stack. 8063298161Sbapt** The *pCurrent value is undefined. The *pHighwater value is only 8064251883Speter** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^ 8065251883Speter** </dl> 8066251883Speter** 8067251883Speter** New status parameters may be added from time to time. 8068251883Speter*/ 8069251883Speter#define SQLITE_STATUS_MEMORY_USED 0 8070251883Speter#define SQLITE_STATUS_PAGECACHE_USED 1 8071251883Speter#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 8072342292Scy#define SQLITE_STATUS_SCRATCH_USED 3 /* NOT USED */ 8073342292Scy#define SQLITE_STATUS_SCRATCH_OVERFLOW 4 /* NOT USED */ 8074251883Speter#define SQLITE_STATUS_MALLOC_SIZE 5 8075251883Speter#define SQLITE_STATUS_PARSER_STACK 6 8076251883Speter#define SQLITE_STATUS_PAGECACHE_SIZE 7 8077342292Scy#define SQLITE_STATUS_SCRATCH_SIZE 8 /* NOT USED */ 8078251883Speter#define SQLITE_STATUS_MALLOC_COUNT 9 8079251883Speter 8080251883Speter/* 8081251883Speter** CAPI3REF: Database Connection Status 8082286510Speter** METHOD: sqlite3 8083251883Speter** 8084366076Scy** ^This interface is used to retrieve runtime status information 8085251883Speter** about a single [database connection]. ^The first argument is the 8086251883Speter** database connection object to be interrogated. ^The second argument 8087251883Speter** is an integer constant, taken from the set of 8088251883Speter** [SQLITE_DBSTATUS options], that 8089366076Scy** determines the parameter to interrogate. The set of 8090251883Speter** [SQLITE_DBSTATUS options] is likely 8091251883Speter** to grow in future releases of SQLite. 8092251883Speter** 8093251883Speter** ^The current value of the requested parameter is written into *pCur 8094251883Speter** and the highest instantaneous value is written into *pHiwtr. ^If 8095251883Speter** the resetFlg is true, then the highest instantaneous value is 8096251883Speter** reset back down to the current value. 8097251883Speter** 8098251883Speter** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a 8099251883Speter** non-zero [error code] on failure. 8100251883Speter** 8101251883Speter** See also: [sqlite3_status()] and [sqlite3_stmt_status()]. 8102251883Speter*/ 8103322444SpeterSQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg); 8104251883Speter 8105251883Speter/* 8106251883Speter** CAPI3REF: Status Parameters for database connections 8107251883Speter** KEYWORDS: {SQLITE_DBSTATUS options} 8108251883Speter** 8109251883Speter** These constants are the available integer "verbs" that can be passed as 8110251883Speter** the second argument to the [sqlite3_db_status()] interface. 8111251883Speter** 8112251883Speter** New verbs may be added in future releases of SQLite. Existing verbs 8113251883Speter** might be discontinued. Applications should check the return code from 8114251883Speter** [sqlite3_db_status()] to make sure that the call worked. 8115251883Speter** The [sqlite3_db_status()] interface will return a non-zero error code 8116251883Speter** if a discontinued or unsupported verb is invoked. 8117251883Speter** 8118251883Speter** <dl> 8119251883Speter** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt> 8120251883Speter** <dd>This parameter returns the number of lookaside memory slots currently 8121251883Speter** checked out.</dd>)^ 8122251883Speter** 8123251883Speter** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt> 8124366076Scy** <dd>This parameter returns the number of malloc attempts that were 8125251883Speter** satisfied using lookaside memory. Only the high-water value is meaningful; 8126251883Speter** the current value is always zero.)^ 8127251883Speter** 8128251883Speter** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]] 8129251883Speter** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt> 8130251883Speter** <dd>This parameter returns the number malloc attempts that might have 8131251883Speter** been satisfied using lookaside memory but failed due to the amount of 8132251883Speter** memory requested being larger than the lookaside slot size. 8133251883Speter** Only the high-water value is meaningful; 8134251883Speter** the current value is always zero.)^ 8135251883Speter** 8136251883Speter** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]] 8137251883Speter** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt> 8138251883Speter** <dd>This parameter returns the number malloc attempts that might have 8139251883Speter** been satisfied using lookaside memory but failed due to all lookaside 8140251883Speter** memory already being in use. 8141251883Speter** Only the high-water value is meaningful; 8142251883Speter** the current value is always zero.)^ 8143251883Speter** 8144251883Speter** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt> 8145274884Sbapt** <dd>This parameter returns the approximate number of bytes of heap 8146251883Speter** memory used by all pager caches associated with the database connection.)^ 8147251883Speter** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0. 8148251883Speter** 8149366076Scy** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]] 8150305002Scy** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt> 8151305002Scy** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a 8152305002Scy** pager cache is shared between two or more connections the bytes of heap 8153305002Scy** memory used by that pager cache is divided evenly between the attached 8154305002Scy** connections.)^ In other words, if none of the pager caches associated 8155305002Scy** with the database connection are shared, this request returns the same 8156305002Scy** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are 8157305002Scy** shared, the value returned by this call will be smaller than that returned 8158305002Scy** by DBSTATUS_CACHE_USED. ^The highwater mark associated with 8159305002Scy** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0. 8160305002Scy** 8161251883Speter** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt> 8162274884Sbapt** <dd>This parameter returns the approximate number of bytes of heap 8163251883Speter** memory used to store the schema for all databases associated 8164366076Scy** with the connection - main, temp, and any [ATTACH]-ed databases.)^ 8165251883Speter** ^The full amount of memory used by the schemas is reported, even if the 8166251883Speter** schema memory is shared with other database connections due to 8167251883Speter** [shared cache mode] being enabled. 8168251883Speter** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0. 8169251883Speter** 8170251883Speter** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt> 8171274884Sbapt** <dd>This parameter returns the approximate number of bytes of heap 8172251883Speter** and lookaside memory used by all prepared statements associated with 8173251883Speter** the database connection.)^ 8174251883Speter** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0. 8175251883Speter** </dd> 8176251883Speter** 8177251883Speter** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt> 8178251883Speter** <dd>This parameter returns the number of pager cache hits that have 8179366076Scy** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT 8180251883Speter** is always 0. 8181251883Speter** </dd> 8182251883Speter** 8183251883Speter** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt> 8184251883Speter** <dd>This parameter returns the number of pager cache misses that have 8185366076Scy** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS 8186251883Speter** is always 0. 8187251883Speter** </dd> 8188251883Speter** 8189251883Speter** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt> 8190251883Speter** <dd>This parameter returns the number of dirty cache entries that have 8191251883Speter** been written to disk. Specifically, the number of pages written to the 8192251883Speter** wal file in wal mode databases, or the number of pages written to the 8193251883Speter** database file in rollback mode databases. Any pages written as part of 8194251883Speter** transaction rollback or database recovery operations are not included. 8195251883Speter** If an IO or other error occurs while writing a page to disk, the effect 8196251883Speter** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The 8197251883Speter** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0. 8198251883Speter** </dd> 8199269851Speter** 8200342292Scy** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(<dt>SQLITE_DBSTATUS_CACHE_SPILL</dt> 8201342292Scy** <dd>This parameter returns the number of dirty cache entries that have 8202342292Scy** been written to disk in the middle of a transaction due to the page 8203342292Scy** cache overflowing. Transactions are more efficient if they are written 8204342292Scy** to disk all at once. When pages spill mid-transaction, that introduces 8205342292Scy** additional overhead. This parameter can be used help identify 8206361456Scy** inefficiencies that can be resolved by increasing the cache size. 8207342292Scy** </dd> 8208342292Scy** 8209269851Speter** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt> 8210269851Speter** <dd>This parameter returns zero for the current value if and only if 8211269851Speter** all foreign key constraints (deferred or immediate) have been 8212269851Speter** resolved.)^ ^The highwater mark is always 0. 8213269851Speter** </dd> 8214251883Speter** </dl> 8215251883Speter*/ 8216251883Speter#define SQLITE_DBSTATUS_LOOKASIDE_USED 0 8217251883Speter#define SQLITE_DBSTATUS_CACHE_USED 1 8218251883Speter#define SQLITE_DBSTATUS_SCHEMA_USED 2 8219251883Speter#define SQLITE_DBSTATUS_STMT_USED 3 8220251883Speter#define SQLITE_DBSTATUS_LOOKASIDE_HIT 4 8221251883Speter#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5 8222251883Speter#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6 8223251883Speter#define SQLITE_DBSTATUS_CACHE_HIT 7 8224251883Speter#define SQLITE_DBSTATUS_CACHE_MISS 8 8225251883Speter#define SQLITE_DBSTATUS_CACHE_WRITE 9 8226269851Speter#define SQLITE_DBSTATUS_DEFERRED_FKS 10 8227305002Scy#define SQLITE_DBSTATUS_CACHE_USED_SHARED 11 8228342292Scy#define SQLITE_DBSTATUS_CACHE_SPILL 12 8229342292Scy#define SQLITE_DBSTATUS_MAX 12 /* Largest defined DBSTATUS */ 8230251883Speter 8231251883Speter 8232251883Speter/* 8233251883Speter** CAPI3REF: Prepared Statement Status 8234286510Speter** METHOD: sqlite3_stmt 8235251883Speter** 8236251883Speter** ^(Each prepared statement maintains various 8237251883Speter** [SQLITE_STMTSTATUS counters] that measure the number 8238251883Speter** of times it has performed specific operations.)^ These counters can 8239251883Speter** be used to monitor the performance characteristics of the prepared 8240251883Speter** statements. For example, if the number of table steps greatly exceeds 8241251883Speter** the number of table searches or result rows, that would tend to indicate 8242251883Speter** that the prepared statement is using a full table scan rather than 8243366076Scy** an index. 8244251883Speter** 8245251883Speter** ^(This interface is used to retrieve and reset counter values from 8246251883Speter** a [prepared statement]. The first argument is the prepared statement 8247251883Speter** object to be interrogated. The second argument 8248251883Speter** is an integer code for a specific [SQLITE_STMTSTATUS counter] 8249251883Speter** to be interrogated.)^ 8250251883Speter** ^The current value of the requested counter is returned. 8251251883Speter** ^If the resetFlg is true, then the counter is reset to zero after this 8252251883Speter** interface call returns. 8253251883Speter** 8254251883Speter** See also: [sqlite3_status()] and [sqlite3_db_status()]. 8255251883Speter*/ 8256322444SpeterSQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg); 8257251883Speter 8258251883Speter/* 8259251883Speter** CAPI3REF: Status Parameters for prepared statements 8260251883Speter** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters} 8261251883Speter** 8262251883Speter** These preprocessor macros define integer codes that name counter 8263251883Speter** values associated with the [sqlite3_stmt_status()] interface. 8264251883Speter** The meanings of the various counters are as follows: 8265251883Speter** 8266251883Speter** <dl> 8267251883Speter** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt> 8268251883Speter** <dd>^This is the number of times that SQLite has stepped forward in 8269251883Speter** a table as part of a full table scan. Large numbers for this counter 8270366076Scy** may indicate opportunities for performance improvement through 8271251883Speter** careful use of indices.</dd> 8272251883Speter** 8273251883Speter** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt> 8274251883Speter** <dd>^This is the number of sort operations that have occurred. 8275251883Speter** A non-zero value in this counter may indicate an opportunity to 8276251883Speter** improvement performance through careful use of indices.</dd> 8277251883Speter** 8278251883Speter** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt> 8279251883Speter** <dd>^This is the number of rows inserted into transient indices that 8280251883Speter** were created automatically in order to help joins run faster. 8281251883Speter** A non-zero value in this counter may indicate an opportunity to 8282251883Speter** improvement performance by adding permanent indices that do not 8283251883Speter** need to be reinitialized each time the statement is run.</dd> 8284269851Speter** 8285269851Speter** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt> 8286269851Speter** <dd>^This is the number of virtual machine operations executed 8287269851Speter** by the prepared statement if that number is less than or equal 8288366076Scy** to 2147483647. The number of virtual machine operations can be 8289269851Speter** used as a proxy for the total work done by the prepared statement. 8290269851Speter** If the number of virtual machine operations exceeds 2147483647 8291269851Speter** then the value returned by this statement status code is undefined. 8292322444Speter** 8293322444Speter** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt> 8294322444Speter** <dd>^This is the number of times that the prepare statement has been 8295366076Scy** automatically regenerated due to schema changes or changes to 8296322444Speter** [bound parameters] that might affect the query plan. 8297322444Speter** 8298322444Speter** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt> 8299322444Speter** <dd>^This is the number of times that the prepared statement has 8300322444Speter** been run. A single "run" for the purposes of this counter is one 8301322444Speter** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()]. 8302322444Speter** The counter is incremented on the first [sqlite3_step()] call of each 8303322444Speter** cycle. 8304322444Speter** 8305322444Speter** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt> 8306322444Speter** <dd>^This is the approximate number of bytes of heap memory 8307322444Speter** used to store the prepared statement. ^This value is not actually 8308322444Speter** a counter, and so the resetFlg parameter to sqlite3_stmt_status() 8309322444Speter** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED. 8310269851Speter** </dd> 8311251883Speter** </dl> 8312251883Speter*/ 8313251883Speter#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1 8314251883Speter#define SQLITE_STMTSTATUS_SORT 2 8315251883Speter#define SQLITE_STMTSTATUS_AUTOINDEX 3 8316269851Speter#define SQLITE_STMTSTATUS_VM_STEP 4 8317322444Speter#define SQLITE_STMTSTATUS_REPREPARE 5 8318322444Speter#define SQLITE_STMTSTATUS_RUN 6 8319322444Speter#define SQLITE_STMTSTATUS_MEMUSED 99 8320251883Speter 8321251883Speter/* 8322251883Speter** CAPI3REF: Custom Page Cache Object 8323251883Speter** 8324251883Speter** The sqlite3_pcache type is opaque. It is implemented by 8325251883Speter** the pluggable module. The SQLite core has no knowledge of 8326251883Speter** its size or internal structure and never deals with the 8327251883Speter** sqlite3_pcache object except by holding and passing pointers 8328251883Speter** to the object. 8329251883Speter** 8330251883Speter** See [sqlite3_pcache_methods2] for additional information. 8331251883Speter*/ 8332251883Spetertypedef struct sqlite3_pcache sqlite3_pcache; 8333251883Speter 8334251883Speter/* 8335251883Speter** CAPI3REF: Custom Page Cache Object 8336251883Speter** 8337251883Speter** The sqlite3_pcache_page object represents a single page in the 8338251883Speter** page cache. The page cache will allocate instances of this 8339251883Speter** object. Various methods of the page cache use pointers to instances 8340251883Speter** of this object as parameters or as their return value. 8341251883Speter** 8342251883Speter** See [sqlite3_pcache_methods2] for additional information. 8343251883Speter*/ 8344251883Spetertypedef struct sqlite3_pcache_page sqlite3_pcache_page; 8345251883Speterstruct sqlite3_pcache_page { 8346251883Speter void *pBuf; /* The content of the page */ 8347251883Speter void *pExtra; /* Extra information associated with the page */ 8348251883Speter}; 8349251883Speter 8350251883Speter/* 8351251883Speter** CAPI3REF: Application Defined Page Cache. 8352251883Speter** KEYWORDS: {page cache} 8353251883Speter** 8354251883Speter** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can 8355366076Scy** register an alternative page cache implementation by passing in an 8356251883Speter** instance of the sqlite3_pcache_methods2 structure.)^ 8357366076Scy** In many applications, most of the heap memory allocated by 8358251883Speter** SQLite is used for the page cache. 8359366076Scy** By implementing a 8360251883Speter** custom page cache using this API, an application can better control 8361366076Scy** the amount of memory consumed by SQLite, the way in which 8362366076Scy** that memory is allocated and released, and the policies used to 8363366076Scy** determine exactly which parts of a database file are cached and for 8364251883Speter** how long. 8365251883Speter** 8366251883Speter** The alternative page cache mechanism is an 8367251883Speter** extreme measure that is only needed by the most demanding applications. 8368251883Speter** The built-in page cache is recommended for most uses. 8369251883Speter** 8370251883Speter** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an 8371251883Speter** internal buffer by SQLite within the call to [sqlite3_config]. Hence 8372251883Speter** the application may discard the parameter after the call to 8373251883Speter** [sqlite3_config()] returns.)^ 8374251883Speter** 8375251883Speter** [[the xInit() page cache method]] 8376366076Scy** ^(The xInit() method is called once for each effective 8377251883Speter** call to [sqlite3_initialize()])^ 8378251883Speter** (usually only once during the lifetime of the process). ^(The xInit() 8379251883Speter** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^ 8380366076Scy** The intent of the xInit() method is to set up global data structures 8381366076Scy** required by the custom page cache implementation. 8382366076Scy** ^(If the xInit() method is NULL, then the 8383251883Speter** built-in default page cache is used instead of the application defined 8384251883Speter** page cache.)^ 8385251883Speter** 8386251883Speter** [[the xShutdown() page cache method]] 8387251883Speter** ^The xShutdown() method is called by [sqlite3_shutdown()]. 8388366076Scy** It can be used to clean up 8389251883Speter** any outstanding resources before process shutdown, if required. 8390251883Speter** ^The xShutdown() method may be NULL. 8391251883Speter** 8392251883Speter** ^SQLite automatically serializes calls to the xInit method, 8393251883Speter** so the xInit method need not be threadsafe. ^The 8394251883Speter** xShutdown method is only called from [sqlite3_shutdown()] so it does 8395251883Speter** not need to be threadsafe either. All other methods must be threadsafe 8396251883Speter** in multithreaded applications. 8397251883Speter** 8398251883Speter** ^SQLite will never invoke xInit() more than once without an intervening 8399251883Speter** call to xShutdown(). 8400251883Speter** 8401251883Speter** [[the xCreate() page cache methods]] 8402251883Speter** ^SQLite invokes the xCreate() method to construct a new cache instance. 8403251883Speter** SQLite will typically create one cache instance for each open database file, 8404251883Speter** though this is not guaranteed. ^The 8405251883Speter** first parameter, szPage, is the size in bytes of the pages that must 8406251883Speter** be allocated by the cache. ^szPage will always a power of two. ^The 8407366076Scy** second parameter szExtra is a number of bytes of extra storage 8408251883Speter** associated with each page cache entry. ^The szExtra parameter will 8409251883Speter** a number less than 250. SQLite will use the 8410251883Speter** extra szExtra bytes on each page to store metadata about the underlying 8411251883Speter** database page on disk. The value passed into szExtra depends 8412251883Speter** on the SQLite version, the target platform, and how SQLite was compiled. 8413251883Speter** ^The third argument to xCreate(), bPurgeable, is true if the cache being 8414251883Speter** created will be used to cache database pages of a file stored on disk, or 8415251883Speter** false if it is used for an in-memory database. The cache implementation 8416251883Speter** does not have to do anything special based with the value of bPurgeable; 8417251883Speter** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will 8418251883Speter** never invoke xUnpin() except to deliberately delete a page. 8419251883Speter** ^In other words, calls to xUnpin() on a cache with bPurgeable set to 8420366076Scy** false will always have the "discard" flag set to true. 8421251883Speter** ^Hence, a cache created with bPurgeable false will 8422251883Speter** never contain any unpinned pages. 8423251883Speter** 8424251883Speter** [[the xCachesize() page cache method]] 8425251883Speter** ^(The xCachesize() method may be called at any time by SQLite to set the 8426251883Speter** suggested maximum cache-size (number of pages stored by) the cache 8427251883Speter** instance passed as the first argument. This is the value configured using 8428251883Speter** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable 8429251883Speter** parameter, the implementation is not required to do anything with this 8430251883Speter** value; it is advisory only. 8431251883Speter** 8432251883Speter** [[the xPagecount() page cache methods]] 8433251883Speter** The xPagecount() method must return the number of pages currently 8434251883Speter** stored in the cache, both pinned and unpinned. 8435366076Scy** 8436251883Speter** [[the xFetch() page cache methods]] 8437366076Scy** The xFetch() method locates a page in the cache and returns a pointer to 8438251883Speter** an sqlite3_pcache_page object associated with that page, or a NULL pointer. 8439251883Speter** The pBuf element of the returned sqlite3_pcache_page object will be a 8440366076Scy** pointer to a buffer of szPage bytes used to store the content of a 8441251883Speter** single database page. The pExtra element of sqlite3_pcache_page will be 8442251883Speter** a pointer to the szExtra bytes of extra storage that SQLite has requested 8443251883Speter** for each entry in the page cache. 8444251883Speter** 8445251883Speter** The page to be fetched is determined by the key. ^The minimum key value 8446251883Speter** is 1. After it has been retrieved using xFetch, the page is considered 8447251883Speter** to be "pinned". 8448251883Speter** 8449251883Speter** If the requested page is already in the page cache, then the page cache 8450251883Speter** implementation must return a pointer to the page buffer with its content 8451251883Speter** intact. If the requested page is not already in the cache, then the 8452251883Speter** cache implementation should use the value of the createFlag 8453251883Speter** parameter to help it determined what action to take: 8454251883Speter** 8455251883Speter** <table border=1 width=85% align=center> 8456251883Speter** <tr><th> createFlag <th> Behavior when page is not already in cache 8457251883Speter** <tr><td> 0 <td> Do not allocate a new page. Return NULL. 8458251883Speter** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so. 8459251883Speter** Otherwise return NULL. 8460251883Speter** <tr><td> 2 <td> Make every effort to allocate a new page. Only return 8461251883Speter** NULL if allocating a new page is effectively impossible. 8462251883Speter** </table> 8463251883Speter** 8464251883Speter** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite 8465251883Speter** will only use a createFlag of 2 after a prior call with a createFlag of 1 8466361456Scy** failed.)^ In between the xFetch() calls, SQLite may 8467251883Speter** attempt to unpin one or more cache pages by spilling the content of 8468251883Speter** pinned pages to disk and synching the operating system disk cache. 8469251883Speter** 8470251883Speter** [[the xUnpin() page cache method]] 8471251883Speter** ^xUnpin() is called by SQLite with a pointer to a currently pinned page 8472251883Speter** as its second argument. If the third parameter, discard, is non-zero, 8473251883Speter** then the page must be evicted from the cache. 8474251883Speter** ^If the discard parameter is 8475251883Speter** zero, then the page may be discarded or retained at the discretion of 8476251883Speter** page cache implementation. ^The page cache implementation 8477251883Speter** may choose to evict unpinned pages at any time. 8478251883Speter** 8479366076Scy** The cache must not perform any reference counting. A single 8480366076Scy** call to xUnpin() unpins the page regardless of the number of prior calls 8481251883Speter** to xFetch(). 8482251883Speter** 8483251883Speter** [[the xRekey() page cache methods]] 8484251883Speter** The xRekey() method is used to change the key value associated with the 8485251883Speter** page passed as the second argument. If the cache 8486251883Speter** previously contains an entry associated with newKey, it must be 8487251883Speter** discarded. ^Any prior cache entry associated with newKey is guaranteed not 8488251883Speter** to be pinned. 8489251883Speter** 8490251883Speter** When SQLite calls the xTruncate() method, the cache must discard all 8491251883Speter** existing cache entries with page numbers (keys) greater than or equal 8492251883Speter** to the value of the iLimit parameter passed to xTruncate(). If any 8493251883Speter** of these pages are pinned, they are implicitly unpinned, meaning that 8494251883Speter** they can be safely discarded. 8495251883Speter** 8496251883Speter** [[the xDestroy() page cache method]] 8497251883Speter** ^The xDestroy() method is used to delete a cache allocated by xCreate(). 8498251883Speter** All resources associated with the specified cache should be freed. ^After 8499251883Speter** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*] 8500251883Speter** handle invalid, and will not use it with any other sqlite3_pcache_methods2 8501251883Speter** functions. 8502251883Speter** 8503251883Speter** [[the xShrink() page cache method]] 8504251883Speter** ^SQLite invokes the xShrink() method when it wants the page cache to 8505251883Speter** free up as much of heap memory as possible. The page cache implementation 8506251883Speter** is not obligated to free any memory, but well-behaved implementations should 8507251883Speter** do their best. 8508251883Speter*/ 8509251883Spetertypedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2; 8510251883Speterstruct sqlite3_pcache_methods2 { 8511251883Speter int iVersion; 8512251883Speter void *pArg; 8513251883Speter int (*xInit)(void*); 8514251883Speter void (*xShutdown)(void*); 8515251883Speter sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable); 8516251883Speter void (*xCachesize)(sqlite3_pcache*, int nCachesize); 8517251883Speter int (*xPagecount)(sqlite3_pcache*); 8518251883Speter sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 8519251883Speter void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard); 8520366076Scy void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*, 8521251883Speter unsigned oldKey, unsigned newKey); 8522251883Speter void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 8523251883Speter void (*xDestroy)(sqlite3_pcache*); 8524251883Speter void (*xShrink)(sqlite3_pcache*); 8525251883Speter}; 8526251883Speter 8527251883Speter/* 8528251883Speter** This is the obsolete pcache_methods object that has now been replaced 8529251883Speter** by sqlite3_pcache_methods2. This object is not used by SQLite. It is 8530251883Speter** retained in the header file for backwards compatibility only. 8531251883Speter*/ 8532251883Spetertypedef struct sqlite3_pcache_methods sqlite3_pcache_methods; 8533251883Speterstruct sqlite3_pcache_methods { 8534251883Speter void *pArg; 8535251883Speter int (*xInit)(void*); 8536251883Speter void (*xShutdown)(void*); 8537251883Speter sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable); 8538251883Speter void (*xCachesize)(sqlite3_pcache*, int nCachesize); 8539251883Speter int (*xPagecount)(sqlite3_pcache*); 8540251883Speter void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 8541251883Speter void (*xUnpin)(sqlite3_pcache*, void*, int discard); 8542251883Speter void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey); 8543251883Speter void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 8544251883Speter void (*xDestroy)(sqlite3_pcache*); 8545251883Speter}; 8546251883Speter 8547251883Speter 8548251883Speter/* 8549251883Speter** CAPI3REF: Online Backup Object 8550251883Speter** 8551251883Speter** The sqlite3_backup object records state information about an ongoing 8552251883Speter** online backup operation. ^The sqlite3_backup object is created by 8553251883Speter** a call to [sqlite3_backup_init()] and is destroyed by a call to 8554251883Speter** [sqlite3_backup_finish()]. 8555251883Speter** 8556251883Speter** See Also: [Using the SQLite Online Backup API] 8557251883Speter*/ 8558251883Spetertypedef struct sqlite3_backup sqlite3_backup; 8559251883Speter 8560251883Speter/* 8561251883Speter** CAPI3REF: Online Backup API. 8562251883Speter** 8563251883Speter** The backup API copies the content of one database into another. 8564251883Speter** It is useful either for creating backups of databases or 8565366076Scy** for copying in-memory databases to or from persistent files. 