1<!--$Id: dbc_del.so,v 10.49 2007/10/24 16:06:07 bostic Exp $--> 2<!--Copyright (c) 1997,2008 Oracle. All rights reserved.--> 3<!--See the file LICENSE for redistribution information.--> 4<html> 5<head> 6<title>Berkeley DB: Dbc::del</title> 7<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> 8<meta name="keywords" content="embedded,database,programmatic,toolkit,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++"> 9</head> 10<body bgcolor=white> 11<table width="100%"><tr valign=top> 12<td> 13<b>Dbc::del</b> 14</td> 15<td align=right> 16<a href="/api_cxx/api_core.html"><img src="/images/api.gif" alt="API"></a> 17<a href="/ref/toc.html"><img src="/images/ref.gif" alt="Ref"></a></td> 18</tr></table> 19<hr size=1 noshade> 20<tt> 21<b><pre> 22#include <db_cxx.h> 23<p> 24int 25Dbc::del(u_int32_t flags); 26</pre></b> 27<hr size=1 noshade> 28<b>Description: Dbc::del</b> 29<p>The Dbc::del method deletes the key/data pair to which the cursor 30refers.</p> 31<p>When called on a cursor opened on a database that has been made into a 32secondary index using the <a href="/api_cxx/db_associate.html">Db::associate</a> method, the <a href="/api_cxx/db_del.html">Db::del</a> method 33deletes the key/data pair from the primary database and all secondary 34indices.</p> 35<p>The cursor position is unchanged after a delete, and subsequent calls to 36cursor functions expecting the cursor to refer to an existing key will 37fail.</p> 38<p>The Dbc::del method will return <a href="/ref/program/errorret.html#DB_KEYEMPTY">DB_KEYEMPTY</a> if the element has already been deleted. 39Unless otherwise specified, the Dbc::del method 40either returns a non-zero error value 41or throws an exception that encapsulates a non-zero error value on 42failure, and returns 0 on success. 43</p> 44<b>Parameters</b> <br> 45 <b>flags</b><ul compact><li>The <b>flags</b> parameter is currently unused, and must be set to 0.</ul> 46<br> 47<br><b>Errors</b> 48<p>The Dbc::del method 49may fail and throw 50<a href="/api_cxx/except_class.html">DbException</a>, 51encapsulating one of the following non-zero errors, or return one of 52the following non-zero errors:</p> 53<br> 54<b>DB_REP_HANDLE_DEAD</b><ul compact><li>The database handle has been invalidated because a replication election 55unrolled a committed transaction.</ul> 56<br> 57<br> 58<b>DB_REP_LOCKOUT</b><ul compact><li>The operation was blocked by client/master synchronization.</ul> 59<br> 60<br> 61<b>DB_SECONDARY_BAD</b><ul compact><li>A secondary index references a nonexistent primary key.</ul> 62<br> 63<br> 64<b>EACCES</b><ul compact><li>An attempt was made to modify a read-only database.</ul> 65<br> 66<br> 67<b>EINVAL</b><ul compact><li>If the cursor has not been initialized; or if an 68invalid flag value or parameter was specified.</ul> 69<br> 70<br> 71<b>EPERM </b><ul compact><li>Write attempted on read-only cursor when the <a href="/api_cxx/env_open.html#DB_INIT_CDB">DB_INIT_CDB</a> flag was 72specified to <a href="/api_cxx/env_open.html">DbEnv::open</a>.</ul> 73<br> 74<p>If a transactional database environment operation was selected to 75resolve a deadlock, the Dbc::del method will fail and 76either return <a href="/ref/program/errorret.html#DB_LOCK_DEADLOCK">DB_LOCK_DEADLOCK</a> or 77throw a <a href="/api_cxx/deadlock_class.html">DbDeadlockException</a> exception.</p> 78<p>If a Berkeley DB Concurrent Data Store database environment configured for lock timeouts was unable 79to grant a lock in the allowed time, the Dbc::del method will fail and 80either return <a href="/ref/program/errorret.html#DB_LOCK_NOTGRANTED">DB_LOCK_NOTGRANTED</a> or 81throw a <a href="/api_cxx/lockng_class.html">DbLockNotGrantedException</a> exception.</p> 82<hr size=1 noshade> 83<br><b>Class</b> 84<a href="/api_cxx/dbc_class.html">Dbc</a> 85<br><b>See Also</b> 86<a href="/api_cxx/dbc_list.html">Database Cursors and Related Methods</a> 87</tt> 88<table width="100%"><tr><td><br></td><td align=right> 89<a href="/api_cxx/api_core.html"><img src="/images/api.gif" alt="API"></a><a href="/ref/toc.html"><img src="/images/ref.gif" alt="Ref"></a> 90</td></tr></table> 91<p><font size=1>Copyright (c) 1996,2008 Oracle. All rights reserved.</font> 92</body> 93</html> 94
