1<?xml version="1.0" encoding="UTF-8" standalone="no"?> 2<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 3<html xmlns="http://www.w3.org/1999/xhtml"> 4 <head> 5 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> 6 <title>DbEnv::dbremove()</title> 7 <link rel="stylesheet" href="apiReference.css" type="text/css" /> 8 <meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /> 9 <link rel="start" href="index.html" title="Berkeley DB C++ API Reference" /> 10 <link rel="up" href="env.html" title="Chapter 5. The DbEnv Handle" /> 11 <link rel="prev" href="envcreate.html" title="DbEnv" /> 12 <link rel="next" href="envdbrename.html" title="DbEnv::dbrename()" /> 13 </head> 14 <body> 15 <div class="navheader"> 16 <table width="100%" summary="Navigation header"> 17 <tr> 18 <th colspan="3" align="center">DbEnv::dbremove()</th> 19 </tr> 20 <tr> 21 <td width="20%" align="left"><a accesskey="p" href="envcreate.html">Prev</a> </td> 22 <th width="60%" align="center">Chapter 5. 23 The DbEnv Handle 24 </th> 25 <td width="20%" align="right"> <a accesskey="n" href="envdbrename.html">Next</a></td> 26 </tr> 27 </table> 28 <hr /> 29 </div> 30 <div class="sect1" lang="en" xml:lang="en"> 31 <div class="titlepage"> 32 <div> 33 <div> 34 <h2 class="title" style="clear: both"><a id="envdbremove"></a>DbEnv::dbremove()</h2> 35 </div> 36 </div> 37 </div> 38 <pre class="programlisting">#include <db_cxx.h> 39 40int 41DbEnv::dbremove(DbTxn *txnid, 42 const char *file, const char *database, u_int32_t flags);</pre> 43 <p> 44 The <code class="methodname">DbEnv::dbremove()</code> method removes the database specified by the 45 <span class="bold"><strong>file</strong></span> and <span class="bold"><strong>database</strong></span> parameters. If no <span class="bold"><strong>database</strong></span> is specified, the underlying file 46 represented by <span class="bold"><strong>file</strong></span> is removed, 47 incidentally removing all of the databases it contained. 48 </p> 49 <p> 50 Applications should never remove databases with open 51 <a class="link" href="db.html" title="Chapter 2. The Db Handle">Db</a> handles, or in the case of 52 removing a file, when any database in the file has an open handle. 53 </p> 54 <p> 55 The <code class="methodname">DbEnv::dbremove()</code> <span> 56 57 <span> 58 method either returns a non-zero error value or throws an 59 exception that encapsulates a non-zero error value on 60 failure, and returns 0 on success. 61 </span> 62 </span> 63 </p> 64 <p> 65 <code class="methodname">DbEnv::dbremove()</code> is affected by any database directory specified using the 66 <a class="xref" href="envset_data_dir.html" title="DbEnv::set_data_dir()">DbEnv::set_data_dir()</a> 67 method, or by setting the <code class="literal">set_data_dir</code> string in the environment's 68 <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file. 69 </p> 70 <div class="sect2" lang="en" xml:lang="en"> 71 <div class="titlepage"> 72 <div> 73 <div> 74 <h3 class="title"><a id="id1663248"></a>Parameters</h3> 75 </div> 76 </div> 77 </div> 78 <div class="sect3" lang="en" xml:lang="en"> 79 <div class="titlepage"> 80 <div> 81 <div> 82 <h4 class="title"><a id="id1663259"></a>database</h4> 83 </div> 84 </div> 85 </div> 86 <p> 87 The <span class="bold"><strong>database</strong></span> parameter is the 88 database to be removed. 89 </p> 90 </div> 91 <div class="sect3" lang="en" xml:lang="en"> 92 <div class="titlepage"> 93 <div> 94 <div> 95 <h4 class="title"><a id="id1663497"></a>file</h4> 96 </div> 97 </div> 98 </div> 99 <p> 100 The <span class="bold"><strong>file</strong></span> parameter is the physical 101 file which contains the database(s) to be removed. 102 </p> 103 </div> 104 <div class="sect3" lang="en" xml:lang="en"> 105 <div class="titlepage"> 106 <div> 107 <div> 108 <h4 class="title"><a id="id1663483"></a>txnid</h4> 109 </div> 110 </div> 111 </div> 112 <p> 113 If the operation is part of an application-specified transaction, the 114 <span class="bold"><strong>txnid</strong></span> parameter is a transaction 115 handle returned from 116 <a class="xref" href="txnbegin.html" title="DbEnv::txn_begin()">DbEnv::txn_begin()</a>; if the 117 operation is part of a Berkeley DB Concurrent Data Store group, the 118 <span class="bold"><strong>txnid</strong></span> parameter is a handle returned 119 from <a class="xref" href="envcdsgroup_begin.html" title="DbEnv::cdsgroup_begin()">DbEnv::cdsgroup_begin()</a>; 120 otherwise NULL. If no transaction handle is specified, but the 121 <code class="literal">DB_AUTO_COMMIT</code> flag is specified to either this method 122 or the environment handle, the operation will be implicitly transaction protected. 