8566251883Speter** 8567251883Speter** See Also: [Using the SQLite Online Backup API] 8568251883Speter** 8569251883Speter** ^SQLite holds a write transaction open on the destination database file 8570251883Speter** for the duration of the backup operation. 8571251883Speter** ^The source database is read-locked only while it is being read; 8572251883Speter** it is not locked continuously for the entire backup operation. 8573251883Speter** ^Thus, the backup may be performed on a live source database without 8574251883Speter** preventing other database connections from 8575251883Speter** reading or writing to the source database while the backup is underway. 8576366076Scy** 8577366076Scy** ^(To perform a backup operation: 8578251883Speter** <ol> 8579251883Speter** <li><b>sqlite3_backup_init()</b> is called once to initialize the 8580366076Scy** backup, 8581366076Scy** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer 8582251883Speter** the data between the two databases, and finally 8583366076Scy** <li><b>sqlite3_backup_finish()</b> is called to release all resources 8584366076Scy** associated with the backup operation. 8585251883Speter** </ol>)^ 8586251883Speter** There should be exactly one call to sqlite3_backup_finish() for each 8587251883Speter** successful call to sqlite3_backup_init(). 8588251883Speter** 8589251883Speter** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b> 8590251883Speter** 8591366076Scy** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the 8592366076Scy** [database connection] associated with the destination database 8593251883Speter** and the database name, respectively. 8594251883Speter** ^The database name is "main" for the main database, "temp" for the 8595251883Speter** temporary database, or the name specified after the AS keyword in 8596251883Speter** an [ATTACH] statement for an attached database. 8597366076Scy** ^The S and M arguments passed to 8598251883Speter** sqlite3_backup_init(D,N,S,M) identify the [database connection] 8599251883Speter** and database name of the source database, respectively. 8600251883Speter** ^The source and destination [database connections] (parameters S and D) 8601251883Speter** must be different or else sqlite3_backup_init(D,N,S,M) will fail with 8602251883Speter** an error. 8603251883Speter** 8604366076Scy** ^A call to sqlite3_backup_init() will fail, returning NULL, if 8605366076Scy** there is already a read or read-write transaction open on the 8606282328Sbapt** destination database. 8607282328Sbapt** 8608251883Speter** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is 8609251883Speter** returned and an error code and error message are stored in the 8610251883Speter** destination [database connection] D. 8611251883Speter** ^The error code and message for the failed call to sqlite3_backup_init() 8612251883Speter** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or 8613251883Speter** [sqlite3_errmsg16()] functions. 8614251883Speter** ^A successful call to sqlite3_backup_init() returns a pointer to an 8615251883Speter** [sqlite3_backup] object. 8616251883Speter** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and 8617366076Scy** sqlite3_backup_finish() functions to perform the specified backup 8618251883Speter** operation. 8619251883Speter** 8620251883Speter** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b> 8621251883Speter** 8622366076Scy** ^Function sqlite3_backup_step(B,N) will copy up to N pages between 8623251883Speter** the source and destination databases specified by [sqlite3_backup] object B. 8624366076Scy** ^If N is negative, all remaining source pages are copied. 8625251883Speter** ^If sqlite3_backup_step(B,N) successfully copies N pages and there 8626251883Speter** are still more pages to be copied, then the function returns [SQLITE_OK]. 8627251883Speter** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages 8628251883Speter** from source to destination, then it returns [SQLITE_DONE]. 8629251883Speter** ^If an error occurs while running sqlite3_backup_step(B,N), 8630251883Speter** then an [error code] is returned. ^As well as [SQLITE_OK] and 8631251883Speter** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY], 8632251883Speter** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an 8633251883Speter** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code. 8634251883Speter** 8635251883Speter** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if 8636251883Speter** <ol> 8637251883Speter** <li> the destination database was opened read-only, or 8638251883Speter** <li> the destination database is using write-ahead-log journaling 8639251883Speter** and the destination and source page sizes differ, or 8640251883Speter** <li> the destination database is an in-memory database and the 8641251883Speter** destination and source page sizes differ. 8642251883Speter** </ol>)^ 8643251883Speter** 8644251883Speter** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then 8645251883Speter** the [sqlite3_busy_handler | busy-handler function] 8646366076Scy** is invoked (if one is specified). ^If the 8647366076Scy** busy-handler returns non-zero before the lock is available, then 8648251883Speter** [SQLITE_BUSY] is returned to the caller. ^In this case the call to 8649251883Speter** sqlite3_backup_step() can be retried later. ^If the source 8650251883Speter** [database connection] 8651251883Speter** is being used to write to the source database when sqlite3_backup_step() 8652251883Speter** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this 8653251883Speter** case the call to sqlite3_backup_step() can be retried later on. ^(If 8654251883Speter** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or 8655366076Scy** [SQLITE_READONLY] is returned, then 8656366076Scy** there is no point in retrying the call to sqlite3_backup_step(). These 8657366076Scy** errors are considered fatal.)^ The application must accept 8658366076Scy** that the backup operation has failed and pass the backup operation handle 8659251883Speter** to the sqlite3_backup_finish() to release associated resources. 8660251883Speter** 8661251883Speter** ^The first call to sqlite3_backup_step() obtains an exclusive lock 8662366076Scy** on the destination file. ^The exclusive lock is not released until either 8663366076Scy** sqlite3_backup_finish() is called or the backup operation is complete 8664251883Speter** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to 8665251883Speter** sqlite3_backup_step() obtains a [shared lock] on the source database that 8666251883Speter** lasts for the duration of the sqlite3_backup_step() call. 8667251883Speter** ^Because the source database is not locked between calls to 8668251883Speter** sqlite3_backup_step(), the source database may be modified mid-way 8669251883Speter** through the backup process. ^If the source database is modified by an 8670251883Speter** external process or via a database connection other than the one being 8671251883Speter** used by the backup operation, then the backup will be automatically 8672366076Scy** restarted by the next call to sqlite3_backup_step(). ^If the source 8673251883Speter** database is modified by the using the same database connection as is used 8674251883Speter** by the backup operation, then the backup database is automatically 8675251883Speter** updated at the same time. 8676251883Speter** 8677251883Speter** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b> 8678251883Speter** 8679366076Scy** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the 8680251883Speter** application wishes to abandon the backup operation, the application 8681251883Speter** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish(). 8682251883Speter** ^The sqlite3_backup_finish() interfaces releases all 8683366076Scy** resources associated with the [sqlite3_backup] object. 8684251883Speter** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any 8685251883Speter** active write-transaction on the destination database is rolled back. 8686251883Speter** The [sqlite3_backup] object is invalid 8687251883Speter** and may not be used following a call to sqlite3_backup_finish(). 8688251883Speter** 8689251883Speter** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no 8690251883Speter** sqlite3_backup_step() errors occurred, regardless or whether or not 8691251883Speter** sqlite3_backup_step() completed. 8692251883Speter** ^If an out-of-memory condition or IO error occurred during any prior 8693251883Speter** sqlite3_backup_step() call on the same [sqlite3_backup] object, then 8694251883Speter** sqlite3_backup_finish() returns the corresponding [error code]. 8695251883Speter** 8696251883Speter** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() 8697251883Speter** is not a permanent error and does not affect the return value of 8698251883Speter** sqlite3_backup_finish(). 8699251883Speter** 8700282328Sbapt** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]] 8701251883Speter** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b> 8702251883Speter** 8703282328Sbapt** ^The sqlite3_backup_remaining() routine returns the number of pages still 8704282328Sbapt** to be backed up at the conclusion of the most recent sqlite3_backup_step(). 8705282328Sbapt** ^The sqlite3_backup_pagecount() routine returns the total number of pages 8706282328Sbapt** in the source database at the conclusion of the most recent 8707282328Sbapt** sqlite3_backup_step(). 8708282328Sbapt** ^(The values returned by these functions are only updated by 8709282328Sbapt** sqlite3_backup_step(). If the source database is modified in a way that 8710282328Sbapt** changes the size of the source database or the number of pages remaining, 8711282328Sbapt** those changes are not reflected in the output of sqlite3_backup_pagecount() 8712282328Sbapt** and sqlite3_backup_remaining() until after the next 8713282328Sbapt** sqlite3_backup_step().)^ 8714251883Speter** 8715251883Speter** <b>Concurrent Usage of Database Handles</b> 8716251883Speter** 8717251883Speter** ^The source [database connection] may be used by the application for other 8718251883Speter** purposes while a backup operation is underway or being initialized. 8719251883Speter** ^If SQLite is compiled and configured to support threadsafe database 8720251883Speter** connections, then the source database connection may be used concurrently 8721251883Speter** from within other threads. 8722251883Speter** 8723366076Scy** However, the application must guarantee that the destination 8724366076Scy** [database connection] is not passed to any other API (by any thread) after 8725251883Speter** sqlite3_backup_init() is called and before the corresponding call to 8726251883Speter** sqlite3_backup_finish(). SQLite does not currently check to see 8727251883Speter** if the application incorrectly accesses the destination [database connection] 8728251883Speter** and so no error code is reported, but the operations may malfunction 8729251883Speter** nevertheless. Use of the destination database connection while a 8730251883Speter** backup is in progress might also also cause a mutex deadlock. 8731251883Speter** 8732251883Speter** If running in [shared cache mode], the application must 8733251883Speter** guarantee that the shared cache used by the destination database 8734251883Speter** is not accessed while the backup is running. In practice this means 8735366076Scy** that the application must guarantee that the disk file being 8736251883Speter** backed up to is not accessed by any connection within the process, 8737251883Speter** not just the specific connection that was passed to sqlite3_backup_init(). 8738251883Speter** 8739366076Scy** The [sqlite3_backup] object itself is partially threadsafe. Multiple 8740251883Speter** threads may safely make multiple concurrent calls to sqlite3_backup_step(). 8741251883Speter** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount() 8742251883Speter** APIs are not strictly speaking threadsafe. If they are invoked at the 8743251883Speter** same time as another thread is invoking sqlite3_backup_step() it is 8744251883Speter** possible that they return invalid values. 8745251883Speter*/ 8746322444SpeterSQLITE_API sqlite3_backup *sqlite3_backup_init( 8747251883Speter sqlite3 *pDest, /* Destination database handle */ 8748251883Speter const char *zDestName, /* Destination database name */ 8749251883Speter sqlite3 *pSource, /* Source database handle */ 8750251883Speter const char *zSourceName /* Source database name */ 8751251883Speter); 8752322444SpeterSQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage); 8753322444SpeterSQLITE_API int sqlite3_backup_finish(sqlite3_backup *p); 8754322444SpeterSQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p); 8755322444SpeterSQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p); 8756251883Speter 8757251883Speter/* 8758251883Speter** CAPI3REF: Unlock Notification 8759286510Speter** METHOD: sqlite3 8760251883Speter** 8761251883Speter** ^When running in shared-cache mode, a database operation may fail with 8762251883Speter** an [SQLITE_LOCKED] error if the required locks on the shared-cache or 8763251883Speter** individual tables within the shared-cache cannot be obtained. See 8764366076Scy** [SQLite Shared-Cache Mode] for a description of shared-cache locking. 8765366076Scy** ^This API may be used to register a callback that SQLite will invoke 8766251883Speter** when the connection currently holding the required lock relinquishes it. 8767251883Speter** ^This API is only available if the library was compiled with the 8768251883Speter** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined. 8769251883Speter** 8770251883Speter** See Also: [Using the SQLite Unlock Notification Feature]. 8771251883Speter** 8772251883Speter** ^Shared-cache locks are released when a database connection concludes 8773366076Scy** its current transaction, either by committing it or rolling it back. 8774251883Speter** 8775251883Speter** ^When a connection (known as the blocked connection) fails to obtain a 8776251883Speter** shared-cache lock and SQLITE_LOCKED is returned to the caller, the 8777251883Speter** identity of the database connection (the blocking connection) that 8778366076Scy** has locked the required resource is stored internally. ^After an 8779251883Speter** application receives an SQLITE_LOCKED error, it may call the 8780366076Scy** sqlite3_unlock_notify() method with the blocked connection handle as 8781251883Speter** the first argument to register for a callback that will be invoked 8782251883Speter** when the blocking connections current transaction is concluded. ^The 8783251883Speter** callback is invoked from within the [sqlite3_step] or [sqlite3_close] 8784361456Scy** call that concludes the blocking connection's transaction. 8785251883Speter** 8786251883Speter** ^(If sqlite3_unlock_notify() is called in a multi-threaded application, 8787251883Speter** there is a chance that the blocking connection will have already 8788251883Speter** concluded its transaction by the time sqlite3_unlock_notify() is invoked. 8789251883Speter** If this happens, then the specified callback is invoked immediately, 8790251883Speter** from within the call to sqlite3_unlock_notify().)^ 8791251883Speter** 8792251883Speter** ^If the blocked connection is attempting to obtain a write-lock on a 8793251883Speter** shared-cache table, and more than one other connection currently holds 8794366076Scy** a read-lock on the same table, then SQLite arbitrarily selects one of 8795251883Speter** the other connections to use as the blocking connection. 8796251883Speter** 8797366076Scy** ^(There may be at most one unlock-notify callback registered by a 8798251883Speter** blocked connection. If sqlite3_unlock_notify() is called when the 8799251883Speter** blocked connection already has a registered unlock-notify callback, 8800251883Speter** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is 8801251883Speter** called with a NULL pointer as its second argument, then any existing 8802366076Scy** unlock-notify callback is canceled. ^The blocked connections 8803251883Speter** unlock-notify callback may also be canceled by closing the blocked 8804251883Speter** connection using [sqlite3_close()]. 8805251883Speter** 8806251883Speter** The unlock-notify callback is not reentrant. If an application invokes 8807251883Speter** any sqlite3_xxx API functions from within an unlock-notify callback, a 8808251883Speter** crash or deadlock may be the result. 8809251883Speter** 8810251883Speter** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always 8811251883Speter** returns SQLITE_OK. 8812251883Speter** 8813251883Speter** <b>Callback Invocation Details</b> 8814251883Speter** 8815366076Scy** When an unlock-notify callback is registered, the application provides a 8816251883Speter** single void* pointer that is passed to the callback when it is invoked. 8817251883Speter** However, the signature of the callback function allows SQLite to pass 8818251883Speter** it an array of void* context pointers. The first argument passed to 8819251883Speter** an unlock-notify callback is a pointer to an array of void* pointers, 8820251883Speter** and the second is the number of entries in the array. 8821251883Speter** 8822361456Scy** When a blocking connection's transaction is concluded, there may be 8823251883Speter** more than one blocked connection that has registered for an unlock-notify 8824251883Speter** callback. ^If two or more such blocked connections have specified the 8825251883Speter** same callback function, then instead of invoking the callback function 8826251883Speter** multiple times, it is invoked once with the set of void* context pointers 8827251883Speter** specified by the blocked connections bundled together into an array. 8828366076Scy** This gives the application an opportunity to prioritize any actions 8829251883Speter** related to the set of unblocked database connections. 8830251883Speter** 8831251883Speter** <b>Deadlock Detection</b> 8832251883Speter** 8833366076Scy** Assuming that after registering for an unlock-notify callback a 8834251883Speter** database waits for the callback to be issued before taking any further 8835251883Speter** action (a reasonable assumption), then using this API may cause the 8836251883Speter** application to deadlock. For example, if connection X is waiting for 8837251883Speter** connection Y's transaction to be concluded, and similarly connection 8838251883Speter** Y is waiting on connection X's transaction, then neither connection 8839251883Speter** will proceed and the system may remain deadlocked indefinitely. 8840251883Speter** 8841251883Speter** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock 8842251883Speter** detection. ^If a given call to sqlite3_unlock_notify() would put the 8843251883Speter** system in a deadlocked state, then SQLITE_LOCKED is returned and no 8844251883Speter** unlock-notify callback is registered. The system is said to be in 8845251883Speter** a deadlocked state if connection A has registered for an unlock-notify 8846251883Speter** callback on the conclusion of connection B's transaction, and connection 8847251883Speter** B has itself registered for an unlock-notify callback when connection 8848251883Speter** A's transaction is concluded. ^Indirect deadlock is also detected, so 8849251883Speter** the system is also considered to be deadlocked if connection B has 8850251883Speter** registered for an unlock-notify callback on the conclusion of connection 8851251883Speter** C's transaction, where connection C is waiting on connection A. ^Any 8852251883Speter** number of levels of indirection are allowed. 8853251883Speter** 8854251883Speter** <b>The "DROP TABLE" Exception</b> 8855251883Speter** 8856366076Scy** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost 8857251883Speter** always appropriate to call sqlite3_unlock_notify(). There is however, 8858251883Speter** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement, 8859251883Speter** SQLite checks if there are any currently executing SELECT statements 8860251883Speter** that belong to the same connection. If there are, SQLITE_LOCKED is 8861251883Speter** returned. In this case there is no "blocking connection", so invoking 8862251883Speter** sqlite3_unlock_notify() results in the unlock-notify callback being 8863251883Speter** invoked immediately. If the application then re-attempts the "DROP TABLE" 8864251883Speter** or "DROP INDEX" query, an infinite loop might be the result. 8865251883Speter** 8866251883Speter** One way around this problem is to check the extended error code returned 8867251883Speter** by an sqlite3_step() call. ^(If there is a blocking connection, then the 8868251883Speter** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in 8869366076Scy** the special "DROP TABLE/INDEX" case, the extended error code is just 8870251883Speter** SQLITE_LOCKED.)^ 8871251883Speter*/ 8872322444SpeterSQLITE_API int sqlite3_unlock_notify( 8873251883Speter sqlite3 *pBlocked, /* Waiting connection */ 8874251883Speter void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */ 8875251883Speter void *pNotifyArg /* Argument to pass to xNotify */ 8876251883Speter); 8877251883Speter 8878251883Speter 8879251883Speter/* 8880251883Speter** CAPI3REF: String Comparison 8881251883Speter** 8882251883Speter** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications 8883251883Speter** and extensions to compare the contents of two buffers containing UTF-8 8884251883Speter** strings in a case-independent fashion, using the same definition of "case 8885251883Speter** independence" that SQLite uses internally when comparing identifiers. 8886251883Speter*/ 8887322444SpeterSQLITE_API int sqlite3_stricmp(const char *, const char *); 8888322444SpeterSQLITE_API int sqlite3_strnicmp(const char *, const char *, int); 8889251883Speter 8890251883Speter/* 8891251883Speter** CAPI3REF: String Globbing 8892251883Speter* 8893298161Sbapt** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if 8894298161Sbapt** string X matches the [GLOB] pattern P. 8895298161Sbapt** ^The definition of [GLOB] pattern matching used in 8896251883Speter** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the 8897298161Sbapt** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function 8898298161Sbapt** is case sensitive. 8899251883Speter** 8900251883Speter** Note that this routine returns zero on a match and non-zero if the strings 8901251883Speter** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. 8902298161Sbapt** 8903298161Sbapt** See also: [sqlite3_strlike()]. 8904251883Speter*/ 8905322444SpeterSQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr); 8906251883Speter 8907251883Speter/* 8908298161Sbapt** CAPI3REF: String LIKE Matching 8909298161Sbapt* 8910298161Sbapt** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if 8911298161Sbapt** string X matches the [LIKE] pattern P with escape character E. 8912298161Sbapt** ^The definition of [LIKE] pattern matching used in 8913298161Sbapt** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E" 8914298161Sbapt** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without 8915298161Sbapt** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0. 8916298161Sbapt** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case 8917298161Sbapt** insensitive - equivalent upper and lower case ASCII characters match 8918298161Sbapt** one another. 8919298161Sbapt** 8920298161Sbapt** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though 8921298161Sbapt** only ASCII characters are case folded. 8922298161Sbapt** 8923298161Sbapt** Note that this routine returns zero on a match and non-zero if the strings 8924298161Sbapt** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. 8925298161Sbapt** 8926298161Sbapt** See also: [sqlite3_strglob()]. 8927298161Sbapt*/ 8928322444SpeterSQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc); 8929298161Sbapt 8930298161Sbapt/* 8931251883Speter** CAPI3REF: Error Logging Interface 8932251883Speter** 8933251883Speter** ^The [sqlite3_log()] interface writes a message into the [error log] 8934251883Speter** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()]. 8935251883Speter** ^If logging is enabled, the zFormat string and subsequent arguments are 8936251883Speter** used with [sqlite3_snprintf()] to generate the final output string. 8937251883Speter** 8938251883Speter** The sqlite3_log() interface is intended for use by extensions such as 8939251883Speter** virtual tables, collating functions, and SQL functions. While there is 8940251883Speter** nothing to prevent an application from calling sqlite3_log(), doing so 8941251883Speter** is considered bad form. 8942251883Speter** 8943251883Speter** The zFormat string must not be NULL. 8944251883Speter** 8945251883Speter** To avoid deadlocks and other threading problems, the sqlite3_log() routine 8946251883Speter** will not use dynamically allocated memory. The log message is stored in 8947251883Speter** a fixed-length buffer on the stack. If the log message is longer than 8948251883Speter** a few hundred characters, it will be truncated to the length of the 8949251883Speter** buffer. 8950251883Speter*/ 8951322444SpeterSQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...); 8952251883Speter 8953251883Speter/* 8954251883Speter** CAPI3REF: Write-Ahead Log Commit Hook 8955286510Speter** METHOD: sqlite3 8956251883Speter** 8957251883Speter** ^The [sqlite3_wal_hook()] function is used to register a callback that 8958282328Sbapt** is invoked each time data is committed to a database in wal mode. 8959251883Speter** 8960366076Scy** ^(The callback is invoked by SQLite after the commit has taken place and 8961366076Scy** the associated write-lock on the database released)^, so the implementation 8962251883Speter** may read, write or [checkpoint] the database as required. 8963251883Speter** 8964251883Speter** ^The first parameter passed to the callback function when it is invoked 8965251883Speter** is a copy of the third parameter passed to sqlite3_wal_hook() when 8966251883Speter** registering the callback. ^The second is a copy of the database handle. 8967251883Speter** ^The third parameter is the name of the database that was written to - 8968251883Speter** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter 8969251883Speter** is the number of pages currently in the write-ahead log file, 8970251883Speter** including those that were just committed. 8971251883Speter** 8972251883Speter** The callback function should normally return [SQLITE_OK]. ^If an error 8973251883Speter** code is returned, that error will propagate back up through the 8974251883Speter** SQLite code base to cause the statement that provoked the callback 8975251883Speter** to report an error, though the commit will have still occurred. If the 8976251883Speter** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value 8977251883Speter** that does not correspond to any valid SQLite error code, the results 8978251883Speter** are undefined. 8979251883Speter** 8980366076Scy** A single database handle may have at most a single write-ahead log callback 8981251883Speter** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any 8982251883Speter** previously registered write-ahead log callback. ^Note that the 8983251883Speter** [sqlite3_wal_autocheckpoint()] interface and the 8984251883Speter** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will 8985298161Sbapt** overwrite any prior [sqlite3_wal_hook()] settings. 8986251883Speter*/ 8987322444SpeterSQLITE_API void *sqlite3_wal_hook( 8988366076Scy sqlite3*, 8989251883Speter int(*)(void *,sqlite3*,const char*,int), 8990251883Speter void* 8991251883Speter); 8992251883Speter 8993251883Speter/* 8994251883Speter** CAPI3REF: Configure an auto-checkpoint 8995286510Speter** METHOD: sqlite3 8996251883Speter** 8997251883Speter** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around 8998251883Speter** [sqlite3_wal_hook()] that causes any database on [database connection] D 8999251883Speter** to automatically [checkpoint] 9000251883Speter** after committing a transaction if there are N or 9001366076Scy** more frames in the [write-ahead log] file. ^Passing zero or 9002251883Speter** a negative value as the nFrame parameter disables automatic 9003251883Speter** checkpoints entirely. 9004251883Speter** 9005251883Speter** ^The callback registered by this function replaces any existing callback 9006251883Speter** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback 9007251883Speter** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism 9008251883Speter** configured by this function. 9009251883Speter** 9010251883Speter** ^The [wal_autocheckpoint pragma] can be used to invoke this interface 9011251883Speter** from SQL. 9012251883Speter** 9013274884Sbapt** ^Checkpoints initiated by this mechanism are 9014274884Sbapt** [sqlite3_wal_checkpoint_v2|PASSIVE]. 9015274884Sbapt** 9016251883Speter** ^Every new [database connection] defaults to having the auto-checkpoint 9017251883Speter** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT] 9018251883Speter** pages. The use of this interface 9019251883Speter** is only necessary if the default setting is found to be suboptimal 9020251883Speter** for a particular application. 9021251883Speter*/ 9022322444SpeterSQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N); 9023251883Speter 9024251883Speter/* 9025251883Speter** CAPI3REF: Checkpoint a database 9026286510Speter** METHOD: sqlite3 9027251883Speter** 9028282328Sbapt** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to 9029282328Sbapt** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^ 9030251883Speter** 9031366076Scy** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the 9032282328Sbapt** [write-ahead log] for database X on [database connection] D to be 9033282328Sbapt** transferred into the database file and for the write-ahead log to 9034282328Sbapt** be reset. See the [checkpointing] documentation for addition 9035282328Sbapt** information. 9036251883Speter** 9037282328Sbapt** This interface used to be the only way to cause a checkpoint to 9038282328Sbapt** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()] 9039282328Sbapt** interface was added. This interface is retained for backwards 9040282328Sbapt** compatibility and as a convenience for applications that need to manually 9041282328Sbapt** start a callback but which do not need the full power (and corresponding 9042282328Sbapt** complication) of [sqlite3_wal_checkpoint_v2()]. 