<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>DbTxn::commit()</title> <link rel="stylesheet" href="apiReference.css" type="text/css" /> <meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /> <link rel="start" href="index.html" title="Berkeley DB C++ API Reference" /> <link rel="up" href="txn.html" title="Chapter 13. The DbTxn Handle" /> <link rel="prev" href="txncheckpoint.html" title="DbEnv::txn_checkpoint()" /> <link rel="next" href="txndiscard.html" title="DbTxn::discard()" /> </head> <body> <div class="navheader"> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">DbTxn::commit()</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="txncheckpoint.html">Prev</a> </td> <th width="60%" align="center">Chapter 13. The DbTxn Handle </th> <td width="20%" align="right"> <a accesskey="n" href="txndiscard.html">Next</a></td> </tr> </table> <hr /> </div> <div class="sect1" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h2 class="title" style="clear: both"><a id="txncommit"></a>DbTxn::commit()</h2> </div> </div> </div> <pre class="programlisting">#include <db_cxx.h> int DbTxn::commit(u_int32_t flags);</pre> <p> The <code class="methodname">DbTxn::commit()</code> method ends the transaction. </p> <p> In the case of nested transactions, if the transaction is a parent transaction, committing the parent transaction causes all unresolved children of the parent to be committed. In the case of nested transactions, if the transaction is a child transaction, its locks are not released, but are acquired by its parent. Although the commit of the child transaction will succeed, the actual resolution of the child transaction is postponed until the parent transaction is committed or aborted; that is, if its parent transaction commits, it will be committed; and if its parent transaction aborts, it will be aborted. </p> <p> All cursors opened within the transaction must be closed before the transaction is committed. </p> <p> After <code class="methodname">DbTxn::commit()</code> has been called, regardless of its return, the <a class="link" href="txn.html" title="Chapter 13. The DbTxn Handle">DbTxn</a> handle may not be accessed again. If <code class="methodname">DbTxn::commit()</code> encounters an error, the transaction and all child transactions of the transaction are aborted. </p> <p> The <code class="methodname">DbTxn::commit()</code> <span> <span> method either returns a non-zero error value or throws an exception that encapsulates a non-zero error value on failure, and returns 0 on success. </span> </span> </p> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="id1713826"></a>Parameters</h3> </div> </div> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="id1714644"></a>flags</h4> </div> </div> </div> <p> The <span class="bold"><strong>flags</strong></span> parameter must be set to 0 or one of the following values: </p> <div class="itemizedlist"> <ul type="disc"> <li> <p> <code class="literal">DB_TXN_NOSYNC</code> </p> <p> Do not synchronously flush the log. This means the transaction will exhibit the ACI (atomicity, consistency, and isolation) properties, but not D (durability); that is, database integrity will be maintained, but it is possible that this transaction may be undone during recovery. </p> <p> This behavior may be set for a Berkeley DB environment using the <a class="xref" href="envset_flags.html" title="DbEnv::set_flags()">DbEnv::set_flags()</a> method or for a single transaction using the <a class="xref" href="txnbegin.html" title="DbEnv::txn_begin()">DbEnv::txn_begin()</a> method. Any value specified to this method overrides both of those settings. </p> </li> <li> <p> <code class="literal">DB_TXN_SYNC</code> </p> <p> Synchronously flush the log. This means the transaction will exhibit all of the ACID (atomicity, consistency, isolation, and durability) properties. </p> <p> This behavior is the default for Berkeley DB environments unless the <a class="link" href="envset_flags.html#envset_flags_DB_TXN_NOSYNC">DB_TXN_NOSYNC</a> flag was specified to the <a class="xref" href="envset_flags.html" title="DbEnv::set_flags()">DbEnv::set_flags()</a> method. This behavior may also be set for a single transaction using the <a class="xref" href="txnbegin.html" title="DbEnv::txn_begin()">DbEnv::txn_begin()</a> method. Any value specified to this method overrides both of those settings. </p> </li> </ul> </div> </div> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="id1713827"></a>Class</h3> </div> </div> </div> <p> <a class="link" href="env.html" title="Chapter 5. The DbEnv Handle">DbEnv</a>, <a class="link" href="txn.html" title="Chapter 13. The DbTxn Handle">DbTxn</a> </p> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="id1714877"></a>See Also</h3> </div> </div> </div> <p> <a class="xref" href="txn.html#txnlist" title="Transaction Subsystem and Related Methods">Transaction Subsystem and Related Methods</a> </p> </div> </div> <div class="navfooter"> <hr /> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"><a accesskey="p" href="txncheckpoint.html">Prev</a> </td> <td width="20%" align="center"> <a accesskey="u" href="txn.html">Up</a> </td> <td width="40%" align="right"> <a accesskey="n" href="txndiscard.html">Next</a></td> </tr> <tr> <td width="40%" align="left" valign="top">DbEnv::txn_checkpoint() </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> <td width="40%" align="right" valign="top"> DbTxn::discard()</td> </tr> </table> </div> </body> </html>