123 </p> 124 </div> 125 <div class="sect3" lang="en" xml:lang="en"> 126 <div class="titlepage"> 127 <div> 128 <div> 129 <h4 class="title"><a id="id1663412"></a>flags</h4> 130 </div> 131 </div> 132 </div> 133 <p> 134 The <span class="bold"><strong>flags</strong></span> parameter must 135 be set to 0 or the following value: 136 </p> 137 <div class="itemizedlist"> 138 <ul type="disc"> 139 <li> 140 <p> 141 <code class="literal">DB_AUTO_COMMIT</code> 142 </p> 143 <p> 144 Enclose the <code class="classname">DbEnv::dbremove()</code> 145 call within a transaction. If the call succeeds, 146 changes made by the operation will be recoverable. 147 If the call fails, the operation will have made no 148 changes. 149 </p> 150 </li> 151 </ul> 152 </div> 153 </div> 154 </div> 155 <div class="sect2" lang="en" xml:lang="en"> 156 <div class="titlepage"> 157 <div> 158 <div> 159 <h3 class="title"><a id="id1663249"></a>Environment Variables</h3> 160 </div> 161 </div> 162 </div> 163 <p> 164 The environment variable <code class="literal">DB_HOME</code> may be used as the path of 165 the database environment home. 166 </p> 167 </div> 168 <div class="sect2" lang="en" xml:lang="en"> 169 <div class="titlepage"> 170 <div> 171 <div> 172 <h3 class="title"><a id="id1663562"></a>Errors</h3> 173 </div> 174 </div> 175 </div> 176 <p> 177 The <code class="methodname">DbEnv::dbremove()</code> <span> 178 179 <span> 180 method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a> 181 exception, encapsulating one of the following non-zero errors, or return one 182 of the following non-zero errors: 183 </span> 184 </span> 185 </p> 186 <div class="sect3" lang="en" xml:lang="en"> 187 <div class="titlepage"> 188 <div> 189 <div> 190 <h4 class="title"><a id="id1663636"></a><span>DbDeadlockException or </span>DB_LOCK_DEADLOCK</h4> 191 </div> 192 </div> 193 </div> 194 <p> 195 A transactional database environment operation was selected to resolve 196 a deadlock. 197 </p> 198 <p> 199 <a class="xref" href="dbdeadlock.html" title="DbDeadlockException">DbDeadlockException</a> is thrown if 200 your Berkeley DB API is configured to throw exceptions. 201 Otherwise, <code class="literal">DB_LOCK_DEADLOCK</code> is returned. 202 </p> 203 </div> 204 <div class="sect3" lang="en" xml:lang="en"> 205 <div class="titlepage"> 206 <div> 207 <div> 208 <h4 class="title"><a id="id1663446"></a><span>DbLockNotGrantedException or </span>DB_LOCK_NOTGRANTED</h4> 209 </div> 210 </div> 211 </div> 212 <p> 213 A Berkeley DB Concurrent Data Store database environment configured 214 for lock timeouts was unable to grant a lock in the allowed time. 215 </p> 216 <p> 217 <a class="xref" href="dblocknotgranted.html" title="DbLockNotGrantedException">DbLockNotGrantedException</a> is thrown if 218 your Berkeley DB API is configured to throw exceptions. 219 Otherwise, <code class="literal">DB_LOCK_NOTGRANTED</code> is returned. 220 </p> 221 </div> 222 <div class="sect3" lang="en" xml:lang="en"> 223 <div class="titlepage"> 224 <div> 225 <div> 226 <h4 class="title"><a id="id1663425"></a>EINVAL</h4> 227 </div> 228 </div> 229 </div> 230 <p> 231 If the method was called before <a class="xref" href="envopen.html" title="DbEnv::open()">DbEnv::open()</a> 232 was called; or if an invalid flag value or parameter was specified. 233 </p> 234 </div> 235 <div class="sect3" lang="en" xml:lang="en"> 236 <div class="titlepage"> 237 <div> 238 <div> 239 <h4 class="title"><a id="id1663431"></a>ENOENT</h4> 240 </div> 241 </div> 242 </div> 243 <p> 244 The file or directory does not exist. 245 </p> 246 </div> 247 </div> 248 <div class="sect2" lang="en" xml:lang="en"> 249 <div class="titlepage"> 250 <div> 251 <div> 252 <h3 class="title"><a id="id1663642"></a>Class</h3> 253 </div> 254 </div> 255 </div> 256 <p> 257 <a class="link" href="env.html" title="Chapter 5. The DbEnv Handle">DbEnv</a> 258 </p> 259 </div> 260 <div class="sect2" lang="en" xml:lang="en"> 261 <div class="titlepage"> 262 <div> 263 <div> 264 <h3 class="title"><a id="id1663577"></a>See Also</h3> 265 </div> 266 </div> 267 </div> 268 <p> 269 <a class="xref" href="env.html#envlist" title="Database Environments and Related Methods">Database Environments and Related Methods</a> 270 </p> 271 </div> 272 </div> 273 <div class="navfooter"> 274 <hr /> 275 <table width="100%" summary="Navigation footer"> 276 <tr> 277 <td width="40%" align="left"><a accesskey="p" href="envcreate.html">Prev</a> </td> 278 <td width="20%" align="center"> 279 <a accesskey="u" href="env.html">Up</a> 280 </td> 281 <td width="40%" align="right"> <a accesskey="n" href="envdbrename.html">Next</a></td> 282 </tr> 283 <tr> 284 <td width="40%" align="left" valign="top">DbEnv </td> 285 <td width="20%" align="center"> 286 <a accesskey="h" href="index.html">Home</a> 287 </td> 288 <td width="40%" align="right" valign="top"> DbEnv::dbrename()</td> 289 </tr> 290 </table> 291 </div> 292 </body> 293</html> 294