9043251883Speter*/ 9044322444SpeterSQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb); 9045251883Speter 9046251883Speter/* 9047251883Speter** CAPI3REF: Checkpoint a database 9048286510Speter** METHOD: sqlite3 9049251883Speter** 9050282328Sbapt** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint 9051282328Sbapt** operation on database X of [database connection] D in mode M. Status 9052282328Sbapt** information is written back into integers pointed to by L and C.)^ 9053282328Sbapt** ^(The M parameter must be a valid [checkpoint mode]:)^ 9054251883Speter** 9055251883Speter** <dl> 9056251883Speter** <dt>SQLITE_CHECKPOINT_PASSIVE<dd> 9057366076Scy** ^Checkpoint as many frames as possible without waiting for any database 9058366076Scy** readers or writers to finish, then sync the database file if all frames 9059282328Sbapt** in the log were checkpointed. ^The [busy-handler callback] 9060366076Scy** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode. 9061282328Sbapt** ^On the other hand, passive mode might leave the checkpoint unfinished 9062282328Sbapt** if there are concurrent readers or writers. 9063251883Speter** 9064251883Speter** <dt>SQLITE_CHECKPOINT_FULL<dd> 9065282328Sbapt** ^This mode blocks (it invokes the 9066274884Sbapt** [sqlite3_busy_handler|busy-handler callback]) until there is no 9067251883Speter** database writer and all readers are reading from the most recent database 9068282328Sbapt** snapshot. ^It then checkpoints all frames in the log file and syncs the 9069282328Sbapt** database file. ^This mode blocks new database writers while it is pending, 9070282328Sbapt** but new database readers are allowed to continue unimpeded. 9071251883Speter** 9072251883Speter** <dt>SQLITE_CHECKPOINT_RESTART<dd> 9073282328Sbapt** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition 9074366076Scy** that after checkpointing the log file it blocks (calls the 9075282328Sbapt** [busy-handler callback]) 9076366076Scy** until all readers are reading from the database file only. ^This ensures 9077282328Sbapt** that the next writer will restart the log file from the beginning. 9078282328Sbapt** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new 9079282328Sbapt** database writer attempts while it is pending, but does not impede readers. 9080282328Sbapt** 9081282328Sbapt** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd> 9082282328Sbapt** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the 9083282328Sbapt** addition that it also truncates the log file to zero bytes just prior 9084282328Sbapt** to a successful return. 9085251883Speter** </dl> 9086251883Speter** 9087282328Sbapt** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in 9088282328Sbapt** the log file or to -1 if the checkpoint could not run because 9089282328Sbapt** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not 9090282328Sbapt** NULL,then *pnCkpt is set to the total number of checkpointed frames in the 9091282328Sbapt** log file (including any that were already checkpointed before the function 9092282328Sbapt** was called) or to -1 if the checkpoint could not run due to an error or 9093282328Sbapt** because the database is not in WAL mode. ^Note that upon successful 9094282328Sbapt** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been 9095282328Sbapt** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero. 9096251883Speter** 9097282328Sbapt** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If 9098366076Scy** any other process is running a checkpoint operation at the same time, the 9099366076Scy** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a 9100251883Speter** busy-handler configured, it will not be invoked in this case. 9101251883Speter** 9102366076Scy** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the 9103282328Sbapt** exclusive "writer" lock on the database file. ^If the writer lock cannot be 9104282328Sbapt** obtained immediately, and a busy-handler is configured, it is invoked and 9105282328Sbapt** the writer lock retried until either the busy-handler returns 0 or the lock 9106282328Sbapt** is successfully obtained. ^The busy-handler is also invoked while waiting for 9107282328Sbapt** database readers as described above. ^If the busy-handler returns 0 before 9108251883Speter** the writer lock is obtained or while waiting for database readers, the 9109366076Scy** checkpoint operation proceeds from that point in the same way as 9110366076Scy** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible 9111282328Sbapt** without blocking any further. ^SQLITE_BUSY is returned in this case. 9112251883Speter** 9113282328Sbapt** ^If parameter zDb is NULL or points to a zero length string, then the 9114366076Scy** specified operation is attempted on all WAL databases [attached] to 9115282328Sbapt** [database connection] db. In this case the 9116366076Scy** values written to output parameters *pnLog and *pnCkpt are undefined. ^If 9117366076Scy** an SQLITE_BUSY error is encountered when processing one or more of the 9118366076Scy** attached WAL databases, the operation is still attempted on any remaining 9119366076Scy** attached databases and SQLITE_BUSY is returned at the end. ^If any other 9120366076Scy** error occurs while processing an attached database, processing is abandoned 9121366076Scy** and the error code is returned to the caller immediately. ^If no error 9122366076Scy** (SQLITE_BUSY or otherwise) is encountered while processing the attached 9123251883Speter** databases, SQLITE_OK is returned. 9124251883Speter** 9125282328Sbapt** ^If database zDb is the name of an attached database that is not in WAL 9126282328Sbapt** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If 9127251883Speter** zDb is not NULL (or a zero length string) and is not the name of any 9128251883Speter** attached database, SQLITE_ERROR is returned to the caller. 9129282328Sbapt** 9130282328Sbapt** ^Unless it returns SQLITE_MISUSE, 9131282328Sbapt** the sqlite3_wal_checkpoint_v2() interface 9132282328Sbapt** sets the error information that is queried by 9133282328Sbapt** [sqlite3_errcode()] and [sqlite3_errmsg()]. 9134282328Sbapt** 9135282328Sbapt** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface 9136282328Sbapt** from SQL. 9137251883Speter*/ 9138322444SpeterSQLITE_API int sqlite3_wal_checkpoint_v2( 9139251883Speter sqlite3 *db, /* Database handle */ 9140251883Speter const char *zDb, /* Name of attached database (or NULL) */ 9141251883Speter int eMode, /* SQLITE_CHECKPOINT_* value */ 9142251883Speter int *pnLog, /* OUT: Size of WAL log in frames */ 9143251883Speter int *pnCkpt /* OUT: Total number of frames checkpointed */ 9144251883Speter); 9145251883Speter 9146251883Speter/* 9147282328Sbapt** CAPI3REF: Checkpoint Mode Values 9148282328Sbapt** KEYWORDS: {checkpoint mode} 9149251883Speter** 9150282328Sbapt** These constants define all valid values for the "checkpoint mode" passed 9151282328Sbapt** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface. 9152282328Sbapt** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the 9153282328Sbapt** meaning of each of these checkpoint modes. 9154251883Speter*/ 9155282328Sbapt#define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */ 9156282328Sbapt#define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */ 9157282328Sbapt#define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for for readers */ 9158282328Sbapt#define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */ 9159251883Speter 9160251883Speter/* 9161251883Speter** CAPI3REF: Virtual Table Interface Configuration 9162251883Speter** 9163251883Speter** This function may be called by either the [xConnect] or [xCreate] method 9164251883Speter** of a [virtual table] implementation to configure 9165251883Speter** various facets of the virtual table interface. 9166251883Speter** 9167251883Speter** If this interface is invoked outside the context of an xConnect or 9168251883Speter** xCreate virtual table method then the behavior is undefined. 9169251883Speter** 9170361456Scy** In the call sqlite3_vtab_config(D,C,...) the D parameter is the 9171361456Scy** [database connection] in which the virtual table is being created and 9172361456Scy** which is passed in as the first argument to the [xConnect] or [xCreate] 9173361456Scy** method that is invoking sqlite3_vtab_config(). The C parameter is one 9174361456Scy** of the [virtual table configuration options]. The presence and meaning 9175361456Scy** of parameters after C depend on which [virtual table configuration option] 9176361456Scy** is used. 9177251883Speter*/ 9178322444SpeterSQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...); 9179251883Speter 9180251883Speter/* 9181251883Speter** CAPI3REF: Virtual Table Configuration Options 9182366076Scy** KEYWORDS: {virtual table configuration options} 9183361456Scy** KEYWORDS: {virtual table configuration option} 9184251883Speter** 9185251883Speter** These macros define the various options to the 9186251883Speter** [sqlite3_vtab_config()] interface that [virtual table] implementations 9187251883Speter** can use to customize and optimize their behavior. 9188251883Speter** 9189251883Speter** <dl> 9190342292Scy** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]] 9191361456Scy** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT</dt> 9192251883Speter** <dd>Calls of the form 9193251883Speter** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported, 9194251883Speter** where X is an integer. If X is zero, then the [virtual table] whose 9195251883Speter** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not 9196251883Speter** support constraints. In this configuration (which is the default) if 9197251883Speter** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire 9198251883Speter** statement is rolled back as if [ON CONFLICT | OR ABORT] had been 9199251883Speter** specified as part of the users SQL statement, regardless of the actual 9200251883Speter** ON CONFLICT mode specified. 9201251883Speter** 9202251883Speter** If X is non-zero, then the virtual table implementation guarantees 9203251883Speter** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before 9204251883Speter** any modifications to internal or persistent data structures have been made. 9205366076Scy** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite 9206251883Speter** is able to roll back a statement or database transaction, and abandon 9207366076Scy** or continue processing the current SQL statement as appropriate. 9208251883Speter** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns 9209251883Speter** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode 9210251883Speter** had been ABORT. 9211251883Speter** 9212251883Speter** Virtual table implementations that are required to handle OR REPLACE 9213366076Scy** must do so within the [xUpdate] method. If a call to the 9214366076Scy** [sqlite3_vtab_on_conflict()] function indicates that the current ON 9215366076Scy** CONFLICT policy is REPLACE, the virtual table implementation should 9216251883Speter** silently replace the appropriate rows within the xUpdate callback and 9217251883Speter** return SQLITE_OK. Or, if this is not possible, it may return 9218366076Scy** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT 9219251883Speter** constraint handling. 9220361456Scy** </dd> 9221361456Scy** 9222361456Scy** [[SQLITE_VTAB_DIRECTONLY]]<dt>SQLITE_VTAB_DIRECTONLY</dt> 9223361456Scy** <dd>Calls of the form 9224361456Scy** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the 9225361456Scy** the [xConnect] or [xCreate] methods of a [virtual table] implmentation 9226361456Scy** prohibits that virtual table from being used from within triggers and 9227361456Scy** views. 9228361456Scy** </dd> 9229361456Scy** 9230361456Scy** [[SQLITE_VTAB_INNOCUOUS]]<dt>SQLITE_VTAB_INNOCUOUS</dt> 9231361456Scy** <dd>Calls of the form 9232361456Scy** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the 9233361456Scy** the [xConnect] or [xCreate] methods of a [virtual table] implmentation 9234361456Scy** identify that virtual table as being safe to use from within triggers 9235361456Scy** and views. Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the 9236361456Scy** virtual table can do no serious harm even if it is controlled by a 9237361456Scy** malicious hacker. Developers should avoid setting the SQLITE_VTAB_INNOCUOUS 9238361456Scy** flag unless absolutely necessary. 9239361456Scy** </dd> 9240251883Speter** </dl> 9241251883Speter*/ 9242251883Speter#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1 9243361456Scy#define SQLITE_VTAB_INNOCUOUS 2 9244361456Scy#define SQLITE_VTAB_DIRECTONLY 3 9245251883Speter 9246251883Speter/* 9247251883Speter** CAPI3REF: Determine The Virtual Table Conflict Policy 9248251883Speter** 9249251883Speter** This function may only be called from within a call to the [xUpdate] method 9250251883Speter** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The 9251251883Speter** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL], 9252251883Speter** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode 9253251883Speter** of the SQL statement that triggered the call to the [xUpdate] method of the 9254251883Speter** [virtual table]. 9255251883Speter*/ 9256322444SpeterSQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *); 9257251883Speter 9258251883Speter/* 9259342292Scy** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE 9260342292Scy** 9261342292Scy** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn] 9262369950Scy** method of a [virtual table], then it might return true if the 9263342292Scy** column is being fetched as part of an UPDATE operation during which the 9264369950Scy** column value will not change. The virtual table implementation can use 9265369950Scy** this hint as permission to substitute a return value that is less 9266369950Scy** expensive to compute and that the corresponding 9267342292Scy** [xUpdate] method understands as a "no-change" value. 9268342292Scy** 9269342292Scy** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that 9270342292Scy** the column is not changed by the UPDATE statement, then the xColumn 9271342292Scy** method can optionally return without setting a result, without calling 9272342292Scy** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces]. 9273342292Scy** In that case, [sqlite3_value_nochange(X)] will return true for the 9274342292Scy** same column in the [xUpdate] method. 9275369950Scy** 9276369950Scy** The sqlite3_vtab_nochange() routine is an optimization. Virtual table 9277369950Scy** implementations should continue to give a correct answer even if the 9278369950Scy** sqlite3_vtab_nochange() interface were to always return false. In the 9279369950Scy** current implementation, the sqlite3_vtab_nochange() interface does always 9280369950Scy** returns false for the enhanced [UPDATE FROM] statement. 9281342292Scy*/ 9282342292ScySQLITE_API int sqlite3_vtab_nochange(sqlite3_context*); 9283342292Scy 9284342292Scy/* 9285342292Scy** CAPI3REF: Determine The Collation For a Virtual Table Constraint 9286342292Scy** 9287342292Scy** This function may only be called from within a call to the [xBestIndex] 9288366076Scy** method of a [virtual table]. 9289342292Scy** 9290342292Scy** The first argument must be the sqlite3_index_info object that is the 9291342292Scy** first parameter to the xBestIndex() method. The second argument must be 9292342292Scy** an index into the aConstraint[] array belonging to the sqlite3_index_info 9293366076Scy** structure passed to xBestIndex. This function returns a pointer to a buffer 9294342292Scy** containing the name of the collation sequence for the corresponding 9295342292Scy** constraint. 9296342292Scy*/ 9297342292ScySQLITE_API SQLITE_EXPERIMENTAL const char *sqlite3_vtab_collation(sqlite3_index_info*,int); 9298342292Scy 9299342292Scy/* 9300251883Speter** CAPI3REF: Conflict resolution modes 9301274884Sbapt** KEYWORDS: {conflict resolution mode} 9302251883Speter** 9303251883Speter** These constants are returned by [sqlite3_vtab_on_conflict()] to 9304251883Speter** inform a [virtual table] implementation what the [ON CONFLICT] mode 9305251883Speter** is for the SQL statement being evaluated. 9306251883Speter** 9307251883Speter** Note that the [SQLITE_IGNORE] constant is also used as a potential 9308251883Speter** return value from the [sqlite3_set_authorizer()] callback and that 9309251883Speter** [SQLITE_ABORT] is also a [result code]. 9310251883Speter*/ 9311251883Speter#define SQLITE_ROLLBACK 1 9312251883Speter/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */ 9313251883Speter#define SQLITE_FAIL 3 9314251883Speter/* #define SQLITE_ABORT 4 // Also an error code */ 9315251883Speter#define SQLITE_REPLACE 5 9316251883Speter 9317282328Sbapt/* 9318282328Sbapt** CAPI3REF: Prepared Statement Scan Status Opcodes 9319282328Sbapt** KEYWORDS: {scanstatus options} 9320282328Sbapt** 9321282328Sbapt** The following constants can be used for the T parameter to the 9322282328Sbapt** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a 9323282328Sbapt** different metric for sqlite3_stmt_scanstatus() to return. 9324282328Sbapt** 9325282328Sbapt** When the value returned to V is a string, space to hold that string is 9326282328Sbapt** managed by the prepared statement S and will be automatically freed when 9327282328Sbapt** S is finalized. 9328282328Sbapt** 9329282328Sbapt** <dl> 9330282328Sbapt** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt> 9331361456Scy** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be 9332282328Sbapt** set to the total number of times that the X-th loop has run.</dd> 9333282328Sbapt** 9334282328Sbapt** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt> 9335361456Scy** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be set 9336282328Sbapt** to the total number of rows examined by all iterations of the X-th loop.</dd> 9337282328Sbapt** 9338282328Sbapt** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt> 9339361456Scy** <dd>^The "double" variable pointed to by the V parameter will be set to the 9340282328Sbapt** query planner's estimate for the average number of rows output from each 9341282328Sbapt** iteration of the X-th loop. If the query planner's estimates was accurate, 9342282328Sbapt** then this value will approximate the quotient NVISIT/NLOOP and the 9343282328Sbapt** product of this value for all prior loops with the same SELECTID will 9344282328Sbapt** be the NLOOP value for the current loop. 9345282328Sbapt** 9346282328Sbapt** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt> 9347361456Scy** <dd>^The "const char *" variable pointed to by the V parameter will be set 9348282328Sbapt** to a zero-terminated UTF-8 string containing the name of the index or table 9349282328Sbapt** used for the X-th loop. 9350282328Sbapt** 9351282328Sbapt** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt> 9352361456Scy** <dd>^The "const char *" variable pointed to by the V parameter will be set 9353282328Sbapt** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN] 9354282328Sbapt** description for the X-th loop. 9355282328Sbapt** 9356282328Sbapt** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt> 9357361456Scy** <dd>^The "int" variable pointed to by the V parameter will be set to the 9358282328Sbapt** "select-id" for the X-th loop. The select-id identifies which query or 9359282328Sbapt** subquery the loop is part of. The main query has a select-id of zero. 9360282328Sbapt** The select-id is the same value as is output in the first column 9361282328Sbapt** of an [EXPLAIN QUERY PLAN] query. 9362282328Sbapt** </dl> 9363282328Sbapt*/ 9364282328Sbapt#define SQLITE_SCANSTAT_NLOOP 0 9365282328Sbapt#define SQLITE_SCANSTAT_NVISIT 1 9366282328Sbapt#define SQLITE_SCANSTAT_EST 2 9367282328Sbapt#define SQLITE_SCANSTAT_NAME 3 9368282328Sbapt#define SQLITE_SCANSTAT_EXPLAIN 4 9369282328Sbapt#define SQLITE_SCANSTAT_SELECTID 5 9370251883Speter 9371282328Sbapt/* 9372282328Sbapt** CAPI3REF: Prepared Statement Scan Status 9373286510Speter** METHOD: sqlite3_stmt 9374282328Sbapt** 9375282328Sbapt** This interface returns information about the predicted and measured 9376282328Sbapt** performance for pStmt. Advanced applications can use this 9377282328Sbapt** interface to compare the predicted and the measured performance and 9378282328Sbapt** issue warnings and/or rerun [ANALYZE] if discrepancies are found. 9379282328Sbapt** 9380282328Sbapt** Since this interface is expected to be rarely used, it is only 9381282328Sbapt** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS] 9382282328Sbapt** compile-time option. 9383282328Sbapt** 9384282328Sbapt** The "iScanStatusOp" parameter determines which status information to return. 9385282328Sbapt** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior 9386282328Sbapt** of this interface is undefined. 9387282328Sbapt** ^The requested measurement is written into a variable pointed to by 9388282328Sbapt** the "pOut" parameter. 9389282328Sbapt** Parameter "idx" identifies the specific loop to retrieve statistics for. 9390282328Sbapt** Loops are numbered starting from zero. ^If idx is out of range - less than 9391282328Sbapt** zero or greater than or equal to the total number of loops used to implement 9392282328Sbapt** the statement - a non-zero value is returned and the variable that pOut 9393282328Sbapt** points to is unchanged. 9394282328Sbapt** 9395282328Sbapt** ^Statistics might not be available for all loops in all statements. ^In cases 9396282328Sbapt** where there exist loops with no available statistics, this function behaves 9397282328Sbapt** as if the loop did not exist - it returns non-zero and leave the variable 9398282328Sbapt** that pOut points to unchanged. 9399282328Sbapt** 9400282328Sbapt** See also: [sqlite3_stmt_scanstatus_reset()] 9401282328Sbapt*/ 9402322444SpeterSQLITE_API int sqlite3_stmt_scanstatus( 9403282328Sbapt sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ 9404282328Sbapt int idx, /* Index of loop to report on */ 9405282328Sbapt int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ 9406282328Sbapt void *pOut /* Result written here */ 9407366076Scy); 9408251883Speter 9409251883Speter/* 9410282328Sbapt** CAPI3REF: Zero Scan-Status Counters 9411286510Speter** METHOD: sqlite3_stmt 9412282328Sbapt** 9413282328Sbapt** ^Zero all [sqlite3_stmt_scanstatus()] related event counters. 9414282328Sbapt** 9415282328Sbapt** This API is only available if the library is built with pre-processor 9416282328Sbapt** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined. 9417282328Sbapt*/ 9418322444SpeterSQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*); 9419282328Sbapt 9420298161Sbapt/* 9421298161Sbapt** CAPI3REF: Flush caches to disk mid-transaction 9422369950Scy** METHOD: sqlite3 9423298161Sbapt** 9424298161Sbapt** ^If a write-transaction is open on [database connection] D when the 9425298161Sbapt** [sqlite3_db_cacheflush(D)] interface invoked, any dirty 9426366076Scy** pages in the pager-cache that are not currently in use are written out 9427298161Sbapt** to disk. A dirty page may be in use if a database cursor created by an 9428298161Sbapt** active SQL statement is reading from it, or if it is page 1 of a database 9429298161Sbapt** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)] 9430298161Sbapt** interface flushes caches for all schemas - "main", "temp", and 9431298161Sbapt** any [attached] databases. 9432298161Sbapt** 9433366076Scy** ^If this function needs to obtain extra database locks before dirty pages 9434366076Scy** can be flushed to disk, it does so. ^If those locks cannot be obtained 9435298161Sbapt** immediately and there is a busy-handler callback configured, it is invoked 9436298161Sbapt** in the usual manner. ^If the required lock still cannot be obtained, then 9437298161Sbapt** the database is skipped and an attempt made to flush any dirty pages 9438298161Sbapt** belonging to the next (if any) database. ^If any databases are skipped 9439298161Sbapt** because locks cannot be obtained, but no other error occurs, this 9440298161Sbapt** function returns SQLITE_BUSY. 9441298161Sbapt** 9442298161Sbapt** ^If any other error occurs while flushing dirty pages to disk (for 9443298161Sbapt** example an IO error or out-of-memory condition), then processing is 9444298161Sbapt** abandoned and an SQLite [error code] is returned to the caller immediately. 9445298161Sbapt** 9446298161Sbapt** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK. 9447298161Sbapt** 9448298161Sbapt** ^This function does not set the database handle error code or message 9449298161Sbapt** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions. 9450298161Sbapt*/ 9451322444SpeterSQLITE_API int sqlite3_db_cacheflush(sqlite3*); 9452282328Sbapt 9453282328Sbapt/* 9454305002Scy** CAPI3REF: The pre-update hook. 9455369950Scy** METHOD: sqlite3 9456305002Scy** 9457305002Scy** ^These interfaces are only available if SQLite is compiled using the 9458305002Scy** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option. 9459305002Scy** 9460305002Scy** ^The [sqlite3_preupdate_hook()] interface registers a callback function 9461305002Scy** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation 9462322444Speter** on a database table. 9463305002Scy** ^At most one preupdate hook may be registered at a time on a single 9464305002Scy** [database connection]; each call to [sqlite3_preupdate_hook()] overrides 9465305002Scy** the previous setting. 9466305002Scy** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()] 9467305002Scy** with a NULL pointer as the second parameter. 9468305002Scy** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as 9469305002Scy** the first parameter to callbacks. 9470305002Scy** 9471322444Speter** ^The preupdate hook only fires for changes to real database tables; the 9472322444Speter** preupdate hook is not invoked for changes to [virtual tables] or to 9473366076Scy** system tables like sqlite_sequence or sqlite_stat1. 9474305002Scy** 9475305002Scy** ^The second parameter to the preupdate callback is a pointer to 9476305002Scy** the [database connection] that registered the preupdate hook. 9477305002Scy** ^The third parameter to the preupdate callback is one of the constants 9478305002Scy** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the 9479305002Scy** kind of update operation that is about to occur. 9480305002Scy** ^(The fourth parameter to the preupdate callback is the name of the 9481305002Scy** database within the database connection that is being modified. This 9482366076Scy** will be "main" for the main database or "temp" for TEMP tables or 9483305002Scy** the name given after the AS keyword in the [ATTACH] statement for attached 9484305002Scy** databases.)^ 9485305002Scy** ^The fifth parameter to the preupdate callback is the name of the 9486305002Scy** table that is being modified. 9487305002Scy** 9488322444Speter** For an UPDATE or DELETE operation on a [rowid table], the sixth 9489366076Scy** parameter passed to the preupdate callback is the initial [rowid] of the 9490322444Speter** row being modified or deleted. For an INSERT operation on a rowid table, 9491366076Scy** or any operation on a WITHOUT ROWID table, the value of the sixth 9492322444Speter** parameter is undefined. For an INSERT or UPDATE on a rowid table the 9493322444Speter** seventh parameter is the final rowid value of the row being inserted 9494322444Speter** or updated. The value of the seventh parameter passed to the callback 9495322444Speter** function is not defined for operations on WITHOUT ROWID tables, or for 9496369950Scy** DELETE operations on rowid tables. 9497322444Speter** 9498305002Scy** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()], 9499305002Scy** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces 9500305002Scy** provide additional information about a preupdate event. These routines 9501305002Scy** may only be called from within a preupdate callback. Invoking any of 9502305002Scy** these routines from outside of a preupdate callback or with a 9503305002Scy** [database connection] pointer that is different from the one supplied 9504305002Scy** to the preupdate callback results in undefined and probably undesirable 9505305002Scy** behavior. 9506305002Scy** 9507305002Scy** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns 9508305002Scy** in the row that is being inserted, updated, or deleted. 9509305002Scy** 9510305002Scy** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to 9511305002Scy** a [protected sqlite3_value] that contains the value of the Nth column of 9512305002Scy** the table row before it is updated. The N parameter must be between 0 9513305002Scy** and one less than the number of columns or the behavior will be 9514305002Scy** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE 9515305002Scy** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the 9516305002Scy** behavior is undefined. The [sqlite3_value] that P points to 9517305002Scy** will be destroyed when the preupdate callback returns. 9518305002Scy** 9519305002Scy** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to 9520305002Scy** a [protected sqlite3_value] that contains the value of the Nth column of 9521305002Scy** the table row after it is updated. The N parameter must be between 0 9522305002Scy** and one less than the number of columns or the behavior will be 9523305002Scy** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE 9524305002Scy** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the 9525305002Scy** behavior is undefined. The [sqlite3_value] that P points to 9526305002Scy** will be destroyed when the preupdate callback returns. 9527305002Scy** 9528305002Scy** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate 9529305002Scy** callback was invoked as a result of a direct insert, update, or delete 9530366076Scy** operation; or 1 for inserts, updates, or deletes invoked by top-level 9531305002Scy** triggers; or 2 for changes resulting from triggers called by top-level 9532305002Scy** triggers; and so forth. 9533305002Scy** 9534305002Scy** See also: [sqlite3_update_hook()] 9535305002Scy*/ 9536322444Speter#if defined(SQLITE_ENABLE_PREUPDATE_HOOK) 9537322444SpeterSQLITE_API void *sqlite3_preupdate_hook( 9538305002Scy sqlite3 *db, 9539305002Scy void(*xPreUpdate)( 9540305002Scy void *pCtx, /* Copy of third arg to preupdate_hook() */ 9541305002Scy sqlite3 *db, /* Database handle */ 9542305002Scy int op, /* SQLITE_UPDATE, DELETE or INSERT */ 9543305002Scy char const *zDb, /* Database name */ 9544305002Scy char const *zName, /* Table name */ 9545305002Scy sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */ 9546305002Scy sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */ 9547305002Scy ), 9548305002Scy void* 9549305002Scy); 9550322444SpeterSQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **); 9551322444SpeterSQLITE_API int sqlite3_preupdate_count(sqlite3 *); 9552322444SpeterSQLITE_API int sqlite3_preupdate_depth(sqlite3 *); 9553322444SpeterSQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **); 9554322444Speter#endif 9555305002Scy 9556305002Scy/* 9557298161Sbapt** CAPI3REF: Low-level system error code 9558369950Scy** METHOD: sqlite3 9559298161Sbapt** 9560298161Sbapt** ^Attempt to return the underlying operating system error code or error 9561305002Scy** number that caused the most recent I/O error or failure to open a file. 9562298161Sbapt** The return value is OS-dependent. For example, on unix systems, after 9563298161Sbapt** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be 9564298161Sbapt** called to get back the underlying "errno" that caused the problem, such 9565366076Scy** as ENOSPC, EAUTH, EISDIR, and so forth. 9566298161Sbapt*/ 9567322444SpeterSQLITE_API int sqlite3_system_errno(sqlite3*); 9568298161Sbapt 9569298161Sbapt/* 9570298161Sbapt** CAPI3REF: Database Snapshot 9571322444Speter** KEYWORDS: {snapshot} {sqlite3_snapshot} 9572298161Sbapt** 9573298161Sbapt** An instance of the snapshot object records the state of a [WAL mode] 9574298161Sbapt** database for some specific point in history. 9575298161Sbapt** 9576298161Sbapt** In [WAL mode], multiple [database connections] that are open on the 9577298161Sbapt** same database file can each be reading a different historical version 9578298161Sbapt** of the database file. When a [database connection] begins a read 9579298161Sbapt** transaction, that connection sees an unchanging copy of the database 9580298161Sbapt** as it existed for the point in time when the transaction first started. 9581298161Sbapt** Subsequent changes to the database from other connections are not seen 9582298161Sbapt** by the reader until a new read transaction is started. 9583298161Sbapt** 9584298161Sbapt** The sqlite3_snapshot object records state information about an historical 9585298161Sbapt** version of the database file so that it is possible to later open a new read 9586298161Sbapt** transaction that sees that historical version of the database rather than 9587298161Sbapt** the most recent version. 9588298161Sbapt*/ 9589322444Spetertypedef struct sqlite3_snapshot { 9590322444Speter unsigned char hidden[48]; 9591322444Speter} sqlite3_snapshot; 9592298161Sbapt 9593298161Sbapt/* 9594298161Sbapt** CAPI3REF: Record A Database Snapshot 9595342292Scy** CONSTRUCTOR: sqlite3_snapshot 9596298161Sbapt** 9597298161Sbapt** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a 9598298161Sbapt** new [sqlite3_snapshot] object that records the current state of 9599298161Sbapt** schema S in database connection D. ^On success, the 9600298161Sbapt** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly 9601298161Sbapt** created [sqlite3_snapshot] object into *P and returns SQLITE_OK. 9602322444Speter** If there is not already a read-transaction open on schema S when 9603366076Scy** this function is called, one is opened automatically. 9604298161Sbapt** 9605322444Speter** The following must be true for this function to succeed. If any of 9606322444Speter** the following statements are false when sqlite3_snapshot_get() is 9607322444Speter** called, SQLITE_ERROR is returned. The final value of *P is undefined 9608366076Scy** in this case. 9609322444Speter** 9610322444Speter** <ul> 9611342292Scy** <li> The database handle must not be in [autocommit mode]. 9612322444Speter** 9613322444Speter** <li> Schema S of [database connection] D must be a [WAL mode] database. 9614322444Speter** 9615322444Speter** <li> There must not be a write transaction open on schema S of database 9616322444Speter** connection D. 9617322444Speter** 9618322444Speter** <li> One or more transactions must have been written to the current wal 9619322444Speter** file since it was created on disk (by any connection). This means 9620366076Scy** that a snapshot cannot be taken on a wal mode database with no wal 9621322444Speter** file immediately after it is first opened. At least one transaction 9622322444Speter** must be written to it first. 9623322444Speter** </ul> 9624322444Speter** 9625322444Speter** This function may also return SQLITE_NOMEM. If it is called with the 9626366076Scy** database handle in autocommit mode but fails for some other reason, 9627322444Speter** whether or not a read transaction is opened on schema S is undefined. 9628322444Speter** 9629298161Sbapt** The [sqlite3_snapshot] object returned from a successful call to 9630298161Sbapt** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()] 9631298161Sbapt** to avoid a memory leak. 9632298161Sbapt** 9633298161Sbapt** The [sqlite3_snapshot_get()] interface is only available when the 9634342292Scy** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 9635298161Sbapt*/ 9636322444SpeterSQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get( 9637298161Sbapt sqlite3 *db, 9638298161Sbapt const char *zSchema, 9639298161Sbapt sqlite3_snapshot **ppSnapshot 9640298161Sbapt); 9641298161Sbapt 9642298161Sbapt/* 9643298161Sbapt** CAPI3REF: Start a read transaction on an historical snapshot 9644342292Scy** METHOD: sqlite3_snapshot 9645298161Sbapt** 9646366076Scy** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read 9647366076Scy** transaction or upgrades an existing one for schema S of 9648366076Scy** [database connection] D such that the read transaction refers to 9649366076Scy** historical [snapshot] P, rather than the most recent change to the 9650366076Scy** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK 9651342292Scy** on success or an appropriate [error code] if it fails. 9652298161Sbapt** 9653366076Scy** ^In order to succeed, the database connection must not be in 9654342292Scy** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there 9655342292Scy** is already a read transaction open on schema S, then the database handle 9656342292Scy** must have no active statements (SELECT statements that have been passed 9657366076Scy** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()). 9658342292Scy** SQLITE_ERROR is returned if either of these conditions is violated, or 9659342292Scy** if schema S does not exist, or if the snapshot object is invalid. 9660342292Scy** 9661342292Scy** ^A call to sqlite3_snapshot_open() will fail to open if the specified 9662366076Scy** snapshot has been overwritten by a [checkpoint]. In this case 9663342292Scy** SQLITE_ERROR_SNAPSHOT is returned. 9664342292Scy** 9665366076Scy** If there is already a read transaction open when this function is 9666342292Scy** invoked, then the same read transaction remains open (on the same 9667342292Scy** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT 9668342292Scy** is returned. If another error code - for example SQLITE_PROTOCOL or an 9669342292Scy** SQLITE_IOERR error code - is returned, then the final state of the 9670366076Scy** read transaction is undefined. If SQLITE_OK is returned, then the 9671342292Scy** read transaction is now open on database snapshot P. 9672342292Scy** 9673305002Scy** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the 9674305002Scy** database connection D does not know that the database file for 9675305002Scy** schema S is in [WAL mode]. A database connection might not know 9676305002Scy** that the database file is in [WAL mode] if there has been no prior 9677366076Scy** I/O on that database connection, or if the database entered [WAL mode] 9678305002Scy** after the most recent I/O on the database connection.)^ 9679305002Scy** (Hint: Run "[PRAGMA application_id]" against a newly opened 9680298161Sbapt** database connection in order to make it ready to use snapshots.) 9681298161Sbapt** 9682298161Sbapt** The [sqlite3_snapshot_open()] interface is only available when the 9683342292Scy** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 9684298161Sbapt*/ 9685322444SpeterSQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open( 9686298161Sbapt sqlite3 *db, 9687298161Sbapt const char *zSchema, 9688298161Sbapt sqlite3_snapshot *pSnapshot 9689298161Sbapt); 9690298161Sbapt 9691298161Sbapt/* 9692298161Sbapt** CAPI3REF: Destroy a snapshot 9693342292Scy** DESTRUCTOR: sqlite3_snapshot 9694298161Sbapt** 9695298161Sbapt** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P. 9696298161Sbapt** The application must eventually free every [sqlite3_snapshot] object 9697298161Sbapt** using this routine to avoid a memory leak. 9698298161Sbapt** 9699298161Sbapt** The [sqlite3_snapshot_free()] interface is only available when the 9700342292Scy** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 9701298161Sbapt*/ 9702322444SpeterSQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*); 9703298161Sbapt 9704298161Sbapt/* 9705305002Scy** CAPI3REF: Compare the ages of two snapshot handles. 9706342292Scy** METHOD: sqlite3_snapshot 9707305002Scy** 9708305002Scy** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages 9709366076Scy** of two valid snapshot handles. 9710305002Scy** 9711366076Scy** If the two snapshot handles are not associated with the same database 9712366076Scy** file, the result of the comparison is undefined. 9713305002Scy** 9714305002Scy** Additionally, the result of the comparison is only valid if both of the 9715305002Scy** snapshot handles were obtained by calling sqlite3_snapshot_get() since the 9716305002Scy** last time the wal file was deleted. The wal file is deleted when the 9717305002Scy** database is changed back to rollback mode or when the number of database 9718366076Scy** clients drops to zero. If either snapshot handle was obtained before the 9719366076Scy** wal file was last deleted, the value returned by this function 9720305002Scy** is undefined. 9721305002Scy** 9722305002Scy** Otherwise, this API returns a negative value if P1 refers to an older 9723305002Scy** snapshot than P2, zero if the two handles refer to the same database 9724305002Scy** snapshot, and a positive value if P1 is a newer snapshot than P2. 9725342292Scy** 9726342292Scy** This interface is only available if SQLite is compiled with the 9727342292Scy** [SQLITE_ENABLE_SNAPSHOT] option. 9728305002Scy*/ 9729322444SpeterSQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp( 9730305002Scy sqlite3_snapshot *p1, 9731305002Scy sqlite3_snapshot *p2 9732305002Scy); 9733305002Scy 9734305002Scy/* 9735322444Speter** CAPI3REF: Recover snapshots from a wal file 9736342292Scy** METHOD: sqlite3_snapshot 9737322444Speter** 9738342292Scy** If a [WAL file] remains on disk after all database connections close 9739342292Scy** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control] 9740342292Scy** or because the last process to have the database opened exited without 9741342292Scy** calling [sqlite3_close()]) and a new connection is subsequently opened 9742342292Scy** on that database and [WAL file], the [sqlite3_snapshot_open()] interface 9743342292Scy** will only be able to open the last transaction added to the WAL file 9744342292Scy** even though the WAL file contains other valid transactions. 9745322444Speter** 9746342292Scy** This function attempts to scan the WAL file associated with database zDb 9747322444Speter** of database handle db and make all valid snapshots available to 9748322444Speter** sqlite3_snapshot_open(). It is an error if there is already a read 9749342292Scy** transaction open on the database, or if the database is not a WAL mode 9750322444Speter** database. 9751322444Speter** 9752322444Speter** SQLITE_OK is returned if successful, or an SQLite error code otherwise. 9753342292Scy** 9754342292Scy** This interface is only available if SQLite is compiled with the 9755342292Scy** [SQLITE_ENABLE_SNAPSHOT] option. 9756322444Speter*/ 9757322444SpeterSQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb); 9758322444Speter 9759322444Speter/* 9760342292Scy** CAPI3REF: Serialize a database 9761342292Scy** 9762342292Scy** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory 9763342292Scy** that is a serialization of the S database on [database connection] D. 9764342292Scy** If P is not a NULL pointer, then the size of the database in bytes 9765342292Scy** is written into *P. 9766342292Scy** 9767342292Scy** For an ordinary on-disk database file, the serialization is just a 9768342292Scy** copy of the disk file. For an in-memory database or a "TEMP" database, 9769342292Scy** the serialization is the same sequence of bytes which would be written 9770342292Scy** to disk if that database where backed up to disk. 9771342292Scy** 9772342292Scy** The usual case is that sqlite3_serialize() copies the serialization of 9773342292Scy** the database into memory obtained from [sqlite3_malloc64()] and returns 9774342292Scy** a pointer to that memory. The caller is responsible for freeing the 9775342292Scy** returned value to avoid a memory leak. However, if the F argument 9776342292Scy** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations 9777342292Scy** are made, and the sqlite3_serialize() function will return a pointer 9778342292Scy** to the contiguous memory representation of the database that SQLite 9779342292Scy** is currently using for that database, or NULL if the no such contiguous 9780342292Scy** memory representation of the database exists. A contiguous memory 9781342292Scy** representation of the database will usually only exist if there has 9782342292Scy** been a prior call to [sqlite3_deserialize(D,S,...)] with the same 9783342292Scy** values of D and S. 9784366076Scy** The size of the database is written into *P even if the 9785342292Scy** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy 9786342292Scy** of the database exists. 9787342292Scy** 9788342292Scy** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the 9789342292Scy** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory 9790342292Scy** allocation error occurs. 9791342292Scy** 9792342292Scy** This interface is only available if SQLite is compiled with the 9793342292Scy** [SQLITE_ENABLE_DESERIALIZE] option. 9794342292Scy*/ 9795342292ScySQLITE_API unsigned char *sqlite3_serialize( 9796342292Scy sqlite3 *db, /* The database connection */ 9797342292Scy const char *zSchema, /* Which DB to serialize. ex: "main", "temp", ... */ 9798342292Scy sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */ 9799342292Scy unsigned int mFlags /* Zero or more SQLITE_SERIALIZE_* flags */ 9800342292Scy); 9801342292Scy 9802342292Scy/* 9803342292Scy** CAPI3REF: Flags for sqlite3_serialize 9804342292Scy** 9805342292Scy** Zero or more of the following constants can be OR-ed together for 9806342292Scy** the F argument to [sqlite3_serialize(D,S,P,F)]. 9807342292Scy** 9808342292Scy** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return 9809342292Scy** a pointer to contiguous in-memory database that it is currently using, 9810342292Scy** without making a copy of the database. If SQLite is not currently using 9811342292Scy** a contiguous in-memory database, then this option causes 9812342292Scy** [sqlite3_serialize()] to return a NULL pointer. SQLite will only be 9813342292Scy** using a contiguous in-memory database if it has been initialized by a 9814342292Scy** prior call to [sqlite3_deserialize()]. 9815342292Scy*/ 9816342292Scy#define SQLITE_SERIALIZE_NOCOPY 0x001 /* Do no memory allocations */ 9817342292Scy 9818342292Scy/* 9819342292Scy** CAPI3REF: Deserialize a database 9820342292Scy** 9821366076Scy** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the 9822342292Scy** [database connection] D to disconnect from database S and then 9823342292Scy** reopen S as an in-memory database based on the serialization contained 9824342292Scy** in P. The serialized database P is N bytes in size. M is the size of 9825342292Scy** the buffer P, which might be larger than N. If M is larger than N, and 9826342292Scy** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is 9827342292Scy** permitted to add content to the in-memory database as long as the total 9828342292Scy** size does not exceed M bytes. 9829342292Scy** 9830342292Scy** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will 9831342292Scy** invoke sqlite3_free() on the serialization buffer when the database 9832342292Scy** connection closes. If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then 9833342292Scy** SQLite will try to increase the buffer size using sqlite3_realloc64() 9834342292Scy** if writes on the database cause it to grow larger than M bytes. 9835342292Scy** 9836342292Scy** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the 9837342292Scy** database is currently in a read transaction or is involved in a backup 9838342292Scy** operation. 9839342292Scy** 9840366076Scy** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the 9841342292Scy** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then 9842342292Scy** [sqlite3_free()] is invoked on argument P prior to returning. 9843342292Scy** 9844342292Scy** This interface is only available if SQLite is compiled with the 9845342292Scy** [SQLITE_ENABLE_DESERIALIZE] option. 9846342292Scy*/ 9847342292ScySQLITE_API int sqlite3_deserialize( 9848342292Scy sqlite3 *db, /* The database connection */ 9849342292Scy const char *zSchema, /* Which DB to reopen with the deserialization */ 9850342292Scy unsigned char *pData, /* The serialized database content */ 9851342292Scy sqlite3_int64 szDb, /* Number bytes in the deserialization */ 9852342292Scy sqlite3_int64 szBuf, /* Total size of buffer pData[] */ 9853342292Scy unsigned mFlags /* Zero or more SQLITE_DESERIALIZE_* flags */ 9854342292Scy); 9855342292Scy 9856342292Scy/* 9857342292Scy** CAPI3REF: Flags for sqlite3_deserialize() 9858342292Scy** 9859342292Scy** The following are allowed values for 6th argument (the F argument) to 9860342292Scy** the [sqlite3_deserialize(D,S,P,N,M,F)] interface. 9861342292Scy** 9862342292Scy** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization 9863342292Scy** in the P argument is held in memory obtained from [sqlite3_malloc64()] 9864342292Scy** and that SQLite should take ownership of this memory and automatically 9865342292Scy** free it when it has finished using it. Without this flag, the caller 9866342292Scy** is responsible for freeing any dynamically allocated memory. 9867342292Scy** 9868342292Scy** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to 9869342292Scy** grow the size of the database using calls to [sqlite3_realloc64()]. This 9870342292Scy** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used. 9871342292Scy** Without this flag, the deserialized database cannot increase in size beyond 9872342292Scy** the number of bytes specified by the M parameter. 9873342292Scy** 9874342292Scy** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database 9875342292Scy** should be treated as read-only. 9876342292Scy*/ 9877342292Scy#define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */ 9878342292Scy#define SQLITE_DESERIALIZE_RESIZEABLE 2 /* Resize using sqlite3_realloc64() */ 9879342292Scy#define SQLITE_DESERIALIZE_READONLY 4 /* Database is read-only */ 9880342292Scy 9881342292Scy/* 9882251883Speter** Undo the hack that converts floating point types to integer for 9883251883Speter** builds on processors without floating point support. 9884251883Speter*/ 9885251883Speter#ifdef SQLITE_OMIT_FLOATING_POINT 9886251883Speter# undef double 9887251883Speter#endif 9888251883Speter 9889251883Speter#ifdef __cplusplus 9890251883Speter} /* End of the 'extern "C"' block */ 9891251883Speter#endif 9892305002Scy#endif /* SQLITE3_H */ 9893251883Speter 9894305002Scy/******** Begin file sqlite3rtree.h *********/ 9895251883Speter/* 9896251883Speter** 2010 August 30 9897251883Speter** 9898251883Speter** The author disclaims copyright to this source code. In place of 9899251883Speter** a legal notice, here is a blessing: 9900251883Speter** 9901251883Speter** May you do good and not evil. 9902251883Speter** May you find forgiveness for yourself and forgive others. 9903251883Speter** May you share freely, never taking more than you give. 9904251883Speter** 9905251883Speter************************************************************************* 9906251883Speter*/ 9907251883Speter 9908251883Speter#ifndef _SQLITE3RTREE_H_ 9909251883Speter#define _SQLITE3RTREE_H_ 9910251883Speter 9911251883Speter 9912251883Speter#ifdef __cplusplus 9913251883Speterextern "C" { 9914251883Speter#endif 9915251883Speter 9916251883Spetertypedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry; 9917269851Spetertypedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info; 9918251883Speter 9919269851Speter/* The double-precision datatype used by RTree depends on the 9920269851Speter** SQLITE_RTREE_INT_ONLY compile-time option. 9921269851Speter*/ 9922269851Speter#ifdef SQLITE_RTREE_INT_ONLY 9923269851Speter typedef sqlite3_int64 sqlite3_rtree_dbl; 9924269851Speter#else 9925269851Speter typedef double sqlite3_rtree_dbl; 9926269851Speter#endif 9927269851Speter 9928251883Speter/* 9929251883Speter** Register a geometry callback named zGeom that can be used as part of an 9930251883Speter** R-Tree geometry query as follows: 9931251883Speter** 9932251883Speter** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...) 9933251883Speter*/ 9934322444SpeterSQLITE_API int sqlite3_rtree_geometry_callback( 9935251883Speter sqlite3 *db, 9936251883Speter const char *zGeom, 9937269851Speter int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*), 9938251883Speter void *pContext 9939251883Speter); 9940251883Speter 9941251883Speter 9942251883Speter/* 9943251883Speter** A pointer to a structure of the following type is passed as the first 9944251883Speter** argument to callbacks registered using rtree_geometry_callback(). 9945251883Speter*/ 9946251883Speterstruct sqlite3_rtree_geometry { 9947251883Speter void *pContext; /* Copy of pContext passed to s_r_g_c() */ 9948251883Speter int nParam; /* Size of array aParam[] */ 9949269851Speter sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */ 9950251883Speter void *pUser; /* Callback implementation user data */ 9951251883Speter void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */ 9952251883Speter}; 9953251883Speter 9954269851Speter/* 9955366076Scy** Register a 2nd-generation geometry callback named zScore that can be 9956269851Speter** used as part of an R-Tree geometry query as follows: 9957269851Speter** 9958269851Speter** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...) 9959269851Speter*/ 9960322444SpeterSQLITE_API int sqlite3_rtree_query_callback( 9961269851Speter sqlite3 *db, 9962269851Speter const char *zQueryFunc, 9963269851Speter int (*xQueryFunc)(sqlite3_rtree_query_info*), 9964269851Speter void *pContext, 9965269851Speter void (*xDestructor)(void*) 9966269851Speter); 9967251883Speter 9968269851Speter 9969269851Speter/* 9970366076Scy** A pointer to a structure of the following type is passed as the 9971269851Speter** argument to scored geometry callback registered using 9972269851Speter** sqlite3_rtree_query_callback(). 9973269851Speter** 9974269851Speter** Note that the first 5 fields of this structure are identical to 9975269851Speter** sqlite3_rtree_geometry. This structure is a subclass of 9976269851Speter** sqlite3_rtree_geometry. 9977269851Speter*/ 9978269851Speterstruct sqlite3_rtree_query_info { 9979269851Speter void *pContext; /* pContext from when function registered */ 9980269851Speter int nParam; /* Number of function parameters */ 9981269851Speter sqlite3_rtree_dbl *aParam; /* value of function parameters */ 9982269851Speter void *pUser; /* callback can use this, if desired */ 9983269851Speter void (*xDelUser)(void*); /* function to free pUser */ 9984269851Speter sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */ 9985269851Speter unsigned int *anQueue; /* Number of pending entries in the queue */ 9986269851Speter int nCoord; /* Number of coordinates */ 9987269851Speter int iLevel; /* Level of current node or entry */ 9988269851Speter int mxLevel; /* The largest iLevel value in the tree */ 9989269851Speter sqlite3_int64 iRowid; /* Rowid for current entry */ 9990269851Speter sqlite3_rtree_dbl rParentScore; /* Score of parent node */ 9991269851Speter int eParentWithin; /* Visibility of parent node */ 9992342292Scy int eWithin; /* OUT: Visibility */ 9993269851Speter sqlite3_rtree_dbl rScore; /* OUT: Write the score here */ 9994286510Speter /* The following fields are only available in 3.8.11 and later */ 9995286510Speter sqlite3_value **apSqlParam; /* Original SQL values of parameters */ 9996269851Speter}; 9997269851Speter 9998269851Speter/* 9999269851Speter** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin. 10000269851Speter*/ 10001269851Speter#define NOT_WITHIN 0 /* Object completely outside of query region */ 10002269851Speter#define PARTLY_WITHIN 1 /* Object partially overlaps query region */ 10003269851Speter#define FULLY_WITHIN 2 /* Object fully contained within query region */ 10004269851Speter 10005269851Speter 10006251883Speter#ifdef __cplusplus 10007251883Speter} /* end of the 'extern "C"' block */ 10008251883Speter#endif 10009251883Speter 10010251883Speter#endif /* ifndef _SQLITE3RTREE_H_ */ 10011251883Speter 10012305002Scy/******** End of sqlite3rtree.h *********/ 10013305002Scy/******** Begin file sqlite3session.h *********/ 10014305002Scy 10015305002Scy#if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) 10016305002Scy#define __SQLITESESSION_H_ 1 10017305002Scy 10018298161Sbapt/* 10019305002Scy** Make sure we can call this stuff from C++. 10020305002Scy*/ 10021305002Scy#ifdef __cplusplus 10022305002Scyextern "C" { 10023305002Scy#endif 10024305002Scy 10025305002Scy 10026305002Scy/* 10027305002Scy** CAPI3REF: Session Object Handle 10028342292Scy** 10029342292Scy** An instance of this object is a [session] that can be used to 10030342292Scy** record changes to a database. 10031305002Scy*/ 10032305002Scytypedef struct sqlite3_session sqlite3_session; 10033305002Scy 10034305002Scy/* 10035305002Scy** CAPI3REF: Changeset Iterator Handle 10036342292Scy** 10037342292Scy** An instance of this object acts as a cursor for iterating 10038342292Scy** over the elements of a [changeset] or [patchset]. 10039305002Scy*/ 10040305002Scytypedef struct sqlite3_changeset_iter sqlite3_changeset_iter; 10041305002Scy 10042305002Scy/* 10043305002Scy** CAPI3REF: Create A New Session Object 10044342292Scy** CONSTRUCTOR: sqlite3_session 10045305002Scy** 10046305002Scy** Create a new session object attached to database handle db. If successful, 10047305002Scy** a pointer to the new object is written to *ppSession and SQLITE_OK is 10048305002Scy** returned. If an error occurs, *ppSession is set to NULL and an SQLite 10049305002Scy** error code (e.g. SQLITE_NOMEM) is returned. 10050305002Scy** 10051305002Scy** It is possible to create multiple session objects attached to a single 10052305002Scy** database handle. 10053305002Scy** 10054305002Scy** Session objects created using this function should be deleted using the 10055305002Scy** [sqlite3session_delete()] function before the database handle that they 10056305002Scy** are attached to is itself closed. If the database handle is closed before 10057305002Scy** the session object is deleted, then the results of calling any session 10058305002Scy** module function, including [sqlite3session_delete()] on the session object 10059305002Scy** are undefined. 10060305002Scy** 10061305002Scy** Because the session module uses the [sqlite3_preupdate_hook()] API, it 10062305002Scy** is not possible for an application to register a pre-update hook on a 10063305002Scy** database handle that has one or more session objects attached. Nor is 10064305002Scy** it possible to create a session object attached to a database handle for 10065366076Scy** which a pre-update hook is already defined. The results of attempting 10066305002Scy** either of these things are undefined. 10067305002Scy** 10068305002Scy** The session object will be used to create changesets for tables in 10069305002Scy** database zDb, where zDb is either "main", or "temp", or the name of an 10070305002Scy** attached database. It is not an error if database zDb is not attached 10071305002Scy** to the database when the session object is created. 10072305002Scy*/ 10073322444SpeterSQLITE_API int sqlite3session_create( 10074305002Scy sqlite3 *db, /* Database handle */ 10075305002Scy const char *zDb, /* Name of db (e.g. "main") */ 10076305002Scy sqlite3_session **ppSession /* OUT: New session object */ 10077305002Scy); 10078305002Scy 10079305002Scy/* 10080305002Scy** CAPI3REF: Delete A Session Object 10081342292Scy** DESTRUCTOR: sqlite3_session 10082305002Scy** 10083366076Scy** Delete a session object previously allocated using 10084305002Scy** [sqlite3session_create()]. Once a session object has been deleted, the 10085305002Scy** results of attempting to use pSession with any other session module 10086305002Scy** function are undefined. 10087305002Scy** 10088305002Scy** Session objects must be deleted before the database handle to which they 10089366076Scy** are attached is closed. Refer to the documentation for 10090305002Scy** [sqlite3session_create()] for details. 10091305002Scy*/ 10092322444SpeterSQLITE_API void sqlite3session_delete(sqlite3_session *pSession); 10093305002Scy 10094305002Scy 10095305002Scy/* 10096305002Scy** CAPI3REF: Enable Or Disable A Session Object 10097342292Scy** METHOD: sqlite3_session 10098305002Scy** 10099305002Scy** Enable or disable the recording of changes by a session object. When 10100305002Scy** enabled, a session object records changes made to the database. When 10101305002Scy** disabled - it does not. A newly created session object is enabled. 10102305002Scy** Refer to the documentation for [sqlite3session_changeset()] for further 10103305002Scy** details regarding how enabling and disabling a session object affects 10104305002Scy** the eventual changesets. 10105305002Scy** 10106305002Scy** Passing zero to this function disables the session. Passing a value 10107366076Scy** greater than zero enables it. Passing a value less than zero is a 10108305002Scy** no-op, and may be used to query the current state of the session. 10109305002Scy** 10110366076Scy** The return value indicates the final state of the session object: 0 if 10111305002Scy** the session is disabled, or 1 if it is enabled. 10112305002Scy*/ 10113322444SpeterSQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable); 10114305002Scy 10115305002Scy/* 10116305002Scy** CAPI3REF: Set Or Clear the Indirect Change Flag 10117342292Scy** METHOD: sqlite3_session 10118305002Scy** 10119305002Scy** Each change recorded by a session object is marked as either direct or 10120305002Scy** indirect. A change is marked as indirect if either: 10121305002Scy** 10122305002Scy** <ul> 10123305002Scy** <li> The session object "indirect" flag is set when the change is 10124305002Scy** made, or 10125366076Scy** <li> The change is made by an SQL trigger or foreign key action 10126305002Scy** instead of directly as a result of a users SQL statement. 10127305002Scy** </ul> 10128305002Scy** 10129305002Scy** If a single row is affected by more than one operation within a session, 10130305002Scy** then the change is considered indirect if all operations meet the criteria 10131305002Scy** for an indirect change above, or direct otherwise. 10132305002Scy** 10133305002Scy** This function is used to set, clear or query the session object indirect 10134305002Scy** flag. If the second argument passed to this function is zero, then the 10135305002Scy** indirect flag is cleared. If it is greater than zero, the indirect flag 10136305002Scy** is set. Passing a value less than zero does not modify the current value 10137366076Scy** of the indirect flag, and may be used to query the current state of the 10138305002Scy** indirect flag for the specified session object. 10139305002Scy** 10140366076Scy** The return value indicates the final state of the indirect flag: 0 if 10141305002Scy** it is clear, or 1 if it is set. 10142305002Scy*/ 10143322444SpeterSQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect); 10144305002Scy 10145305002Scy/* 10146305002Scy** CAPI3REF: Attach A Table To A Session Object 10147342292Scy** METHOD: sqlite3_session 10148305002Scy** 10149305002Scy** If argument zTab is not NULL, then it is the name of a table to attach 10150366076Scy** to the session object passed as the first argument. All subsequent changes 10151366076Scy** made to the table while the session object is enabled will be recorded. See 10152305002Scy** documentation for [sqlite3session_changeset()] for further details. 10153305002Scy** 10154305002Scy** Or, if argument zTab is NULL, then changes are recorded for all tables 10155366076Scy** in the database. If additional tables are added to the database (by 10156366076Scy** executing "CREATE TABLE" statements) after this call is made, changes for 10157305002Scy** the new tables are also recorded. 10158305002Scy** 10159305002Scy** Changes can only be recorded for tables that have a PRIMARY KEY explicitly 10160366076Scy** defined as part of their CREATE TABLE statement. It does not matter if the 10161305002Scy** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY 10162305002Scy** KEY may consist of a single column, or may be a composite key. 10163366076Scy** 10164305002Scy** It is not an error if the named table does not exist in the database. Nor 10165305002Scy** is it an error if the named table does not have a PRIMARY KEY. However, 10166305002Scy** no changes will be recorded in either of these scenarios. 10167305002Scy** 10168305002Scy** Changes are not recorded for individual rows that have NULL values stored 10169305002Scy** in one or more of their PRIMARY KEY columns. 10170305002Scy** 10171366076Scy** SQLITE_OK is returned if the call completes without error. Or, if an error 10172305002Scy** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned. 10173342292Scy** 10174342292Scy** <h3>Special sqlite_stat1 Handling</h3> 10175342292Scy** 10176366076Scy** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to 10177342292Scy** some of the rules above. In SQLite, the schema of sqlite_stat1 is: 10178342292Scy** <pre> 10179366076Scy** CREATE TABLE sqlite_stat1(tbl,idx,stat) 10180342292Scy** </pre> 10181342292Scy** 10182366076Scy** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are 10183366076Scy** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes 10184342292Scy** are recorded for rows for which (idx IS NULL) is true. However, for such 10185342292Scy** rows a zero-length blob (SQL value X'') is stored in the changeset or 10186342292Scy** patchset instead of a NULL value. This allows such changesets to be 10187342292Scy** manipulated by legacy implementations of sqlite3changeset_invert(), 10188342292Scy** concat() and similar. 10189342292Scy** 10190366076Scy** The sqlite3changeset_apply() function automatically converts the 10191342292Scy** zero-length blob back to a NULL value when updating the sqlite_stat1 10192342292Scy** table. However, if the application calls sqlite3changeset_new(), 10193366076Scy** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset 10194342292Scy** iterator directly (including on a changeset iterator passed to a 10195342292Scy** conflict-handler callback) then the X'' value is returned. The application 10196342292Scy** must translate X'' to NULL itself if required. 10197342292Scy** 10198342292Scy** Legacy (older than 3.22.0) versions of the sessions module cannot capture 10199342292Scy** changes made to the sqlite_stat1 table. Legacy versions of the 10200342292Scy** sqlite3changeset_apply() function silently ignore any modifications to the 10201342292Scy** sqlite_stat1 table that are part of a changeset or patchset. 10202305002Scy*/ 10203322444SpeterSQLITE_API int sqlite3session_attach( 10204305002Scy sqlite3_session *pSession, /* Session object */ 10205305002Scy const char *zTab /* Table name */ 10206305002Scy); 10207305002Scy 10208305002Scy/* 10209305002Scy** CAPI3REF: Set a table filter on a Session Object. 10210342292Scy** METHOD: sqlite3_session 10211305002Scy** 10212366076Scy** The second argument (xFilter) is the "filter callback". For changes to rows 10213322444Speter** in tables that are not attached to the Session object, the filter is called 10214366076Scy** to determine whether changes to the table's rows should be tracked or not. 10215366076Scy** If xFilter returns 0, changes are not tracked. Note that once a table is 10216305002Scy** attached, xFilter will not be called again. 10217305002Scy*/ 10218322444SpeterSQLITE_API void sqlite3session_table_filter( 10219305002Scy sqlite3_session *pSession, /* Session object */ 10220305002Scy int(*xFilter)( 10221305002Scy void *pCtx, /* Copy of third arg to _filter_table() */ 10222305002Scy const char *zTab /* Table name */ 10223305002Scy ), 10224305002Scy void *pCtx /* First argument passed to xFilter */ 10225305002Scy); 10226305002Scy 10227305002Scy/* 10228305002Scy** CAPI3REF: Generate A Changeset From A Session Object 10229342292Scy** METHOD: sqlite3_session 10230305002Scy** 10231366076Scy** Obtain a changeset containing changes to the tables attached to the 10232366076Scy** session object passed as the first argument. If successful, 10233366076Scy** set *ppChangeset to point to a buffer containing the changeset 10234305002Scy** and *pnChangeset to the size of the changeset in bytes before returning 10235305002Scy** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to 10236305002Scy** zero and return an SQLite error code. 10237305002Scy** 10238305002Scy** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes, 10239305002Scy** each representing a change to a single row of an attached table. An INSERT 10240305002Scy** change contains the values of each field of a new database row. A DELETE 10241305002Scy** contains the original values of each field of a deleted database row. An 10242305002Scy** UPDATE change contains the original values of each field of an updated 10243305002Scy** database row along with the updated values for each updated non-primary-key 10244305002Scy** column. It is not possible for an UPDATE change to represent a change that 10245305002Scy** modifies the values of primary key columns. If such a change is made, it 10246305002Scy** is represented in a changeset as a DELETE followed by an INSERT. 10247305002Scy** 10248366076Scy** Changes are not recorded for rows that have NULL values stored in one or 10249305002Scy** more of their PRIMARY KEY columns. If such a row is inserted or deleted, 10250305002Scy** no corresponding change is present in the changesets returned by this 10251305002Scy** function. If an existing row with one or more NULL values stored in 10252305002Scy** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL, 10253305002Scy** only an INSERT is appears in the changeset. Similarly, if an existing row 10254305002Scy** with non-NULL PRIMARY KEY values is updated so that one or more of its 10255305002Scy** PRIMARY KEY columns are set to NULL, the resulting changeset contains a 10256305002Scy** DELETE change only. 10257305002Scy** 10258305002Scy** The contents of a changeset may be traversed using an iterator created 10259305002Scy** using the [sqlite3changeset_start()] API. A changeset may be applied to 10260305002Scy** a database with a compatible schema using the [sqlite3changeset_apply()] 10261305002Scy** API. 10262305002Scy** 10263305002Scy** Within a changeset generated by this function, all changes related to a 10264305002Scy** single table are grouped together. In other words, when iterating through 10265305002Scy** a changeset or when applying a changeset to a database, all changes related 10266305002Scy** to a single table are processed before moving on to the next table. Tables 10267305002Scy** are sorted in the same order in which they were attached (or auto-attached) 10268305002Scy** to the sqlite3_session object. The order in which the changes related to 10269305002Scy** a single table are stored is undefined. 10270305002Scy** 10271305002Scy** Following a successful call to this function, it is the responsibility of 10272305002Scy** the caller to eventually free the buffer that *ppChangeset points to using 10273305002Scy** [sqlite3_free()]. 10274305002Scy** 10275305002Scy** <h3>Changeset Generation</h3> 10276305002Scy** 10277305002Scy** Once a table has been attached to a session object, the session object 10278305002Scy** records the primary key values of all new rows inserted into the table. 10279305002Scy** It also records the original primary key and other column values of any 10280305002Scy** deleted or updated rows. For each unique primary key value, data is only 10281305002Scy** recorded once - the first time a row with said primary key is inserted, 10282305002Scy** updated or deleted in the lifetime of the session. 10283305002Scy** 10284305002Scy** There is one exception to the previous paragraph: when a row is inserted, 10285305002Scy** updated or deleted, if one or more of its primary key columns contain a 10286305002Scy** NULL value, no record of the change is made. 10287305002Scy** 10288305002Scy** The session object therefore accumulates two types of records - those 10289305002Scy** that consist of primary key values only (created when the user inserts 10290305002Scy** a new record) and those that consist of the primary key values and the 10291305002Scy** original values of other table columns (created when the users deletes 10292305002Scy** or updates a record). 10293305002Scy** 10294305002Scy** When this function is called, the requested changeset is created using 10295305002Scy** both the accumulated records and the current contents of the database 10296305002Scy** file. Specifically: 10297305002Scy** 10298305002Scy** <ul> 10299305002Scy** <li> For each record generated by an insert, the database is queried 10300305002Scy** for a row with a matching primary key. If one is found, an INSERT 10301366076Scy** change is added to the changeset. If no such row is found, no change 10302305002Scy** is added to the changeset. 10303305002Scy** 10304366076Scy** <li> For each record generated by an update or delete, the database is 10305305002Scy** queried for a row with a matching primary key. If such a row is 10306305002Scy** found and one or more of the non-primary key fields have been 10307366076Scy** modified from their original values, an UPDATE change is added to 10308366076Scy** the changeset. Or, if no such row is found in the table, a DELETE 10309305002Scy** change is added to the changeset. If there is a row with a matching 10310305002Scy** primary key in the database, but all fields contain their original 10311305002Scy** values, no change is added to the changeset. 10312305002Scy** </ul> 10313305002Scy** 10314305002Scy** This means, amongst other things, that if a row is inserted and then later 10315305002Scy** deleted while a session object is active, neither the insert nor the delete 10316366076Scy** will be present in the changeset. Or if a row is deleted and then later a 10317305002Scy** row with the same primary key values inserted while a session object is 10318305002Scy** active, the resulting changeset will contain an UPDATE change instead of 10319305002Scy** a DELETE and an INSERT. 10320305002Scy** 10321305002Scy** When a session object is disabled (see the [sqlite3session_enable()] API), 10322305002Scy** it does not accumulate records when rows are inserted, updated or deleted. 10323305002Scy** This may appear to have some counter-intuitive effects if a single row 10324305002Scy** is written to more than once during a session. For example, if a row 10325366076Scy** is inserted while a session object is enabled, then later deleted while 10326305002Scy** the same session object is disabled, no INSERT record will appear in the 10327305002Scy** changeset, even though the delete took place while the session was disabled. 10328366076Scy** Or, if one field of a row is updated while a session is disabled, and 10329305002Scy** another field of the same row is updated while the session is enabled, the 10330305002Scy** resulting changeset will contain an UPDATE change that updates both fields. 10331305002Scy*/ 10332322444SpeterSQLITE_API int sqlite3session_changeset( 10333305002Scy sqlite3_session *pSession, /* Session object */ 10334305002Scy int *pnChangeset, /* OUT: Size of buffer at *ppChangeset */ 10335305002Scy void **ppChangeset /* OUT: Buffer containing changeset */ 10336305002Scy); 10337305002Scy 10338305002Scy/* 10339342292Scy** CAPI3REF: Load The Difference Between Tables Into A Session 10340342292Scy** METHOD: sqlite3_session 10341305002Scy** 10342305002Scy** If it is not already attached to the session object passed as the first 10343305002Scy** argument, this function attaches table zTbl in the same manner as the 10344305002Scy** [sqlite3session_attach()] function. If zTbl does not exist, or if it 10345305002Scy** does not have a primary key, this function is a no-op (but does not return 10346305002Scy** an error). 10347305002Scy** 10348305002Scy** Argument zFromDb must be the name of a database ("main", "temp" etc.) 10349366076Scy** attached to the same database handle as the session object that contains 10350305002Scy** a table compatible with the table attached to the session by this function. 10351305002Scy** A table is considered compatible if it: 10352305002Scy** 10353305002Scy** <ul> 10354305002Scy** <li> Has the same name, 10355305002Scy** <li> Has the same set of columns declared in the same order, and 10356305002Scy** <li> Has the same PRIMARY KEY definition. 10357305002Scy** </ul> 10358305002Scy** 10359305002Scy** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables 10360305002Scy** are compatible but do not have any PRIMARY KEY columns, it is not an error 10361305002Scy** but no changes are added to the session object. As with other session 10362305002Scy** APIs, tables without PRIMARY KEYs are simply ignored. 10363305002Scy** 10364305002Scy** This function adds a set of changes to the session object that could be 10365366076Scy** used to update the table in database zFrom (call this the "from-table") 10366366076Scy** so that its content is the same as the table attached to the session 10367305002Scy** object (call this the "to-table"). Specifically: 10368305002Scy** 10369305002Scy** <ul> 10370366076Scy** <li> For each row (primary key) that exists in the to-table but not in 10371305002Scy** the from-table, an INSERT record is added to the session object. 10372305002Scy** 10373366076Scy** <li> For each row (primary key) that exists in the to-table but not in 10374305002Scy** the from-table, a DELETE record is added to the session object. 10375305002Scy** 10376366076Scy** <li> For each row (primary key) that exists in both tables, but features 10377322444Speter** different non-PK values in each, an UPDATE record is added to the 10378366076Scy** session. 10379305002Scy** </ul> 10380305002Scy** 10381305002Scy** To clarify, if this function is called and then a changeset constructed 10382366076Scy** using [sqlite3session_changeset()], then after applying that changeset to 10383366076Scy** database zFrom the contents of the two compatible tables would be 10384305002Scy** identical. 10385305002Scy** 10386305002Scy** It an error if database zFrom does not exist or does not contain the 10387305002Scy** required compatible table. 10388305002Scy** 10389361456Scy** If the operation is successful, SQLITE_OK is returned. Otherwise, an SQLite 10390305002Scy** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg 10391366076Scy** may be set to point to a buffer containing an English language error 10392305002Scy** message. It is the responsibility of the caller to free this buffer using 10393305002Scy** sqlite3_free(). 10394305002Scy*/ 10395322444SpeterSQLITE_API int sqlite3session_diff( 10396305002Scy sqlite3_session *pSession, 10397305002Scy const char *zFromDb, 10398305002Scy const char *zTbl, 10399305002Scy char **pzErrMsg 10400305002Scy); 10401305002Scy 10402305002Scy 10403305002Scy/* 10404305002Scy** CAPI3REF: Generate A Patchset From A Session Object 10405342292Scy** METHOD: sqlite3_session 10406305002Scy** 10407305002Scy** The differences between a patchset and a changeset are that: 10408305002Scy** 10409305002Scy** <ul> 10410366076Scy** <li> DELETE records consist of the primary key fields only. The 10411305002Scy** original values of other fields are omitted. 10412366076Scy** <li> The original values of any modified fields are omitted from 10413305002Scy** UPDATE records. 10414305002Scy** </ul> 10415305002Scy** 10416366076Scy** A patchset blob may be used with up to date versions of all 10417366076Scy** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(), 10418305002Scy** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly, 10419305002Scy** attempting to use a patchset blob with old versions of the 10420366076Scy** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error. 10421305002Scy** 10422366076Scy** Because the non-primary key "old.*" fields are omitted, no 10423305002Scy** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset 10424305002Scy** is passed to the sqlite3changeset_apply() API. Other conflict types work 10425305002Scy** in the same way as for changesets. 10426305002Scy** 10427305002Scy** Changes within a patchset are ordered in the same way as for changesets 10428305002Scy** generated by the sqlite3session_changeset() function (i.e. all changes for 10429305002Scy** a single table are grouped together, tables appear in the order in which 10430305002Scy** they were attached to the session object). 10431305002Scy*/ 10432322444SpeterSQLITE_API int sqlite3session_patchset( 10433305002Scy sqlite3_session *pSession, /* Session object */ 10434342292Scy int *pnPatchset, /* OUT: Size of buffer at *ppPatchset */ 10435342292Scy void **ppPatchset /* OUT: Buffer containing patchset */ 10436305002Scy); 10437305002Scy 10438305002Scy/* 10439305002Scy** CAPI3REF: Test if a changeset has recorded any changes. 10440305002Scy** 10441366076Scy** Return non-zero if no changes to attached tables have been recorded by 10442366076Scy** the session object passed as the first argument. Otherwise, if one or 10443305002Scy** more changes have been recorded, return zero. 10444305002Scy** 10445305002Scy** Even if this function returns zero, it is possible that calling 10446305002Scy** [sqlite3session_changeset()] on the session handle may still return a 10447366076Scy** changeset that contains no changes. This can happen when a row in 10448366076Scy** an attached table is modified and then later on the original values 10449305002Scy** are restored. However, if this function returns non-zero, then it is 10450366076Scy** guaranteed that a call to sqlite3session_changeset() will return a 10451305002Scy** changeset containing zero changes. 10452305002Scy*/ 10453322444SpeterSQLITE_API int sqlite3session_isempty(sqlite3_session *pSession); 10454305002Scy 10455305002Scy/* 10456369951Scy** CAPI3REF: Query for the amount of heap memory used by a session object. 10457369951Scy** 10458369951Scy** This API returns the total amount of heap memory in bytes currently 10459369951Scy** used by the session object passed as the only argument. 10460369951Scy*/ 10461369951ScySQLITE_API sqlite3_int64 sqlite3session_memory_used(sqlite3_session *pSession); 10462369951Scy 10463369951Scy/* 10464366076Scy** CAPI3REF: Create An Iterator To Traverse A Changeset 10465342292Scy** CONSTRUCTOR: sqlite3_changeset_iter 10466305002Scy** 10467305002Scy** Create an iterator used to iterate through the contents of a changeset. 10468305002Scy** If successful, *pp is set to point to the iterator handle and SQLITE_OK 10469305002Scy** is returned. Otherwise, if an error occurs, *pp is set to zero and an 10470305002Scy** SQLite error code is returned. 10471305002Scy** 10472366076Scy** The following functions can be used to advance and query a changeset 10473305002Scy** iterator created by this function: 10474305002Scy** 10475305002Scy** <ul> 10476305002Scy** <li> [sqlite3changeset_next()] 10477305002Scy** <li> [sqlite3changeset_op()] 10478305002Scy** <li> [sqlite3changeset_new()] 10479305002Scy** <li> [sqlite3changeset_old()] 10480305002Scy** </ul> 10481305002Scy** 10482305002Scy** It is the responsibility of the caller to eventually destroy the iterator 10483305002Scy** by passing it to [sqlite3changeset_finalize()]. The buffer containing the 10484305002Scy** changeset (pChangeset) must remain valid until after the iterator is 10485305002Scy** destroyed. 10486305002Scy** 10487305002Scy** Assuming the changeset blob was created by one of the 10488305002Scy** [sqlite3session_changeset()], [sqlite3changeset_concat()] or 10489366076Scy** [sqlite3changeset_invert()] functions, all changes within the changeset 10490366076Scy** that apply to a single table are grouped together. This means that when 10491366076Scy** an application iterates through a changeset using an iterator created by 10492366076Scy** this function, all changes that relate to a single table are visited 10493366076Scy** consecutively. There is no chance that the iterator will visit a change 10494366076Scy** the applies to table X, then one for table Y, and then later on visit 10495305002Scy** another change for table X. 10496342292Scy** 10497342292Scy** The behavior of sqlite3changeset_start_v2() and its streaming equivalent 10498342292Scy** may be modified by passing a combination of 10499342292Scy** [SQLITE_CHANGESETSTART_INVERT | supported flags] as the 4th parameter. 10500342292Scy** 10501342292Scy** Note that the sqlite3changeset_start_v2() API is still <b>experimental</b> 10502342292Scy** and therefore subject to change. 10503305002Scy*/ 10504322444SpeterSQLITE_API int sqlite3changeset_start( 10505305002Scy sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ 10506305002Scy int nChangeset, /* Size of changeset blob in bytes */ 10507305002Scy void *pChangeset /* Pointer to blob containing changeset */ 10508305002Scy); 10509342292ScySQLITE_API int sqlite3changeset_start_v2( 10510342292Scy sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ 10511342292Scy int nChangeset, /* Size of changeset blob in bytes */ 10512342292Scy void *pChangeset, /* Pointer to blob containing changeset */ 10513342292Scy int flags /* SESSION_CHANGESETSTART_* flags */ 10514342292Scy); 10515305002Scy 10516342292Scy/* 10517342292Scy** CAPI3REF: Flags for sqlite3changeset_start_v2 10518342292Scy** 10519342292Scy** The following flags may passed via the 4th parameter to 10520342292Scy** [sqlite3changeset_start_v2] and [sqlite3changeset_start_v2_strm]: 10521342292Scy** 10522342292Scy** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd> 10523342292Scy** Invert the changeset while iterating through it. This is equivalent to 10524342292Scy** inverting a changeset using sqlite3changeset_invert() before applying it. 10525342292Scy** It is an error to specify this flag with a patchset. 10526342292Scy*/ 10527342292Scy#define SQLITE_CHANGESETSTART_INVERT 0x0002 10528305002Scy 10529342292Scy 10530305002Scy/* 10531305002Scy** CAPI3REF: Advance A Changeset Iterator 10532342292Scy** METHOD: sqlite3_changeset_iter 10533305002Scy** 10534361456Scy** This function may only be used with iterators created by the function 10535305002Scy** [sqlite3changeset_start()]. If it is called on an iterator passed to 10536305002Scy** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE 10537305002Scy** is returned and the call has no effect. 10538305002Scy** 10539305002Scy** Immediately after an iterator is created by sqlite3changeset_start(), it 10540305002Scy** does not point to any change in the changeset. Assuming the changeset 10541305002Scy** is not empty, the first call to this function advances the iterator to 10542305002Scy** point to the first change in the changeset. Each subsequent call advances 10543305002Scy** the iterator to point to the next change in the changeset (if any). If 10544305002Scy** no error occurs and the iterator points to a valid change after a call 10545366076Scy** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned. 10546305002Scy** Otherwise, if all changes in the changeset have already been visited, 10547305002Scy** SQLITE_DONE is returned. 10548305002Scy** 10549366076Scy** If an error occurs, an SQLite error code is returned. Possible error 10550366076Scy** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or 10551305002Scy** SQLITE_NOMEM. 10552305002Scy*/ 10553322444SpeterSQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter); 10554305002Scy 10555305002Scy/* 10556305002Scy** CAPI3REF: Obtain The Current Operation From A Changeset Iterator 10557342292Scy** METHOD: sqlite3_changeset_iter 10558305002Scy** 10559305002Scy** The pIter argument passed to this function may either be an iterator 10560305002Scy** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator 10561305002Scy** created by [sqlite3changeset_start()]. In the latter case, the most recent 10562305002Scy** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this 10563305002Scy** is not the case, this function returns [SQLITE_MISUSE]. 10564305002Scy** 10565369951Scy** Arguments pOp, pnCol and pzTab may not be NULL. Upon return, three 10566369951Scy** outputs are set through these pointers: 10567369951Scy** 10568369951Scy** *pOp is set to one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], 10569369951Scy** depending on the type of change that the iterator currently points to; 10570369951Scy** 10571369951Scy** *pnCol is set to the number of columns in the table affected by the change; and 10572369951Scy** 10573369951Scy** *pzTab is set to point to a nul-terminated utf-8 encoded string containing 10574369951Scy** the name of the table affected by the current change. The buffer remains 10575369951Scy** valid until either sqlite3changeset_next() is called on the iterator 10576369951Scy** or until the conflict-handler function returns. 10577369951Scy** 10578369951Scy** If pbIndirect is not NULL, then *pbIndirect is set to true (1) if the change 10579305002Scy** is an indirect change, or false (0) otherwise. See the documentation for 10580305002Scy** [sqlite3session_indirect()] for a description of direct and indirect 10581369951Scy** changes. 10582305002Scy** 10583305002Scy** If no error occurs, SQLITE_OK is returned. If an error does occur, an 10584305002Scy** SQLite error code is returned. The values of the output variables may not 10585305002Scy** be trusted in this case. 10586305002Scy*/ 10587322444SpeterSQLITE_API int sqlite3changeset_op( 10588305002Scy sqlite3_changeset_iter *pIter, /* Iterator object */ 10589305002Scy const char **pzTab, /* OUT: Pointer to table name */ 10590305002Scy int *pnCol, /* OUT: Number of columns in table */ 10591305002Scy int *pOp, /* OUT: SQLITE_INSERT, DELETE or UPDATE */ 10592305002Scy int *pbIndirect /* OUT: True for an 'indirect' change */ 10593305002Scy); 10594305002Scy 10595305002Scy/* 10596305002Scy** CAPI3REF: Obtain The Primary Key Definition Of A Table 10597342292Scy** METHOD: sqlite3_changeset_iter 10598305002Scy** 10599305002Scy** For each modified table, a changeset includes the following: 10600305002Scy** 10601305002Scy** <ul> 10602305002Scy** <li> The number of columns in the table, and 10603305002Scy** <li> Which of those columns make up the tables PRIMARY KEY. 10604305002Scy** </ul> 10605305002Scy** 10606305002Scy** This function is used to find which columns comprise the PRIMARY KEY of 10607305002Scy** the table modified by the change that iterator pIter currently points to. 10608305002Scy** If successful, *pabPK is set to point to an array of nCol entries, where 10609305002Scy** nCol is the number of columns in the table. Elements of *pabPK are set to 10610305002Scy** 0x01 if the corresponding column is part of the tables primary key, or 10611305002Scy** 0x00 if it is not. 10612305002Scy** 10613322444Speter** If argument pnCol is not NULL, then *pnCol is set to the number of columns 10614305002Scy** in the table. 10615305002Scy** 10616305002Scy** If this function is called when the iterator does not point to a valid 10617305002Scy** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise, 10618305002Scy** SQLITE_OK is returned and the output variables populated as described 10619305002Scy** above. 10620305002Scy*/ 10621322444SpeterSQLITE_API int sqlite3changeset_pk( 10622305002Scy sqlite3_changeset_iter *pIter, /* Iterator object */ 10623305002Scy unsigned char **pabPK, /* OUT: Array of boolean - true for PK cols */ 10624305002Scy int *pnCol /* OUT: Number of entries in output array */ 10625305002Scy); 10626305002Scy 10627305002Scy/* 10628305002Scy** CAPI3REF: Obtain old.* Values From A Changeset Iterator 10629342292Scy** METHOD: sqlite3_changeset_iter 10630305002Scy** 10631305002Scy** The pIter argument passed to this function may either be an iterator 10632305002Scy** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator 10633305002Scy** created by [sqlite3changeset_start()]. In the latter case, the most recent 10634366076Scy** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. 10635305002Scy** Furthermore, it may only be called if the type of change that the iterator 10636305002Scy** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise, 10637305002Scy** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. 10638305002Scy** 10639305002Scy** Argument iVal must be greater than or equal to 0, and less than the number 10640305002Scy** of columns in the table affected by the current change. Otherwise, 10641305002Scy** [SQLITE_RANGE] is returned and *ppValue is set to NULL. 10642305002Scy** 10643305002Scy** If successful, this function sets *ppValue to point to a protected 10644366076Scy** sqlite3_value object containing the iVal'th value from the vector of 10645305002Scy** original row values stored as part of the UPDATE or DELETE change and 10646366076Scy** returns SQLITE_OK. The name of the function comes from the fact that this 10647305002Scy** is similar to the "old.*" columns available to update or delete triggers. 10648305002Scy** 10649305002Scy** If some other error occurs (e.g. an OOM condition), an SQLite error code 10650305002Scy** is returned and *ppValue is set to NULL. 10651305002Scy*/ 10652322444SpeterSQLITE_API int sqlite3changeset_old( 10653305002Scy sqlite3_changeset_iter *pIter, /* Changeset iterator */ 10654305002Scy int iVal, /* Column number */ 10655305002Scy sqlite3_value **ppValue /* OUT: Old value (or NULL pointer) */ 10656305002Scy); 10657305002Scy 10658305002Scy/* 10659305002Scy** CAPI3REF: Obtain new.* Values From A Changeset Iterator 10660342292Scy** METHOD: sqlite3_changeset_iter 10661305002Scy** 10662305002Scy** The pIter argument passed to this function may either be an iterator 10663305002Scy** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator 10664305002Scy** created by [sqlite3changeset_start()]. In the latter case, the most recent 10665366076Scy** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. 10666305002Scy** Furthermore, it may only be called if the type of change that the iterator 10667305002Scy** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise, 10668305002Scy** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. 10669305002Scy** 10670305002Scy** Argument iVal must be greater than or equal to 0, and less than the number 10671305002Scy** of columns in the table affected by the current change. Otherwise, 10672305002Scy** [SQLITE_RANGE] is returned and *ppValue is set to NULL. 10673305002Scy** 10674305002Scy** If successful, this function sets *ppValue to point to a protected 10675366076Scy** sqlite3_value object containing the iVal'th value from the vector of 10676305002Scy** new row values stored as part of the UPDATE or INSERT change and 10677305002Scy** returns SQLITE_OK. If the change is an UPDATE and does not include 10678366076Scy** a new value for the requested column, *ppValue is set to NULL and 10679366076Scy** SQLITE_OK returned. The name of the function comes from the fact that 10680366076Scy** this is similar to the "new.*" columns available to update or delete 10681305002Scy** triggers. 10682305002Scy** 10683305002Scy** If some other error occurs (e.g. an OOM condition), an SQLite error code 10684305002Scy** is returned and *ppValue is set to NULL. 10685305002Scy*/ 10686322444SpeterSQLITE_API int sqlite3changeset_new( 10687305002Scy sqlite3_changeset_iter *pIter, /* Changeset iterator */ 10688305002Scy int iVal, /* Column number */ 10689305002Scy sqlite3_value **ppValue /* OUT: New value (or NULL pointer) */ 10690305002Scy); 10691305002Scy 10692305002Scy/* 10693305002Scy** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator 10694342292Scy** METHOD: sqlite3_changeset_iter 10695305002Scy** 10696305002Scy** This function should only be used with iterator objects passed to a 10697305002Scy** conflict-handler callback by [sqlite3changeset_apply()] with either 10698305002Scy** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function 10699305002Scy** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue 10700305002Scy** is set to NULL. 10701305002Scy** 10702305002Scy** Argument iVal must be greater than or equal to 0, and less than the number 10703305002Scy** of columns in the table affected by the current change. Otherwise, 10704305002Scy** [SQLITE_RANGE] is returned and *ppValue is set to NULL. 10705305002Scy** 10706305002Scy** If successful, this function sets *ppValue to point to a protected 10707366076Scy** sqlite3_value object containing the iVal'th value from the 10708305002Scy** "conflicting row" associated with the current conflict-handler callback 10709305002Scy** and returns SQLITE_OK. 10710305002Scy** 10711305002Scy** If some other error occurs (e.g. an OOM condition), an SQLite error code 10712305002Scy** is returned and *ppValue is set to NULL. 10713305002Scy*/ 10714322444SpeterSQLITE_API int sqlite3changeset_conflict( 10715305002Scy sqlite3_changeset_iter *pIter, /* Changeset iterator */ 10716305002Scy int iVal, /* Column number */ 10717305002Scy sqlite3_value **ppValue /* OUT: Value from conflicting row */ 10718305002Scy); 10719305002Scy 10720305002Scy/* 10721305002Scy** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations 10722342292Scy** METHOD: sqlite3_changeset_iter 10723305002Scy** 10724305002Scy** This function may only be called with an iterator passed to an 10725305002Scy** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case 10726305002Scy** it sets the output variable to the total number of known foreign key 10727305002Scy** violations in the destination database and returns SQLITE_OK. 10728305002Scy** 10729305002Scy** In all other cases this function returns SQLITE_MISUSE. 10730305002Scy*/ 10731322444SpeterSQLITE_API int sqlite3changeset_fk_conflicts( 10732305002Scy sqlite3_changeset_iter *pIter, /* Changeset iterator */ 10733305002Scy int *pnOut /* OUT: Number of FK violations */ 10734305002Scy); 10735305002Scy 10736305002Scy 10737305002Scy/* 10738305002Scy** CAPI3REF: Finalize A Changeset Iterator 10739342292Scy** METHOD: sqlite3_changeset_iter 10740305002Scy** 10741305002Scy** This function is used to finalize an iterator allocated with 10742305002Scy** [sqlite3changeset_start()]. 10743305002Scy** 10744305002Scy** This function should only be called on iterators created using the 10745305002Scy** [sqlite3changeset_start()] function. If an application calls this 10746305002Scy** function with an iterator passed to a conflict-handler by 10747305002Scy** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the 10748305002Scy** call has no effect. 10749305002Scy** 10750305002Scy** If an error was encountered within a call to an sqlite3changeset_xxx() 10751366076Scy** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an 10752305002Scy** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding 10753305002Scy** to that error is returned by this function. Otherwise, SQLITE_OK is 10754305002Scy** returned. This is to allow the following pattern (pseudo-code): 10755305002Scy** 10756342292Scy** <pre> 10757305002Scy** sqlite3changeset_start(); 10758305002Scy** while( SQLITE_ROW==sqlite3changeset_next() ){ 10759305002Scy** // Do something with change. 10760305002Scy** } 10761305002Scy** rc = sqlite3changeset_finalize(); 10762305002Scy** if( rc!=SQLITE_OK ){ 10763366076Scy** // An error has occurred 10764305002Scy** } 10765342292Scy** </pre> 10766305002Scy*/ 10767322444SpeterSQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter); 10768305002Scy 10769305002Scy/* 10770305002Scy** CAPI3REF: Invert A Changeset 10771305002Scy** 10772305002Scy** This function is used to "invert" a changeset object. Applying an inverted 10773305002Scy** changeset to a database reverses the effects of applying the uninverted 10774305002Scy** changeset. Specifically: 10775305002Scy** 10776305002Scy** <ul> 10777305002Scy** <li> Each DELETE change is changed to an INSERT, and 10778305002Scy** <li> Each INSERT change is changed to a DELETE, and 10779305002Scy** <li> For each UPDATE change, the old.* and new.* values are exchanged. 10780305002Scy** </ul> 10781305002Scy** 10782305002Scy** This function does not change the order in which changes appear within 10783305002Scy** the changeset. It merely reverses the sense of each individual change. 10784305002Scy** 10785305002Scy** If successful, a pointer to a buffer containing the inverted changeset 10786305002Scy** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and 10787305002Scy** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are 10788305002Scy** zeroed and an SQLite error code returned. 10789305002Scy** 10790305002Scy** It is the responsibility of the caller to eventually call sqlite3_free() 10791366076Scy** on the *ppOut pointer to free the buffer allocation following a successful 10792305002Scy** call to this function. 10793305002Scy** 10794305002Scy** WARNING/TODO: This function currently assumes that the input is a valid 10795305002Scy** changeset. If it is not, the results are undefined. 10796305002Scy*/ 10797322444SpeterSQLITE_API int sqlite3changeset_invert( 10798305002Scy int nIn, const void *pIn, /* Input changeset */ 10799305002Scy int *pnOut, void **ppOut /* OUT: Inverse of input */ 10800305002Scy); 10801305002Scy 10802305002Scy/* 10803305002Scy** CAPI3REF: Concatenate Two Changeset Objects 10804305002Scy** 10805366076Scy** This function is used to concatenate two changesets, A and B, into a 10806305002Scy** single changeset. The result is a changeset equivalent to applying 10807366076Scy** changeset A followed by changeset B. 10808305002Scy** 10809366076Scy** This function combines the two input changesets using an 10810305002Scy** sqlite3_changegroup object. Calling it produces similar results as the 10811305002Scy** following code fragment: 10812305002Scy** 10813342292Scy** <pre> 10814305002Scy** sqlite3_changegroup *pGrp; 10815305002Scy** rc = sqlite3_changegroup_new(&pGrp); 10816305002Scy** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA); 10817305002Scy** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB); 10818305002Scy** if( rc==SQLITE_OK ){ 10819305002Scy** rc = sqlite3changegroup_output(pGrp, pnOut, ppOut); 10820305002Scy** }else{ 10821305002Scy** *ppOut = 0; 10822305002Scy** *pnOut = 0; 10823305002Scy** } 10824342292Scy** </pre> 10825305002Scy** 10826305002Scy** Refer to the sqlite3_changegroup documentation below for details. 10827305002Scy*/ 10828322444SpeterSQLITE_API int sqlite3changeset_concat( 10829305002Scy int nA, /* Number of bytes in buffer pA */ 10830305002Scy void *pA, /* Pointer to buffer containing changeset A */ 10831305002Scy int nB, /* Number of bytes in buffer pB */ 10832305002Scy void *pB, /* Pointer to buffer containing changeset B */ 10833305002Scy int *pnOut, /* OUT: Number of bytes in output changeset */ 10834305002Scy void **ppOut /* OUT: Buffer containing output changeset */ 10835305002Scy); 10836305002Scy 10837305002Scy 10838305002Scy/* 10839322444Speter** CAPI3REF: Changegroup Handle 10840342292Scy** 10841366076Scy** A changegroup is an object used to combine two or more 10842342292Scy** [changesets] or [patchsets] 10843305002Scy*/ 10844305002Scytypedef struct sqlite3_changegroup sqlite3_changegroup; 10845305002Scy 10846305002Scy/* 10847322444Speter** CAPI3REF: Create A New Changegroup Object 10848342292Scy** CONSTRUCTOR: sqlite3_changegroup 10849305002Scy** 10850305002Scy** An sqlite3_changegroup object is used to combine two or more changesets 10851305002Scy** (or patchsets) into a single changeset (or patchset). A single changegroup 10852305002Scy** object may combine changesets or patchsets, but not both. The output is 10853305002Scy** always in the same format as the input. 10854305002Scy** 10855305002Scy** If successful, this function returns SQLITE_OK and populates (*pp) with 10856305002Scy** a pointer to a new sqlite3_changegroup object before returning. The caller 10857366076Scy** should eventually free the returned object using a call to 10858305002Scy** sqlite3changegroup_delete(). If an error occurs, an SQLite error code 10859305002Scy** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL. 10860305002Scy** 10861305002Scy** The usual usage pattern for an sqlite3_changegroup object is as follows: 10862305002Scy** 10863305002Scy** <ul> 10864305002Scy** <li> It is created using a call to sqlite3changegroup_new(). 10865305002Scy** 10866305002Scy** <li> Zero or more changesets (or patchsets) are added to the object 10867305002Scy** by calling sqlite3changegroup_add(). 10868305002Scy** 10869366076Scy** <li> The result of combining all input changesets together is obtained 10870305002Scy** by the application via a call to sqlite3changegroup_output(). 10871305002Scy** 10872305002Scy** <li> The object is deleted using a call to sqlite3changegroup_delete(). 10873305002Scy** </ul> 10874305002Scy** 10875305002Scy** Any number of calls to add() and output() may be made between the calls to 10876305002Scy** new() and delete(), and in any order. 10877305002Scy** 10878366076Scy** As well as the regular sqlite3changegroup_add() and 10879305002Scy** sqlite3changegroup_output() functions, also available are the streaming 10880305002Scy** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm(). 10881305002Scy*/ 10882322444SpeterSQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp); 10883305002Scy 10884305002Scy/* 10885322444Speter** CAPI3REF: Add A Changeset To A Changegroup 10886342292Scy** METHOD: sqlite3_changegroup 10887322444Speter** 10888305002Scy** Add all changes within the changeset (or patchset) in buffer pData (size 10889366076Scy** nData bytes) to the changegroup. 10890305002Scy** 10891305002Scy** If the buffer contains a patchset, then all prior calls to this function 10892305002Scy** on the same changegroup object must also have specified patchsets. Or, if 10893305002Scy** the buffer contains a changeset, so must have the earlier calls to this 10894305002Scy** function. Otherwise, SQLITE_ERROR is returned and no changes are added 10895305002Scy** to the changegroup. 10896305002Scy** 10897305002Scy** Rows within the changeset and changegroup are identified by the values in 10898305002Scy** their PRIMARY KEY columns. A change in the changeset is considered to 10899305002Scy** apply to the same row as a change already present in the changegroup if 10900305002Scy** the two rows have the same primary key. 10901305002Scy** 10902322444Speter** Changes to rows that do not already appear in the changegroup are 10903305002Scy** simply copied into it. Or, if both the new changeset and the changegroup 10904305002Scy** contain changes that apply to a single row, the final contents of the 10905305002Scy** changegroup depends on the type of each change, as follows: 10906305002Scy** 10907305002Scy** <table border=1 style="margin-left:8ex;margin-right:8ex"> 10908305002Scy** <tr><th style="white-space:pre">Existing Change </th> 10909305002Scy** <th style="white-space:pre">New Change </th> 10910305002Scy** <th>Output Change 10911305002Scy** <tr><td>INSERT <td>INSERT <td> 10912305002Scy** The new change is ignored. This case does not occur if the new 10913305002Scy** changeset was recorded immediately after the changesets already 10914305002Scy** added to the changegroup. 10915305002Scy** <tr><td>INSERT <td>UPDATE <td> 10916366076Scy** The INSERT change remains in the changegroup. The values in the 10917305002Scy** INSERT change are modified as if the row was inserted by the 10918305002Scy** existing change and then updated according to the new change. 10919305002Scy** <tr><td>INSERT <td>DELETE <td> 10920305002Scy** The existing INSERT is removed from the changegroup. The DELETE is 10921305002Scy** not added. 10922305002Scy** <tr><td>UPDATE <td>INSERT <td> 10923305002Scy** The new change is ignored. This case does not occur if the new 10924305002Scy** changeset was recorded immediately after the changesets already 10925305002Scy** added to the changegroup. 10926305002Scy** <tr><td>UPDATE <td>UPDATE <td> 10927366076Scy** The existing UPDATE remains within the changegroup. It is amended 10928366076Scy** so that the accompanying values are as if the row was updated once 10929305002Scy** by the existing change and then again by the new change. 10930305002Scy** <tr><td>UPDATE <td>DELETE <td> 10931305002Scy** The existing UPDATE is replaced by the new DELETE within the 10932305002Scy** changegroup. 10933305002Scy** <tr><td>DELETE <td>INSERT <td> 10934305002Scy** If one or more of the column values in the row inserted by the 10935366076Scy** new change differ from those in the row deleted by the existing 10936305002Scy** change, the existing DELETE is replaced by an UPDATE within the 10937366076Scy** changegroup. Otherwise, if the inserted row is exactly the same 10938305002Scy** as the deleted row, the existing DELETE is simply discarded. 10939305002Scy** <tr><td>DELETE <td>UPDATE <td> 10940305002Scy** The new change is ignored. This case does not occur if the new 10941305002Scy** changeset was recorded immediately after the changesets already 10942305002Scy** added to the changegroup. 10943305002Scy** <tr><td>DELETE <td>DELETE <td> 10944305002Scy** The new change is ignored. This case does not occur if the new 10945305002Scy** changeset was recorded immediately after the changesets already 10946305002Scy** added to the changegroup. 10947305002Scy** </table> 10948305002Scy** 10949305002Scy** If the new changeset contains changes to a table that is already present 10950305002Scy** in the changegroup, then the number of columns and the position of the 10951305002Scy** primary key columns for the table must be consistent. If this is not the 10952305002Scy** case, this function fails with SQLITE_SCHEMA. If the input changeset 10953305002Scy** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is 10954305002Scy** returned. Or, if an out-of-memory condition occurs during processing, this 10955361456Scy** function returns SQLITE_NOMEM. In all cases, if an error occurs the state 10956361456Scy** of the final contents of the changegroup is undefined. 10957305002Scy** 10958305002Scy** If no error occurs, SQLITE_OK is returned. 10959305002Scy*/ 10960322444SpeterSQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData); 10961305002Scy 10962305002Scy/* 10963322444Speter** CAPI3REF: Obtain A Composite Changeset From A Changegroup 10964342292Scy** METHOD: sqlite3_changegroup 10965322444Speter** 10966305002Scy** Obtain a buffer containing a changeset (or patchset) representing the 10967305002Scy** current contents of the changegroup. If the inputs to the changegroup 10968305002Scy** were themselves changesets, the output is a changeset. Or, if the 10969305002Scy** inputs were patchsets, the output is also a patchset. 10970305002Scy** 10971305002Scy** As with the output of the sqlite3session_changeset() and 10972305002Scy** sqlite3session_patchset() functions, all changes related to a single 10973305002Scy** table are grouped together in the output of this function. Tables appear 10974305002Scy** in the same order as for the very first changeset added to the changegroup. 10975305002Scy** If the second or subsequent changesets added to the changegroup contain 10976305002Scy** changes for tables that do not appear in the first changeset, they are 10977305002Scy** appended onto the end of the output changeset, again in the order in 10978305002Scy** which they are first encountered. 10979305002Scy** 10980305002Scy** If an error occurs, an SQLite error code is returned and the output 10981305002Scy** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK 10982366076Scy** is returned and the output variables are set to the size of and a 10983305002Scy** pointer to the output buffer, respectively. In this case it is the 10984305002Scy** responsibility of the caller to eventually free the buffer using a 10985305002Scy** call to sqlite3_free(). 10986305002Scy*/ 10987322444SpeterSQLITE_API int sqlite3changegroup_output( 10988305002Scy sqlite3_changegroup*, 10989305002Scy int *pnData, /* OUT: Size of output buffer in bytes */ 10990305002Scy void **ppData /* OUT: Pointer to output buffer */ 10991305002Scy); 10992305002Scy 10993305002Scy/* 10994322444Speter** CAPI3REF: Delete A Changegroup Object 10995342292Scy** DESTRUCTOR: sqlite3_changegroup 10996305002Scy*/ 10997322444SpeterSQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*); 10998305002Scy 10999305002Scy/* 11000305002Scy** CAPI3REF: Apply A Changeset To A Database 11001305002Scy** 11002342292Scy** Apply a changeset or patchset to a database. These functions attempt to 11003342292Scy** update the "main" database attached to handle db with the changes found in 11004366076Scy** the changeset passed via the second and third arguments. 11005305002Scy** 11006342292Scy** The fourth argument (xFilter) passed to these functions is the "filter 11007305002Scy** callback". If it is not NULL, then for each table affected by at least one 11008305002Scy** change in the changeset, the filter callback is invoked with 11009305002Scy** the table name as the second argument, and a copy of the context pointer 11010342292Scy** passed as the sixth argument as the first. If the "filter callback" 11011342292Scy** returns zero, then no attempt is made to apply any changes to the table. 11012342292Scy** Otherwise, if the return value is non-zero or the xFilter argument to 11013342292Scy** is NULL, all changes related to the table are attempted. 11014305002Scy** 11015366076Scy** For each table that is not excluded by the filter callback, this function 11016366076Scy** tests that the target database contains a compatible table. A table is 11017305002Scy** considered compatible if all of the following are true: 11018305002Scy** 11019305002Scy** <ul> 11020366076Scy** <li> The table has the same name as the name recorded in the 11021305002Scy** changeset, and 11022366076Scy** <li> The table has at least as many columns as recorded in the 11023305002Scy** changeset, and 11024366076Scy** <li> The table has primary key columns in the same position as 11025305002Scy** recorded in the changeset. 11026305002Scy** </ul> 11027305002Scy** 11028305002Scy** If there is no compatible table, it is not an error, but none of the 11029305002Scy** changes associated with the table are applied. A warning message is issued 11030305002Scy** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most 11031305002Scy** one such warning is issued for each table in the changeset. 11032305002Scy** 11033366076Scy** For each change for which there is a compatible table, an attempt is made 11034366076Scy** to modify the table contents according to the UPDATE, INSERT or DELETE 11035366076Scy** change. If a change cannot be applied cleanly, the conflict handler 11036366076Scy** function passed as the fifth argument to sqlite3changeset_apply() may be 11037366076Scy** invoked. A description of exactly when the conflict handler is invoked for 11038305002Scy** each type of change is below. 11039305002Scy** 11040305002Scy** Unlike the xFilter argument, xConflict may not be passed NULL. The results 11041305002Scy** of passing anything other than a valid function pointer as the xConflict 11042305002Scy** argument are undefined. 11043305002Scy** 11044305002Scy** Each time the conflict handler function is invoked, it must return one 11045366076Scy** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or 11046305002Scy** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned 11047305002Scy** if the second argument passed to the conflict handler is either 11048305002Scy** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler 11049305002Scy** returns an illegal value, any changes already made are rolled back and 11050366076Scy** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different 11051305002Scy** actions are taken by sqlite3changeset_apply() depending on the value 11052305002Scy** returned by each invocation of the conflict-handler function. Refer to 11053366076Scy** the documentation for the three 11054305002Scy** [SQLITE_CHANGESET_OMIT|available return values] for details. 11055305002Scy** 11056305002Scy** <dl> 11057305002Scy** <dt>DELETE Changes<dd> 11058366076Scy** For each DELETE change, the function checks if the target database 11059366076Scy** contains a row with the same primary key value (or values) as the 11060366076Scy** original row values stored in the changeset. If it does, and the values 11061366076Scy** stored in all non-primary key columns also match the values stored in 11062305002Scy** the changeset the row is deleted from the target database. 11063305002Scy** 11064305002Scy** If a row with matching primary key values is found, but one or more of 11065305002Scy** the non-primary key fields contains a value different from the original 11066305002Scy** row value stored in the changeset, the conflict-handler function is 11067322444Speter** invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the 11068322444Speter** database table has more columns than are recorded in the changeset, 11069322444Speter** only the values of those non-primary key fields are compared against 11070322444Speter** the current database contents - any trailing database table columns 11071322444Speter** are ignored. 11072305002Scy** 11073305002Scy** If no row with matching primary key values is found in the database, 11074305002Scy** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] 11075305002Scy** passed as the second argument. 11076305002Scy** 11077305002Scy** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT 11078305002Scy** (which can only happen if a foreign key constraint is violated), the 11079305002Scy** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT] 11080305002Scy** passed as the second argument. This includes the case where the DELETE 11081305002Scy** operation is attempted because an earlier call to the conflict handler 11082305002Scy** function returned [SQLITE_CHANGESET_REPLACE]. 11083305002Scy** 11084305002Scy** <dt>INSERT Changes<dd> 11085305002Scy** For each INSERT change, an attempt is made to insert the new row into 11086322444Speter** the database. If the changeset row contains fewer fields than the 11087322444Speter** database table, the trailing fields are populated with their default 11088322444Speter** values. 11089305002Scy** 11090366076Scy** If the attempt to insert the row fails because the database already 11091305002Scy** contains a row with the same primary key values, the conflict handler 11092366076Scy** function is invoked with the second argument set to 11093305002Scy** [SQLITE_CHANGESET_CONFLICT]. 11094305002Scy** 11095305002Scy** If the attempt to insert the row fails because of some other constraint 11096366076Scy** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is 11097305002Scy** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT]. 11098366076Scy** This includes the case where the INSERT operation is re-attempted because 11099366076Scy** an earlier call to the conflict handler function returned 11100305002Scy** [SQLITE_CHANGESET_REPLACE]. 11101305002Scy** 11102305002Scy** <dt>UPDATE Changes<dd> 11103366076Scy** For each UPDATE change, the function checks if the target database 11104366076Scy** contains a row with the same primary key value (or values) as the 11105366076Scy** original row values stored in the changeset. If it does, and the values 11106322444Speter** stored in all modified non-primary key columns also match the values 11107322444Speter** stored in the changeset the row is updated within the target database. 11108305002Scy** 11109305002Scy** If a row with matching primary key values is found, but one or more of 11110322444Speter** the modified non-primary key fields contains a value different from an 11111322444Speter** original row value stored in the changeset, the conflict-handler function 11112322444Speter** is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since 11113305002Scy** UPDATE changes only contain values for non-primary key fields that are 11114305002Scy** to be modified, only those fields need to match the original values to 11115305002Scy** avoid the SQLITE_CHANGESET_DATA conflict-handler callback. 11116305002Scy** 11117305002Scy** If no row with matching primary key values is found in the database, 11118305002Scy** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] 11119305002Scy** passed as the second argument. 11120305002Scy** 11121366076Scy** If the UPDATE operation is attempted, but SQLite returns 11122366076Scy** SQLITE_CONSTRAINT, the conflict-handler function is invoked with 11123305002Scy** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument. 11124366076Scy** This includes the case where the UPDATE operation is attempted after 11125305002Scy** an earlier call to the conflict handler function returned 11126366076Scy** [SQLITE_CHANGESET_REPLACE]. 11127305002Scy** </dl> 11128305002Scy** 11129305002Scy** It is safe to execute SQL statements, including those that write to the 11130305002Scy** table that the callback related to, from within the xConflict callback. 11131361456Scy** This can be used to further customize the application's conflict 11132305002Scy** resolution strategy. 11133305002Scy** 11134342292Scy** All changes made by these functions are enclosed in a savepoint transaction. 11135305002Scy** If any other error (aside from a constraint failure when attempting to 11136305002Scy** write to the target database) occurs, then the savepoint transaction is 11137366076Scy** rolled back, restoring the target database to its original state, and an 11138305002Scy** SQLite error code returned. 11139342292Scy** 11140342292Scy** If the output parameters (ppRebase) and (pnRebase) are non-NULL and 11141342292Scy** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2() 11142366076Scy** may set (*ppRebase) to point to a "rebase" that may be used with the 11143342292Scy** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase) 11144342292Scy** is set to the size of the buffer in bytes. It is the responsibility of the 11145342292Scy** caller to eventually free any such buffer using sqlite3_free(). The buffer 11146342292Scy** is only allocated and populated if one or more conflicts were encountered 11147342292Scy** while applying the patchset. See comments surrounding the sqlite3_rebaser 11148342292Scy** APIs for further details. 11149342292Scy** 11150342292Scy** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent 11151342292Scy** may be modified by passing a combination of 11152342292Scy** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter. 11153342292Scy** 11154342292Scy** Note that the sqlite3changeset_apply_v2() API is still <b>experimental</b> 11155342292Scy** and therefore subject to change. 11156305002Scy*/ 11157322444SpeterSQLITE_API int sqlite3changeset_apply( 11158305002Scy sqlite3 *db, /* Apply change to "main" db of this handle */ 11159305002Scy int nChangeset, /* Size of changeset in bytes */ 11160305002Scy void *pChangeset, /* Changeset blob */ 11161305002Scy int(*xFilter)( 11162305002Scy void *pCtx, /* Copy of sixth arg to _apply() */ 11163305002Scy const char *zTab /* Table name */ 11164305002Scy ), 11165305002Scy int(*xConflict)( 11166305002Scy void *pCtx, /* Copy of sixth arg to _apply() */ 11167305002Scy int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 11168305002Scy sqlite3_changeset_iter *p /* Handle describing change and conflict */ 11169305002Scy ), 11170305002Scy void *pCtx /* First argument passed to xConflict */ 11171305002Scy); 11172342292ScySQLITE_API int sqlite3changeset_apply_v2( 11173342292Scy sqlite3 *db, /* Apply change to "main" db of this handle */ 11174342292Scy int nChangeset, /* Size of changeset in bytes */ 11175342292Scy void *pChangeset, /* Changeset blob */ 11176342292Scy int(*xFilter)( 11177342292Scy void *pCtx, /* Copy of sixth arg to _apply() */ 11178342292Scy const char *zTab /* Table name */ 11179342292Scy ), 11180342292Scy int(*xConflict)( 11181342292Scy void *pCtx, /* Copy of sixth arg to _apply() */ 11182342292Scy int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 11183342292Scy sqlite3_changeset_iter *p /* Handle describing change and conflict */ 11184342292Scy ), 11185342292Scy void *pCtx, /* First argument passed to xConflict */ 11186342292Scy void **ppRebase, int *pnRebase, /* OUT: Rebase data */ 11187342292Scy int flags /* SESSION_CHANGESETAPPLY_* flags */ 11188342292Scy); 11189305002Scy 11190342292Scy/* 11191342292Scy** CAPI3REF: Flags for sqlite3changeset_apply_v2 11192342292Scy** 11193342292Scy** The following flags may passed via the 9th parameter to 11194342292Scy** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]: 11195342292Scy** 11196342292Scy** <dl> 11197342292Scy** <dt>SQLITE_CHANGESETAPPLY_NOSAVEPOINT <dd> 11198342292Scy** Usually, the sessions module encloses all operations performed by 11199342292Scy** a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The 11200342292Scy** SAVEPOINT is committed if the changeset or patchset is successfully 11201342292Scy** applied, or rolled back if an error occurs. Specifying this flag 11202342292Scy** causes the sessions module to omit this savepoint. In this case, if the 11203366076Scy** caller has an open transaction or savepoint when apply_v2() is called, 11204342292Scy** it may revert the partially applied changeset by rolling it back. 11205342292Scy** 11206342292Scy** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd> 11207342292Scy** Invert the changeset before applying it. This is equivalent to inverting 11208342292Scy** a changeset using sqlite3changeset_invert() before applying it. It is 11209342292Scy** an error to specify this flag with a patchset. 11210342292Scy*/ 11211342292Scy#define SQLITE_CHANGESETAPPLY_NOSAVEPOINT 0x0001 11212342292Scy#define SQLITE_CHANGESETAPPLY_INVERT 0x0002 11213342292Scy 11214366076Scy/* 11215305002Scy** CAPI3REF: Constants Passed To The Conflict Handler 11216305002Scy** 11217305002Scy** Values that may be passed as the second argument to a conflict-handler. 11218305002Scy** 11219305002Scy** <dl> 11220305002Scy** <dt>SQLITE_CHANGESET_DATA<dd> 11221305002Scy** The conflict handler is invoked with CHANGESET_DATA as the second argument 11222305002Scy** when processing a DELETE or UPDATE change if a row with the required 11223366076Scy** PRIMARY KEY fields is present in the database, but one or more other 11224366076Scy** (non primary-key) fields modified by the update do not contain the 11225305002Scy** expected "before" values. 11226366076Scy** 11227305002Scy** The conflicting row, in this case, is the database row with the matching 11228305002Scy** primary key. 11229366076Scy** 11230305002Scy** <dt>SQLITE_CHANGESET_NOTFOUND<dd> 11231305002Scy** The conflict handler is invoked with CHANGESET_NOTFOUND as the second 11232305002Scy** argument when processing a DELETE or UPDATE change if a row with the 11233305002Scy** required PRIMARY KEY fields is not present in the database. 11234366076Scy** 11235305002Scy** There is no conflicting row in this case. The results of invoking the 11236305002Scy** sqlite3changeset_conflict() API are undefined. 11237366076Scy** 11238305002Scy** <dt>SQLITE_CHANGESET_CONFLICT<dd> 11239305002Scy** CHANGESET_CONFLICT is passed as the second argument to the conflict 11240366076Scy** handler while processing an INSERT change if the operation would result 11241305002Scy** in duplicate primary key values. 11242366076Scy** 11243305002Scy** The conflicting row in this case is the database row with the matching 11244305002Scy** primary key. 11245305002Scy** 11246305002Scy** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd> 11247305002Scy** If foreign key handling is enabled, and applying a changeset leaves the 11248366076Scy** database in a state containing foreign key violations, the conflict 11249305002Scy** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument 11250305002Scy** exactly once before the changeset is committed. If the conflict handler 11251305002Scy** returns CHANGESET_OMIT, the changes, including those that caused the 11252305002Scy** foreign key constraint violation, are committed. Or, if it returns 11253305002Scy** CHANGESET_ABORT, the changeset is rolled back. 11254305002Scy** 11255305002Scy** No current or conflicting row information is provided. The only function 11256305002Scy** it is possible to call on the supplied sqlite3_changeset_iter handle 11257305002Scy** is sqlite3changeset_fk_conflicts(). 11258366076Scy** 11259305002Scy** <dt>SQLITE_CHANGESET_CONSTRAINT<dd> 11260366076Scy** If any other constraint violation occurs while applying a change (i.e. 11261366076Scy** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is 11262305002Scy** invoked with CHANGESET_CONSTRAINT as the second argument. 11263366076Scy** 11264305002Scy** There is no conflicting row in this case. The results of invoking the 11265305002Scy** sqlite3changeset_conflict() API are undefined. 11266305002Scy** 11267305002Scy** </dl> 11268305002Scy*/ 11269305002Scy#define SQLITE_CHANGESET_DATA 1 11270305002Scy#define SQLITE_CHANGESET_NOTFOUND 2 11271305002Scy#define SQLITE_CHANGESET_CONFLICT 3 11272305002Scy#define SQLITE_CHANGESET_CONSTRAINT 4 11273305002Scy#define SQLITE_CHANGESET_FOREIGN_KEY 5 11274305002Scy 11275366076Scy/* 11276305002Scy** CAPI3REF: Constants Returned By The Conflict Handler 11277305002Scy** 11278305002Scy** A conflict handler callback must return one of the following three values. 11279305002Scy** 11280305002Scy** <dl> 11281305002Scy** <dt>SQLITE_CHANGESET_OMIT<dd> 11282305002Scy** If a conflict handler returns this value no special action is taken. The 11283366076Scy** change that caused the conflict is not applied. The session module 11284305002Scy** continues to the next change in the changeset. 11285305002Scy** 11286305002Scy** <dt>SQLITE_CHANGESET_REPLACE<dd> 11287305002Scy** This value may only be returned if the second argument to the conflict 11288305002Scy** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this 11289366076Scy** is not the case, any changes applied so far are rolled back and the 11290305002Scy** call to sqlite3changeset_apply() returns SQLITE_MISUSE. 11291305002Scy** 11292305002Scy** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict 11293305002Scy** handler, then the conflicting row is either updated or deleted, depending 11294305002Scy** on the type of change. 11295305002Scy** 11296305002Scy** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict 11297305002Scy** handler, then the conflicting row is removed from the database and a 11298305002Scy** second attempt to apply the change is made. If this second attempt fails, 11299305002Scy** the original row is restored to the database before continuing. 11300305002Scy** 11301305002Scy** <dt>SQLITE_CHANGESET_ABORT<dd> 11302366076Scy** If this value is returned, any changes applied so far are rolled back 11303305002Scy** and the call to sqlite3changeset_apply() returns SQLITE_ABORT. 11304305002Scy** </dl> 11305305002Scy*/ 11306305002Scy#define SQLITE_CHANGESET_OMIT 0 11307305002Scy#define SQLITE_CHANGESET_REPLACE 1 11308305002Scy#define SQLITE_CHANGESET_ABORT 2 11309305002Scy 11310366076Scy/* 11311342292Scy** CAPI3REF: Rebasing changesets 11312342292Scy** EXPERIMENTAL 11313342292Scy** 11314342292Scy** Suppose there is a site hosting a database in state S0. And that 11315342292Scy** modifications are made that move that database to state S1 and a 11316342292Scy** changeset recorded (the "local" changeset). Then, a changeset based 11317366076Scy** on S0 is received from another site (the "remote" changeset) and 11318366076Scy** applied to the database. The database is then in state 11319342292Scy** (S1+"remote"), where the exact state depends on any conflict 11320342292Scy** resolution decisions (OMIT or REPLACE) made while applying "remote". 11321366076Scy** Rebasing a changeset is to update it to take those conflict 11322342292Scy** resolution decisions into account, so that the same conflicts 11323366076Scy** do not have to be resolved elsewhere in the network. 11324342292Scy** 11325342292Scy** For example, if both the local and remote changesets contain an 11326342292Scy** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)": 11327342292Scy** 11328342292Scy** local: INSERT INTO t1 VALUES(1, 'v1'); 11329342292Scy** remote: INSERT INTO t1 VALUES(1, 'v2'); 11330342292Scy** 11331342292Scy** and the conflict resolution is REPLACE, then the INSERT change is 11332342292Scy** removed from the local changeset (it was overridden). Or, if the 11333342292Scy** conflict resolution was "OMIT", then the local changeset is modified 11334342292Scy** to instead contain: 11335342292Scy** 11336342292Scy** UPDATE t1 SET b = 'v2' WHERE a=1; 11337342292Scy** 11338342292Scy** Changes within the local changeset are rebased as follows: 11339342292Scy** 11340342292Scy** <dl> 11341342292Scy** <dt>Local INSERT<dd> 11342366076Scy** This may only conflict with a remote INSERT. If the conflict 11343342292Scy** resolution was OMIT, then add an UPDATE change to the rebased 11344342292Scy** changeset. Or, if the conflict resolution was REPLACE, add 11345342292Scy** nothing to the rebased changeset. 11346342292Scy** 11347342292Scy** <dt>Local DELETE<dd> 11348342292Scy** This may conflict with a remote UPDATE or DELETE. In both cases the 11349342292Scy** only possible resolution is OMIT. If the remote operation was a 11350342292Scy** DELETE, then add no change to the rebased changeset. If the remote 11351342292Scy** operation was an UPDATE, then the old.* fields of change are updated 11352342292Scy** to reflect the new.* values in the UPDATE. 11353342292Scy** 11354342292Scy** <dt>Local UPDATE<dd> 11355342292Scy** This may conflict with a remote UPDATE or DELETE. If it conflicts 11356342292Scy** with a DELETE, and the conflict resolution was OMIT, then the update 11357342292Scy** is changed into an INSERT. Any undefined values in the new.* record 11358342292Scy** from the update change are filled in using the old.* values from 11359342292Scy** the conflicting DELETE. Or, if the conflict resolution was REPLACE, 11360342292Scy** the UPDATE change is simply omitted from the rebased changeset. 11361342292Scy** 11362342292Scy** If conflict is with a remote UPDATE and the resolution is OMIT, then 11363342292Scy** the old.* values are rebased using the new.* values in the remote 11364342292Scy** change. Or, if the resolution is REPLACE, then the change is copied 11365342292Scy** into the rebased changeset with updates to columns also updated by 11366366076Scy** the conflicting remote UPDATE removed. If this means no columns would 11367342292Scy** be updated, the change is omitted. 11368342292Scy** </dl> 11369342292Scy** 11370366076Scy** A local change may be rebased against multiple remote changes 11371366076Scy** simultaneously. If a single key is modified by multiple remote 11372342292Scy** changesets, they are combined as follows before the local changeset 11373342292Scy** is rebased: 11374342292Scy** 11375342292Scy** <ul> 11376342292Scy** <li> If there has been one or more REPLACE resolutions on a 11377342292Scy** key, it is rebased according to a REPLACE. 11378342292Scy** 11379342292Scy** <li> If there have been no REPLACE resolutions on a key, then 11380342292Scy** the local changeset is rebased according to the most recent 11381342292Scy** of the OMIT resolutions. 11382342292Scy** </ul> 11383342292Scy** 11384366076Scy** Note that conflict resolutions from multiple remote changesets are 11385366076Scy** combined on a per-field basis, not per-row. This means that in the 11386366076Scy** case of multiple remote UPDATE operations, some fields of a single 11387366076Scy** local change may be rebased for REPLACE while others are rebased for 11388342292Scy** OMIT. 11389342292Scy** 11390342292Scy** In order to rebase a local changeset, the remote changeset must first 11391342292Scy** be applied to the local database using sqlite3changeset_apply_v2() and 11392342292Scy** the buffer of rebase information captured. Then: 11393342292Scy** 11394342292Scy** <ol> 11395366076Scy** <li> An sqlite3_rebaser object is created by calling 11396342292Scy** sqlite3rebaser_create(). 11397342292Scy** <li> The new object is configured with the rebase buffer obtained from 11398342292Scy** sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure(). 11399342292Scy** If the local changeset is to be rebased against multiple remote 11400342292Scy** changesets, then sqlite3rebaser_configure() should be called 11401342292Scy** multiple times, in the same order that the multiple 11402342292Scy** sqlite3changeset_apply_v2() calls were made. 11403342292Scy** <li> Each local changeset is rebased by calling sqlite3rebaser_rebase(). 11404342292Scy** <li> The sqlite3_rebaser object is deleted by calling 11405342292Scy** sqlite3rebaser_delete(). 11406342292Scy** </ol> 11407342292Scy*/ 11408342292Scytypedef struct sqlite3_rebaser sqlite3_rebaser; 11409342292Scy 11410305002Scy/* 11411342292Scy** CAPI3REF: Create a changeset rebaser object. 11412342292Scy** EXPERIMENTAL 11413342292Scy** 11414342292Scy** Allocate a new changeset rebaser object. If successful, set (*ppNew) to 11415342292Scy** point to the new object and return SQLITE_OK. Otherwise, if an error 11416366076Scy** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew) 11417366076Scy** to NULL. 11418342292Scy*/ 11419342292ScySQLITE_API int sqlite3rebaser_create(sqlite3_rebaser **ppNew); 11420342292Scy 11421342292Scy/* 11422342292Scy** CAPI3REF: Configure a changeset rebaser object. 11423342292Scy** EXPERIMENTAL 11424342292Scy** 11425342292Scy** Configure the changeset rebaser object to rebase changesets according 11426342292Scy** to the conflict resolutions described by buffer pRebase (size nRebase 11427342292Scy** bytes), which must have been obtained from a previous call to 11428342292Scy** sqlite3changeset_apply_v2(). 11429342292Scy*/ 11430342292ScySQLITE_API int sqlite3rebaser_configure( 11431366076Scy sqlite3_rebaser*, 11432342292Scy int nRebase, const void *pRebase 11433366076Scy); 11434342292Scy 11435342292Scy/* 11436342292Scy** CAPI3REF: Rebase a changeset 11437342292Scy** EXPERIMENTAL 11438342292Scy** 11439342292Scy** Argument pIn must point to a buffer containing a changeset nIn bytes 11440342292Scy** in size. This function allocates and populates a buffer with a copy 11441361456Scy** of the changeset rebased according to the configuration of the 11442342292Scy** rebaser object passed as the first argument. If successful, (*ppOut) 11443366076Scy** is set to point to the new buffer containing the rebased changeset and 11444342292Scy** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the 11445342292Scy** responsibility of the caller to eventually free the new buffer using 11446342292Scy** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut) 11447342292Scy** are set to zero and an SQLite error code returned. 11448342292Scy*/ 11449342292ScySQLITE_API int sqlite3rebaser_rebase( 11450342292Scy sqlite3_rebaser*, 11451366076Scy int nIn, const void *pIn, 11452366076Scy int *pnOut, void **ppOut 11453342292Scy); 11454342292Scy 11455342292Scy/* 11456342292Scy** CAPI3REF: Delete a changeset rebaser object. 11457342292Scy** EXPERIMENTAL 11458342292Scy** 11459342292Scy** Delete the changeset rebaser object and all associated resources. There 11460342292Scy** should be one call to this function for each successful invocation 11461342292Scy** of sqlite3rebaser_create(). 11462342292Scy*/ 11463366076ScySQLITE_API void sqlite3rebaser_delete(sqlite3_rebaser *p); 11464342292Scy 11465342292Scy/* 11466305002Scy** CAPI3REF: Streaming Versions of API functions. 11467305002Scy** 11468366076Scy** The six streaming API xxx_strm() functions serve similar purposes to the 11469305002Scy** corresponding non-streaming API functions: 11470305002Scy** 11471305002Scy** <table border=1 style="margin-left:8ex;margin-right:8ex"> 11472305002Scy** <tr><th>Streaming function<th>Non-streaming equivalent</th> 11473366076Scy** <tr><td>sqlite3changeset_apply_strm<td>[sqlite3changeset_apply] 11474366076Scy** <tr><td>sqlite3changeset_apply_strm_v2<td>[sqlite3changeset_apply_v2] 11475366076Scy** <tr><td>sqlite3changeset_concat_strm<td>[sqlite3changeset_concat] 11476366076Scy** <tr><td>sqlite3changeset_invert_strm<td>[sqlite3changeset_invert] 11477366076Scy** <tr><td>sqlite3changeset_start_strm<td>[sqlite3changeset_start] 11478366076Scy** <tr><td>sqlite3session_changeset_strm<td>[sqlite3session_changeset] 11479366076Scy** <tr><td>sqlite3session_patchset_strm<td>[sqlite3session_patchset] 11480305002Scy** </table> 11481305002Scy** 11482305002Scy** Non-streaming functions that accept changesets (or patchsets) as input 11483366076Scy** require that the entire changeset be stored in a single buffer in memory. 11484366076Scy** Similarly, those that return a changeset or patchset do so by returning 11485366076Scy** a pointer to a single large buffer allocated using sqlite3_malloc(). 11486366076Scy** Normally this is convenient. However, if an application running in a 11487305002Scy** low-memory environment is required to handle very large changesets, the 11488305002Scy** large contiguous memory allocations required can become onerous. 11489305002Scy** 11490305002Scy** In order to avoid this problem, instead of a single large buffer, input 11491305002Scy** is passed to a streaming API functions by way of a callback function that 11492305002Scy** the sessions module invokes to incrementally request input data as it is 11493305002Scy** required. In all cases, a pair of API function parameters such as 11494305002Scy** 11495305002Scy** <pre> 11496305002Scy** int nChangeset, 11497305002Scy** void *pChangeset, 11498305002Scy** </pre> 11499305002Scy** 11500305002Scy** Is replaced by: 11501305002Scy** 11502305002Scy** <pre> 11503305002Scy** int (*xInput)(void *pIn, void *pData, int *pnData), 11504305002Scy** void *pIn, 11505305002Scy** </pre> 11506305002Scy** 11507305002Scy** Each time the xInput callback is invoked by the sessions module, the first 11508366076Scy** argument passed is a copy of the supplied pIn context pointer. The second 11509366076Scy** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no 11510366076Scy** error occurs the xInput method should copy up to (*pnData) bytes of data 11511366076Scy** into the buffer and set (*pnData) to the actual number of bytes copied 11512366076Scy** before returning SQLITE_OK. If the input is completely exhausted, (*pnData) 11513366076Scy** should be set to zero to indicate this. Or, if an error occurs, an SQLite 11514305002Scy** error code should be returned. In all cases, if an xInput callback returns 11515305002Scy** an error, all processing is abandoned and the streaming API function 11516305002Scy** returns a copy of the error code to the caller. 11517305002Scy** 11518305002Scy** In the case of sqlite3changeset_start_strm(), the xInput callback may be 11519305002Scy** invoked by the sessions module at any point during the lifetime of the 11520305002Scy** iterator. If such an xInput callback returns an error, the iterator enters 11521366076Scy** an error state, whereby all subsequent calls to iterator functions 11522305002Scy** immediately fail with the same error code as returned by xInput. 11523305002Scy** 11524305002Scy** Similarly, streaming API functions that return changesets (or patchsets) 11525305002Scy** return them in chunks by way of a callback function instead of via a 11526305002Scy** pointer to a single large buffer. In this case, a pair of parameters such 11527305002Scy** as: 11528305002Scy** 11529305002Scy** <pre> 11530305002Scy** int *pnChangeset, 11531305002Scy** void **ppChangeset, 11532305002Scy** </pre> 11533305002Scy** 11534305002Scy** Is replaced by: 11535305002Scy** 11536305002Scy** <pre> 11537305002Scy** int (*xOutput)(void *pOut, const void *pData, int nData), 11538305002Scy** void *pOut 11539305002Scy** </pre> 11540305002Scy** 11541305002Scy** The xOutput callback is invoked zero or more times to return data to 11542305002Scy** the application. The first parameter passed to each call is a copy of the 11543305002Scy** pOut pointer supplied by the application. The second parameter, pData, 11544305002Scy** points to a buffer nData bytes in size containing the chunk of output 11545305002Scy** data being returned. If the xOutput callback successfully processes the 11546305002Scy** supplied data, it should return SQLITE_OK to indicate success. Otherwise, 11547305002Scy** it should return some other SQLite error code. In this case processing 11548305002Scy** is immediately abandoned and the streaming API function returns a copy 11549305002Scy** of the xOutput error code to the application. 11550305002Scy** 11551366076Scy** The sessions module never invokes an xOutput callback with the third 11552305002Scy** parameter set to a value less than or equal to zero. Other than this, 11553305002Scy** no guarantees are made as to the size of the chunks of data returned. 11554305002Scy*/ 11555322444SpeterSQLITE_API int sqlite3changeset_apply_strm( 11556305002Scy sqlite3 *db, /* Apply change to "main" db of this handle */ 11557305002Scy int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ 11558305002Scy void *pIn, /* First arg for xInput */ 11559305002Scy int(*xFilter)( 11560305002Scy void *pCtx, /* Copy of sixth arg to _apply() */ 11561305002Scy const char *zTab /* Table name */ 11562305002Scy ), 11563305002Scy int(*xConflict)( 11564305002Scy void *pCtx, /* Copy of sixth arg to _apply() */ 11565305002Scy int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 11566305002Scy sqlite3_changeset_iter *p /* Handle describing change and conflict */ 11567305002Scy ), 11568305002Scy void *pCtx /* First argument passed to xConflict */ 11569305002Scy); 11570342292ScySQLITE_API int sqlite3changeset_apply_v2_strm( 11571342292Scy sqlite3 *db, /* Apply change to "main" db of this handle */ 11572342292Scy int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ 11573342292Scy void *pIn, /* First arg for xInput */ 11574342292Scy int(*xFilter)( 11575342292Scy void *pCtx, /* Copy of sixth arg to _apply() */ 11576342292Scy const char *zTab /* Table name */ 11577342292Scy ), 11578342292Scy int(*xConflict)( 11579342292Scy void *pCtx, /* Copy of sixth arg to _apply() */ 11580342292Scy int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 11581342292Scy sqlite3_changeset_iter *p /* Handle describing change and conflict */ 11582342292Scy ), 11583342292Scy void *pCtx, /* First argument passed to xConflict */ 11584342292Scy void **ppRebase, int *pnRebase, 11585342292Scy int flags 11586342292Scy); 11587322444SpeterSQLITE_API int sqlite3changeset_concat_strm( 11588305002Scy int (*xInputA)(void *pIn, void *pData, int *pnData), 11589305002Scy void *pInA, 11590305002Scy int (*xInputB)(void *pIn, void *pData, int *pnData), 11591305002Scy void *pInB, 11592305002Scy int (*xOutput)(void *pOut, const void *pData, int nData), 11593305002Scy void *pOut 11594305002Scy); 11595322444SpeterSQLITE_API int sqlite3changeset_invert_strm( 11596305002Scy int (*xInput)(void *pIn, void *pData, int *pnData), 11597305002Scy void *pIn, 11598305002Scy int (*xOutput)(void *pOut, const void *pData, int nData), 11599305002Scy void *pOut 11600305002Scy); 11601322444SpeterSQLITE_API int sqlite3changeset_start_strm( 11602305002Scy sqlite3_changeset_iter **pp, 11603305002Scy int (*xInput)(void *pIn, void *pData, int *pnData), 11604305002Scy void *pIn 11605305002Scy); 11606342292ScySQLITE_API int sqlite3changeset_start_v2_strm( 11607342292Scy sqlite3_changeset_iter **pp, 11608342292Scy int (*xInput)(void *pIn, void *pData, int *pnData), 11609342292Scy void *pIn, 11610342292Scy int flags 11611342292Scy); 11612322444SpeterSQLITE_API int sqlite3session_changeset_strm( 11613305002Scy sqlite3_session *pSession, 11614305002Scy int (*xOutput)(void *pOut, const void *pData, int nData), 11615305002Scy void *pOut 11616305002Scy); 11617322444SpeterSQLITE_API int sqlite3session_patchset_strm( 11618305002Scy sqlite3_session *pSession, 11619305002Scy int (*xOutput)(void *pOut, const void *pData, int nData), 11620305002Scy void *pOut 11621305002Scy); 11622366076ScySQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*, 11623305002Scy int (*xInput)(void *pIn, void *pData, int *pnData), 11624305002Scy void *pIn 11625305002Scy); 11626322444SpeterSQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*, 11627366076Scy int (*xOutput)(void *pOut, const void *pData, int nData), 11628305002Scy void *pOut 11629305002Scy); 11630342292ScySQLITE_API int sqlite3rebaser_rebase_strm( 11631342292Scy sqlite3_rebaser *pRebaser, 11632342292Scy int (*xInput)(void *pIn, void *pData, int *pnData), 11633342292Scy void *pIn, 11634342292Scy int (*xOutput)(void *pOut, const void *pData, int nData), 11635342292Scy void *pOut 11636342292Scy); 11637305002Scy 11638342292Scy/* 11639342292Scy** CAPI3REF: Configure global parameters 11640342292Scy** 11641342292Scy** The sqlite3session_config() interface is used to make global configuration 11642366076Scy** changes to the sessions module in order to tune it to the specific needs 11643342292Scy** of the application. 11644342292Scy** 11645342292Scy** The sqlite3session_config() interface is not threadsafe. If it is invoked 11646342292Scy** while any other thread is inside any other sessions method then the 11647342292Scy** results are undefined. Furthermore, if it is invoked after any sessions 11648366076Scy** related objects have been created, the results are also undefined. 11649342292Scy** 11650342292Scy** The first argument to the sqlite3session_config() function must be one 11651366076Scy** of the SQLITE_SESSION_CONFIG_XXX constants defined below. The 11652342292Scy** interpretation of the (void*) value passed as the second parameter and 11653342292Scy** the effect of calling this function depends on the value of the first 11654342292Scy** parameter. 11655342292Scy** 11656342292Scy** <dl> 11657342292Scy** <dt>SQLITE_SESSION_CONFIG_STRMSIZE<dd> 11658342292Scy** By default, the sessions module streaming interfaces attempt to input 11659342292Scy** and output data in approximately 1 KiB chunks. This operand may be used 11660342292Scy** to set and query the value of this configuration setting. The pointer 11661342292Scy** passed as the second argument must point to a value of type (int). 11662342292Scy** If this value is greater than 0, it is used as the new streaming data 11663342292Scy** chunk size for both input and output. Before returning, the (int) value 11664342292Scy** pointed to by pArg is set to the final value of the streaming interface 11665342292Scy** chunk size. 11666342292Scy** </dl> 11667342292Scy** 11668342292Scy** This function returns SQLITE_OK if successful, or an SQLite error code 11669342292Scy** otherwise. 11670342292Scy*/ 11671342292ScySQLITE_API int sqlite3session_config(int op, void *pArg); 11672305002Scy 11673305002Scy/* 11674342292Scy** CAPI3REF: Values for sqlite3session_config(). 11675342292Scy*/ 11676342292Scy#define SQLITE_SESSION_CONFIG_STRMSIZE 1 11677342292Scy 11678342292Scy/* 11679305002Scy** Make sure we can call this stuff from C++. 11680305002Scy*/ 11681305002Scy#ifdef __cplusplus 11682305002Scy} 11683305002Scy#endif 11684305002Scy 11685305002Scy#endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */ 11686305002Scy 11687305002Scy/******** End of sqlite3session.h *********/ 11688305002Scy/******** Begin file fts5.h *********/ 11689305002Scy/* 11690298161Sbapt** 2014 May 31 11691298161Sbapt** 11692298161Sbapt** The author disclaims copyright to this source code. In place of 11693298161Sbapt** a legal notice, here is a blessing: 11694298161Sbapt** 11695298161Sbapt** May you do good and not evil. 11696298161Sbapt** May you find forgiveness for yourself and forgive others. 11697298161Sbapt** May you share freely, never taking more than you give. 11698298161Sbapt** 11699298161Sbapt****************************************************************************** 11700298161Sbapt** 11701366076Scy** Interfaces to extend FTS5. Using the interfaces defined in this file, 11702298161Sbapt** FTS5 may be extended with: 11703298161Sbapt** 11704298161Sbapt** * custom tokenizers, and 11705298161Sbapt** * custom auxiliary functions. 11706298161Sbapt*/ 11707298161Sbapt 11708298161Sbapt 11709298161Sbapt#ifndef _FTS5_H 11710298161Sbapt#define _FTS5_H 11711298161Sbapt 11712298161Sbapt 11713298161Sbapt#ifdef __cplusplus 11714298161Sbaptextern "C" { 11715298161Sbapt#endif 11716298161Sbapt 11717298161Sbapt/************************************************************************* 11718298161Sbapt** CUSTOM AUXILIARY FUNCTIONS 11719298161Sbapt** 11720298161Sbapt** Virtual table implementations may overload SQL functions by implementing 11721298161Sbapt** the sqlite3_module.xFindFunction() method. 11722298161Sbapt*/ 11723298161Sbapt 11724298161Sbapttypedef struct Fts5ExtensionApi Fts5ExtensionApi; 11725298161Sbapttypedef struct Fts5Context Fts5Context; 11726298161Sbapttypedef struct Fts5PhraseIter Fts5PhraseIter; 11727298161Sbapt 11728298161Sbapttypedef void (*fts5_extension_function)( 11729298161Sbapt const Fts5ExtensionApi *pApi, /* API offered by current FTS version */ 11730298161Sbapt Fts5Context *pFts, /* First arg to pass to pApi functions */ 11731298161Sbapt sqlite3_context *pCtx, /* Context for returning result/error */ 11732298161Sbapt int nVal, /* Number of values in apVal[] array */ 11733298161Sbapt sqlite3_value **apVal /* Array of trailing arguments */ 11734298161Sbapt); 11735298161Sbapt 11736298161Sbaptstruct Fts5PhraseIter { 11737298161Sbapt const unsigned char *a; 11738298161Sbapt const unsigned char *b; 11739298161Sbapt}; 11740298161Sbapt 11741298161Sbapt/* 11742298161Sbapt** EXTENSION API FUNCTIONS 11743298161Sbapt** 11744298161Sbapt** xUserData(pFts): 11745366076Scy** Return a copy of the context pointer the extension function was 11746298161Sbapt** registered with. 11747298161Sbapt** 11748298161Sbapt** xColumnTotalSize(pFts, iCol, pnToken): 11749298161Sbapt** If parameter iCol is less than zero, set output variable *pnToken 11750298161Sbapt** to the total number of tokens in the FTS5 table. Or, if iCol is 11751298161Sbapt** non-negative but less than the number of columns in the table, return 11752366076Scy** the total number of tokens in column iCol, considering all rows in 11753298161Sbapt** the FTS5 table. 11754298161Sbapt** 11755298161Sbapt** If parameter iCol is greater than or equal to the number of columns 11756298161Sbapt** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. 11757366076Scy** an OOM condition or IO error), an appropriate SQLite error code is 11758298161Sbapt** returned. 11759298161Sbapt** 11760298161Sbapt** xColumnCount(pFts): 11761298161Sbapt** Return the number of columns in the table. 11762298161Sbapt** 11763298161Sbapt** xColumnSize(pFts, iCol, pnToken): 11764298161Sbapt** If parameter iCol is less than zero, set output variable *pnToken 11765298161Sbapt** to the total number of tokens in the current row. Or, if iCol is 11766298161Sbapt** non-negative but less than the number of columns in the table, set 11767298161Sbapt** *pnToken to the number of tokens in column iCol of the current row. 11768298161Sbapt** 11769298161Sbapt** If parameter iCol is greater than or equal to the number of columns 11770298161Sbapt** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. 11771366076Scy** an OOM condition or IO error), an appropriate SQLite error code is 11772298161Sbapt** returned. 11773298161Sbapt** 11774298161Sbapt** This function may be quite inefficient if used with an FTS5 table 11775298161Sbapt** created with the "columnsize=0" option. 11776298161Sbapt** 11777298161Sbapt** xColumnText: 11778298161Sbapt** This function attempts to retrieve the text of column iCol of the 11779298161Sbapt** current document. If successful, (*pz) is set to point to a buffer 11780298161Sbapt** containing the text in utf-8 encoding, (*pn) is set to the size in bytes 11781298161Sbapt** (not characters) of the buffer and SQLITE_OK is returned. Otherwise, 11782298161Sbapt** if an error occurs, an SQLite error code is returned and the final values 11783298161Sbapt** of (*pz) and (*pn) are undefined. 11784298161Sbapt** 11785298161Sbapt** xPhraseCount: 11786298161Sbapt** Returns the number of phrases in the current query expression. 11787298161Sbapt** 11788298161Sbapt** xPhraseSize: 11789298161Sbapt** Returns the number of tokens in phrase iPhrase of the query. Phrases 11790298161Sbapt** are numbered starting from zero. 11791298161Sbapt** 11792298161Sbapt** xInstCount: 11793298161Sbapt** Set *pnInst to the total number of occurrences of all phrases within 11794298161Sbapt** the query within the current row. Return SQLITE_OK if successful, or 11795298161Sbapt** an error code (i.e. SQLITE_NOMEM) if an error occurs. 11796298161Sbapt** 11797298161Sbapt** This API can be quite slow if used with an FTS5 table created with the 11798366076Scy** "detail=none" or "detail=column" option. If the FTS5 table is created 11799366076Scy** with either "detail=none" or "detail=column" and "content=" option 11800298161Sbapt** (i.e. if it is a contentless table), then this API always returns 0. 11801298161Sbapt** 11802298161Sbapt** xInst: 11803298161Sbapt** Query for the details of phrase match iIdx within the current row. 11804298161Sbapt** Phrase matches are numbered starting from zero, so the iIdx argument 11805298161Sbapt** should be greater than or equal to zero and smaller than the value 11806298161Sbapt** output by xInstCount(). 11807298161Sbapt** 11808298161Sbapt** Usually, output parameter *piPhrase is set to the phrase number, *piCol 11809298161Sbapt** to the column in which it occurs and *piOff the token offset of the 11810346442Scy** first token of the phrase. Returns SQLITE_OK if successful, or an error 11811346442Scy** code (i.e. SQLITE_NOMEM) if an error occurs. 11812298161Sbapt** 11813298161Sbapt** This API can be quite slow if used with an FTS5 table created with the 11814366076Scy** "detail=none" or "detail=column" option. 11815298161Sbapt** 11816298161Sbapt** xRowid: 11817298161Sbapt** Returns the rowid of the current row. 11818298161Sbapt** 11819298161Sbapt** xTokenize: 11820298161Sbapt** Tokenize text using the tokenizer belonging to the FTS5 table. 11821298161Sbapt** 11822298161Sbapt** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback): 11823298161Sbapt** This API function is used to query the FTS table for phrase iPhrase 11824298161Sbapt** of the current query. Specifically, a query equivalent to: 11825298161Sbapt** 11826298161Sbapt** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid 11827298161Sbapt** 11828298161Sbapt** with $p set to a phrase equivalent to the phrase iPhrase of the 11829305002Scy** current query is executed. Any column filter that applies to 11830366076Scy** phrase iPhrase of the current query is included in $p. For each 11831366076Scy** row visited, the callback function passed as the fourth argument 11832366076Scy** is invoked. The context and API objects passed to the callback 11833305002Scy** function may be used to access the properties of each matched row. 11834366076Scy** Invoking Api.xUserData() returns a copy of the pointer passed as 11835305002Scy** the third argument to pUserData. 11836298161Sbapt** 11837298161Sbapt** If the callback function returns any value other than SQLITE_OK, the 11838298161Sbapt** query is abandoned and the xQueryPhrase function returns immediately. 11839298161Sbapt** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK. 11840298161Sbapt** Otherwise, the error code is propagated upwards. 11841298161Sbapt** 11842298161Sbapt** If the query runs to completion without incident, SQLITE_OK is returned. 11843298161Sbapt** Or, if some error occurs before the query completes or is aborted by 11844298161Sbapt** the callback, an SQLite error code is returned. 11845298161Sbapt** 11846298161Sbapt** 11847298161Sbapt** xSetAuxdata(pFts5, pAux, xDelete) 11848298161Sbapt** 11849366076Scy** Save the pointer passed as the second argument as the extension function's 11850298161Sbapt** "auxiliary data". The pointer may then be retrieved by the current or any 11851298161Sbapt** future invocation of the same fts5 extension function made as part of 11852347347Scy** the same MATCH query using the xGetAuxdata() API. 11853298161Sbapt** 11854298161Sbapt** Each extension function is allocated a single auxiliary data slot for 11855366076Scy** each FTS query (MATCH expression). If the extension function is invoked 11856366076Scy** more than once for a single FTS query, then all invocations share a 11857298161Sbapt** single auxiliary data context. 11858298161Sbapt** 11859298161Sbapt** If there is already an auxiliary data pointer when this function is 11860298161Sbapt** invoked, then it is replaced by the new pointer. If an xDelete callback 11861298161Sbapt** was specified along with the original pointer, it is invoked at this 11862298161Sbapt** point. 11863298161Sbapt** 11864298161Sbapt** The xDelete callback, if one is specified, is also invoked on the 11865298161Sbapt** auxiliary data pointer after the FTS5 query has finished. 11866298161Sbapt** 11867347347Scy** If an error (e.g. an OOM condition) occurs within this function, 11868298161Sbapt** the auxiliary data is set to NULL and an error code returned. If the 11869298161Sbapt** xDelete parameter was not NULL, it is invoked on the auxiliary data 11870298161Sbapt** pointer before returning. 11871298161Sbapt** 11872298161Sbapt** 11873298161Sbapt** xGetAuxdata(pFts5, bClear) 11874298161Sbapt** 11875366076Scy** Returns the current auxiliary data pointer for the fts5 extension 11876298161Sbapt** function. See the xSetAuxdata() method for details. 11877298161Sbapt** 11878298161Sbapt** If the bClear argument is non-zero, then the auxiliary data is cleared 11879298161Sbapt** (set to NULL) before this function returns. In this case the xDelete, 11880298161Sbapt** if any, is not invoked. 11881298161Sbapt** 11882298161Sbapt** 11883298161Sbapt** xRowCount(pFts5, pnRow) 11884298161Sbapt** 11885298161Sbapt** This function is used to retrieve the total number of rows in the table. 11886298161Sbapt** In other words, the same value that would be returned by: 11887298161Sbapt** 11888298161Sbapt** SELECT count(*) FROM ftstable; 11889298161Sbapt** 11890298161Sbapt** xPhraseFirst() 11891298161Sbapt** This function is used, along with type Fts5PhraseIter and the xPhraseNext 11892298161Sbapt** method, to iterate through all instances of a single query phrase within 11893298161Sbapt** the current row. This is the same information as is accessible via the 11894298161Sbapt** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient 11895366076Scy** to use, this API may be faster under some circumstances. To iterate 11896298161Sbapt** through instances of phrase iPhrase, use the following code: 11897298161Sbapt** 11898298161Sbapt** Fts5PhraseIter iter; 11899298161Sbapt** int iCol, iOff; 11900298161Sbapt** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff); 11901298161Sbapt** iCol>=0; 11902298161Sbapt** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff) 11903298161Sbapt** ){ 11904298161Sbapt** // An instance of phrase iPhrase at offset iOff of column iCol 11905298161Sbapt** } 11906298161Sbapt** 11907298161Sbapt** The Fts5PhraseIter structure is defined above. Applications should not 11908298161Sbapt** modify this structure directly - it should only be used as shown above 11909298161Sbapt** with the xPhraseFirst() and xPhraseNext() API methods (and by 11910298161Sbapt** xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below). 11911298161Sbapt** 11912298161Sbapt** This API can be quite slow if used with an FTS5 table created with the 11913366076Scy** "detail=none" or "detail=column" option. If the FTS5 table is created 11914366076Scy** with either "detail=none" or "detail=column" and "content=" option 11915298161Sbapt** (i.e. if it is a contentless table), then this API always iterates 11916298161Sbapt** through an empty set (all calls to xPhraseFirst() set iCol to -1). 11917298161Sbapt** 11918298161Sbapt** xPhraseNext() 11919298161Sbapt** See xPhraseFirst above. 11920298161Sbapt** 11921298161Sbapt** xPhraseFirstColumn() 11922298161Sbapt** This function and xPhraseNextColumn() are similar to the xPhraseFirst() 11923298161Sbapt** and xPhraseNext() APIs described above. The difference is that instead 11924298161Sbapt** of iterating through all instances of a phrase in the current row, these 11925298161Sbapt** APIs are used to iterate through the set of columns in the current row 11926298161Sbapt** that contain one or more instances of a specified phrase. For example: 11927298161Sbapt** 11928298161Sbapt** Fts5PhraseIter iter; 11929298161Sbapt** int iCol; 11930298161Sbapt** for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol); 11931298161Sbapt** iCol>=0; 11932298161Sbapt** pApi->xPhraseNextColumn(pFts, &iter, &iCol) 11933298161Sbapt** ){ 11934298161Sbapt** // Column iCol contains at least one instance of phrase iPhrase 11935298161Sbapt** } 11936298161Sbapt** 11937298161Sbapt** This API can be quite slow if used with an FTS5 table created with the 11938366076Scy** "detail=none" option. If the FTS5 table is created with either 11939366076Scy** "detail=none" "content=" option (i.e. if it is a contentless table), 11940366076Scy** then this API always iterates through an empty set (all calls to 11941298161Sbapt** xPhraseFirstColumn() set iCol to -1). 11942298161Sbapt** 11943298161Sbapt** The information accessed using this API and its companion 11944298161Sbapt** xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext 11945298161Sbapt** (or xInst/xInstCount). The chief advantage of this API is that it is 11946298161Sbapt** significantly more efficient than those alternatives when used with 11947366076Scy** "detail=column" tables. 11948298161Sbapt** 11949298161Sbapt** xPhraseNextColumn() 11950298161Sbapt** See xPhraseFirstColumn above. 11951298161Sbapt*/ 11952298161Sbaptstruct Fts5ExtensionApi { 11953298161Sbapt int iVersion; /* Currently always set to 3 */ 11954298161Sbapt 11955298161Sbapt void *(*xUserData)(Fts5Context*); 11956298161Sbapt 11957298161Sbapt int (*xColumnCount)(Fts5Context*); 11958298161Sbapt int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow); 11959298161Sbapt int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken); 11960298161Sbapt 11961366076Scy int (*xTokenize)(Fts5Context*, 11962298161Sbapt const char *pText, int nText, /* Text to tokenize */ 11963298161Sbapt void *pCtx, /* Context passed to xToken() */ 11964298161Sbapt int (*xToken)(void*, int, const char*, int, int, int) /* Callback */ 11965298161Sbapt ); 11966298161Sbapt 11967298161Sbapt int (*xPhraseCount)(Fts5Context*); 11968298161Sbapt int (*xPhraseSize)(Fts5Context*, int iPhrase); 11969298161Sbapt 11970298161Sbapt int (*xInstCount)(Fts5Context*, int *pnInst); 11971298161Sbapt int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff); 11972298161Sbapt 11973298161Sbapt sqlite3_int64 (*xRowid)(Fts5Context*); 11974298161Sbapt int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn); 11975298161Sbapt int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken); 11976298161Sbapt 11977298161Sbapt int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData, 11978298161Sbapt int(*)(const Fts5ExtensionApi*,Fts5Context*,void*) 11979298161Sbapt ); 11980298161Sbapt int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*)); 11981298161Sbapt void *(*xGetAuxdata)(Fts5Context*, int bClear); 11982298161Sbapt 11983298161Sbapt int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*); 11984298161Sbapt void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff); 11985298161Sbapt 11986298161Sbapt int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*); 11987298161Sbapt void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol); 11988298161Sbapt}; 11989298161Sbapt 11990366076Scy/* 11991298161Sbapt** CUSTOM AUXILIARY FUNCTIONS 11992298161Sbapt*************************************************************************/ 11993298161Sbapt 11994298161Sbapt/************************************************************************* 11995298161Sbapt** CUSTOM TOKENIZERS 11996298161Sbapt** 11997366076Scy** Applications may also register custom tokenizer types. A tokenizer 11998366076Scy** is registered by providing fts5 with a populated instance of the 11999298161Sbapt** following structure. All structure methods must be defined, setting 12000298161Sbapt** any member of the fts5_tokenizer struct to NULL leads to undefined 12001298161Sbapt** behaviour. The structure methods are expected to function as follows: 12002298161Sbapt** 12003298161Sbapt** xCreate: 12004305002Scy** This function is used to allocate and initialize a tokenizer instance. 12005298161Sbapt** A tokenizer instance is required to actually tokenize text. 12006298161Sbapt** 12007298161Sbapt** The first argument passed to this function is a copy of the (void*) 12008298161Sbapt** pointer provided by the application when the fts5_tokenizer object 12009366076Scy** was registered with FTS5 (the third argument to xCreateTokenizer()). 12010298161Sbapt** The second and third arguments are an array of nul-terminated strings 12011298161Sbapt** containing the tokenizer arguments, if any, specified following the 12012298161Sbapt** tokenizer name as part of the CREATE VIRTUAL TABLE statement used 12013298161Sbapt** to create the FTS5 table. 12014298161Sbapt** 12015366076Scy** The final argument is an output variable. If successful, (*ppOut) 12016298161Sbapt** should be set to point to the new tokenizer handle and SQLITE_OK 12017298161Sbapt** returned. If an error occurs, some value other than SQLITE_OK should 12018366076Scy** be returned. In this case, fts5 assumes that the final value of *ppOut 12019298161Sbapt** is undefined. 12020298161Sbapt** 12021298161Sbapt** xDelete: 12022298161Sbapt** This function is invoked to delete a tokenizer handle previously 12023298161Sbapt** allocated using xCreate(). Fts5 guarantees that this function will 12024298161Sbapt** be invoked exactly once for each successful call to xCreate(). 12025298161Sbapt** 12026298161Sbapt** xTokenize: 12027366076Scy** This function is expected to tokenize the nText byte string indicated 12028298161Sbapt** by argument pText. pText may or may not be nul-terminated. The first 12029298161Sbapt** argument passed to this function is a pointer to an Fts5Tokenizer object 12030298161Sbapt** returned by an earlier call to xCreate(). 12031298161Sbapt** 12032298161Sbapt** The second argument indicates the reason that FTS5 is requesting 12033298161Sbapt** tokenization of the supplied text. This is always one of the following 12034298161Sbapt** four values: 12035298161Sbapt** 12036298161Sbapt** <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into 12037298161Sbapt** or removed from the FTS table. The tokenizer is being invoked to 12038298161Sbapt** determine the set of tokens to add to (or delete from) the 12039298161Sbapt** FTS index. 12040298161Sbapt** 12041366076Scy** <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed 12042366076Scy** against the FTS index. The tokenizer is being called to tokenize 12043298161Sbapt** a bareword or quoted string specified as part of the query. 12044298161Sbapt** 12045298161Sbapt** <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as 12046298161Sbapt** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is 12047298161Sbapt** followed by a "*" character, indicating that the last token 12048298161Sbapt** returned by the tokenizer will be treated as a token prefix. 12049298161Sbapt** 12050366076Scy** <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to 12051298161Sbapt** satisfy an fts5_api.xTokenize() request made by an auxiliary 12052298161Sbapt** function. Or an fts5_api.xColumnSize() request made by the same 12053366076Scy** on a columnsize=0 database. 12054298161Sbapt** </ul> 12055298161Sbapt** 12056298161Sbapt** For each token in the input string, the supplied callback xToken() must 12057298161Sbapt** be invoked. The first argument to it should be a copy of the pointer 12058298161Sbapt** passed as the second argument to xTokenize(). The third and fourth 12059298161Sbapt** arguments are a pointer to a buffer containing the token text, and the 12060298161Sbapt** size of the token in bytes. The 4th and 5th arguments are the byte offsets 12061298161Sbapt** of the first byte of and first byte immediately following the text from 12062298161Sbapt** which the token is derived within the input. 12063298161Sbapt** 12064298161Sbapt** The second argument passed to the xToken() callback ("tflags") should 12065366076Scy** normally be set to 0. The exception is if the tokenizer supports 12066298161Sbapt** synonyms. In this case see the discussion below for details. 12067298161Sbapt** 12068366076Scy** FTS5 assumes the xToken() callback is invoked for each token in the 12069298161Sbapt** order that they occur within the input text. 12070298161Sbapt** 12071298161Sbapt** If an xToken() callback returns any value other than SQLITE_OK, then 12072298161Sbapt** the tokenization should be abandoned and the xTokenize() method should 12073298161Sbapt** immediately return a copy of the xToken() return value. Or, if the 12074298161Sbapt** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally, 12075298161Sbapt** if an error occurs with the xTokenize() implementation itself, it 12076298161Sbapt** may abandon the tokenization and return any error code other than 12077298161Sbapt** SQLITE_OK or SQLITE_DONE. 12078298161Sbapt** 12079298161Sbapt** SYNONYM SUPPORT 12080298161Sbapt** 12081298161Sbapt** Custom tokenizers may also support synonyms. Consider a case in which a 12082366076Scy** user wishes to query for a phrase such as "first place". Using the 12083298161Sbapt** built-in tokenizers, the FTS5 query 'first + place' will match instances 12084298161Sbapt** of "first place" within the document set, but not alternative forms 12085298161Sbapt** such as "1st place". In some applications, it would be better to match 12086298161Sbapt** all instances of "first place" or "1st place" regardless of which form 12087298161Sbapt** the user specified in the MATCH query text. 12088298161Sbapt** 12089298161Sbapt** There are several ways to approach this in FTS5: 12090298161Sbapt** 12091361456Scy** <ol><li> By mapping all synonyms to a single token. In this case, using 12092361456Scy** the above example, this means that the tokenizer returns the 12093298161Sbapt** same token for inputs "first" and "1st". Say that token is in 12094298161Sbapt** fact "first", so that when the user inserts the document "I won 12095298161Sbapt** 1st place" entries are added to the index for tokens "i", "won", 12096298161Sbapt** "first" and "place". If the user then queries for '1st + place', 12097298161Sbapt** the tokenizer substitutes "first" for "1st" and the query works 12098298161Sbapt** as expected. 12099298161Sbapt** 12100346442Scy** <li> By querying the index for all synonyms of each query term 12101346442Scy** separately. In this case, when tokenizing query text, the 12102366076Scy** tokenizer may provide multiple synonyms for a single term 12103366076Scy** within the document. FTS5 then queries the index for each 12104346442Scy** synonym individually. For example, faced with the query: 12105298161Sbapt** 12106298161Sbapt** <codeblock> 12107298161Sbapt** ... MATCH 'first place'</codeblock> 12108298161Sbapt** 12109298161Sbapt** the tokenizer offers both "1st" and "first" as synonyms for the 12110366076Scy** first token in the MATCH query and FTS5 effectively runs a query 12111298161Sbapt** similar to: 12112298161Sbapt** 12113298161Sbapt** <codeblock> 12114298161Sbapt** ... MATCH '(first OR 1st) place'</codeblock> 12115298161Sbapt** 12116298161Sbapt** except that, for the purposes of auxiliary functions, the query 12117366076Scy** still appears to contain just two phrases - "(first OR 1st)" 12118298161Sbapt** being treated as a single phrase. 12119298161Sbapt** 12120298161Sbapt** <li> By adding multiple synonyms for a single term to the FTS index. 12121298161Sbapt** Using this method, when tokenizing document text, the tokenizer 12122366076Scy** provides multiple synonyms for each token. So that when a 12123298161Sbapt** document such as "I won first place" is tokenized, entries are 12124298161Sbapt** added to the FTS index for "i", "won", "first", "1st" and 12125298161Sbapt** "place". 12126298161Sbapt** 12127298161Sbapt** This way, even if the tokenizer does not provide synonyms 12128346442Scy** when tokenizing query text (it should not - to do so would be 12129366076Scy** inefficient), it doesn't matter if the user queries for 12130342292Scy** 'first + place' or '1st + place', as there are entries in the 12131298161Sbapt** FTS index corresponding to both forms of the first token. 12132298161Sbapt** </ol> 12133298161Sbapt** 12134298161Sbapt** Whether it is parsing document or query text, any call to xToken that 12135298161Sbapt** specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit 12136298161Sbapt** is considered to supply a synonym for the previous token. For example, 12137298161Sbapt** when parsing the document "I won first place", a tokenizer that supports 12138298161Sbapt** synonyms would call xToken() 5 times, as follows: 12139298161Sbapt** 12140298161Sbapt** <codeblock> 12141298161Sbapt** xToken(pCtx, 0, "i", 1, 0, 1); 12142298161Sbapt** xToken(pCtx, 0, "won", 3, 2, 5); 12143298161Sbapt** xToken(pCtx, 0, "first", 5, 6, 11); 12144298161Sbapt** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11); 12145298161Sbapt** xToken(pCtx, 0, "place", 5, 12, 17); 12146298161Sbapt**</codeblock> 12147298161Sbapt** 12148298161Sbapt** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time 12149298161Sbapt** xToken() is called. Multiple synonyms may be specified for a single token 12150366076Scy** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence. 12151298161Sbapt** There is no limit to the number of synonyms that may be provided for a 12152298161Sbapt** single token. 12153298161Sbapt** 12154366076Scy** In many cases, method (1) above is the best approach. It does not add 12155298161Sbapt** extra data to the FTS index or require FTS5 to query for multiple terms, 12156298161Sbapt** so it is efficient in terms of disk space and query speed. However, it 12157298161Sbapt** does not support prefix queries very well. If, as suggested above, the 12158342292Scy** token "first" is substituted for "1st" by the tokenizer, then the query: 12159298161Sbapt** 12160298161Sbapt** <codeblock> 12161298161Sbapt** ... MATCH '1s*'</codeblock> 12162298161Sbapt** 12163298161Sbapt** will not match documents that contain the token "1st" (as the tokenizer 12164298161Sbapt** will probably not map "1s" to any prefix of "first"). 12165298161Sbapt** 12166366076Scy** For full prefix support, method (3) may be preferred. In this case, 12167298161Sbapt** because the index contains entries for both "first" and "1st", prefix 12168298161Sbapt** queries such as 'fi*' or '1s*' will match correctly. However, because 12169298161Sbapt** extra entries are added to the FTS index, this method uses more space 12170298161Sbapt** within the database. 12171298161Sbapt** 12172298161Sbapt** Method (2) offers a midpoint between (1) and (3). Using this method, 12173366076Scy** a query such as '1s*' will match documents that contain the literal 12174298161Sbapt** token "1st", but not "first" (assuming the tokenizer is not able to 12175298161Sbapt** provide synonyms for prefixes). However, a non-prefix query like '1st' 12176298161Sbapt** will match against "1st" and "first". This method does not require 12177366076Scy** extra disk space, as no extra entries are added to the FTS index. 12178298161Sbapt** On the other hand, it may require more CPU cycles to run MATCH queries, 12179298161Sbapt** as separate queries of the FTS index are required for each synonym. 12180298161Sbapt** 12181298161Sbapt** When using methods (2) or (3), it is important that the tokenizer only 12182298161Sbapt** provide synonyms when tokenizing document text (method (2)) or query 12183298161Sbapt** text (method (3)), not both. Doing so will not cause any errors, but is 12184298161Sbapt** inefficient. 12185298161Sbapt*/ 12186298161Sbapttypedef struct Fts5Tokenizer Fts5Tokenizer; 12187298161Sbapttypedef struct fts5_tokenizer fts5_tokenizer; 12188298161Sbaptstruct fts5_tokenizer { 12189298161Sbapt int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut); 12190298161Sbapt void (*xDelete)(Fts5Tokenizer*); 12191366076Scy int (*xTokenize)(Fts5Tokenizer*, 12192298161Sbapt void *pCtx, 12193298161Sbapt int flags, /* Mask of FTS5_TOKENIZE_* flags */ 12194366076Scy const char *pText, int nText, 12195298161Sbapt int (*xToken)( 12196298161Sbapt void *pCtx, /* Copy of 2nd argument to xTokenize() */ 12197298161Sbapt int tflags, /* Mask of FTS5_TOKEN_* flags */ 12198298161Sbapt const char *pToken, /* Pointer to buffer containing token */ 12199298161Sbapt int nToken, /* Size of token in bytes */ 12200298161Sbapt int iStart, /* Byte offset of token within input text */ 12201298161Sbapt int iEnd /* Byte offset of end of token within input text */ 12202298161Sbapt ) 12203298161Sbapt ); 12204298161Sbapt}; 12205298161Sbapt 12206298161Sbapt/* Flags that may be passed as the third argument to xTokenize() */ 12207298161Sbapt#define FTS5_TOKENIZE_QUERY 0x0001 12208298161Sbapt#define FTS5_TOKENIZE_PREFIX 0x0002 12209298161Sbapt#define FTS5_TOKENIZE_DOCUMENT 0x0004 12210298161Sbapt#define FTS5_TOKENIZE_AUX 0x0008 12211298161Sbapt 12212298161Sbapt/* Flags that may be passed by the tokenizer implementation back to FTS5 12213298161Sbapt** as the third argument to the supplied xToken callback. */ 12214298161Sbapt#define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token */ 12215298161Sbapt 12216298161Sbapt/* 12217298161Sbapt** END OF CUSTOM TOKENIZERS 12218298161Sbapt*************************************************************************/ 12219298161Sbapt 12220298161Sbapt/************************************************************************* 12221298161Sbapt** FTS5 EXTENSION REGISTRATION API 12222298161Sbapt*/ 12223298161Sbapttypedef struct fts5_api fts5_api; 12224298161Sbaptstruct fts5_api { 12225298161Sbapt int iVersion; /* Currently always set to 2 */ 12226298161Sbapt 12227298161Sbapt /* Create a new tokenizer */ 12228298161Sbapt int (*xCreateTokenizer)( 12229298161Sbapt fts5_api *pApi, 12230298161Sbapt const char *zName, 12231298161Sbapt void *pContext, 12232298161Sbapt fts5_tokenizer *pTokenizer, 12233298161Sbapt void (*xDestroy)(void*) 12234298161Sbapt ); 12235298161Sbapt 12236298161Sbapt /* Find an existing tokenizer */ 12237298161Sbapt int (*xFindTokenizer)( 12238298161Sbapt fts5_api *pApi, 12239298161Sbapt const char *zName, 12240298161Sbapt void **ppContext, 12241298161Sbapt fts5_tokenizer *pTokenizer 12242298161Sbapt ); 12243298161Sbapt 12244298161Sbapt /* Create a new auxiliary function */ 12245298161Sbapt int (*xCreateFunction)( 12246298161Sbapt fts5_api *pApi, 12247298161Sbapt const char *zName, 12248298161Sbapt void *pContext, 12249298161Sbapt fts5_extension_function xFunction, 12250298161Sbapt void (*xDestroy)(void*) 12251298161Sbapt ); 12252298161Sbapt}; 12253298161Sbapt 12254298161Sbapt/* 12255298161Sbapt** END OF REGISTRATION API 12256298161Sbapt*************************************************************************/ 12257298161Sbapt 12258298161Sbapt#ifdef __cplusplus 12259298161Sbapt} /* end of the 'extern "C"' block */ 12260298161Sbapt#endif 12261298161Sbapt 12262298161Sbapt#endif /* _FTS5_H */ 12263298161Sbapt 12264305002Scy/******** End of fts5.h *********/ 12265