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<th colspan="3" align="center">DB_TXN->commit()</th>
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<th width="60%" align="center">Chapter 12.
The DB_TXN Handle
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<div class="sect1" lang="en" xml:lang="en">
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<div>
<h2 class="title" style="clear: both"><a id="txncommit"></a>DB_TXN->commit()</h2>
</div>
</div>
</div>
<pre class="programlisting">#include <db.h>
int
DB_TXN->commit(DB_TXN *tid, u_int32_t flags); </pre>
<p>
The <code class="methodname">DB_TXN->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">DB_TXN->commit()</code> has been called, regardless of its return, the
<a class="link" href="txn.html" title="Chapter 12. The DB_TXN Handle">DB_TXN</a> handle may not be
accessed again. If <code class="methodname">DB_TXN->commit()</code> encounters an error, the
transaction and all child transactions of the transaction are aborted.
</p>
<p>
The <code class="methodname">DB_TXN->commit()</code> <span>
<span>
method returns a non-zero error value on failure and 0 on success.
</span>
</span>
</p>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id1709077"></a>Parameters</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1709228"></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="DB_ENV->set_flags()">DB_ENV->set_flags()</a>
method or for a single transaction using the
<a class="xref" href="txnbegin.html" title="DB_ENV->txn_begin()">DB_ENV->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="DB_ENV->set_flags()">DB_ENV->set_flags()</a> method.
This behavior may also be set for a single transaction using the
<a class="xref" href="txnbegin.html" title="DB_ENV->txn_begin()">DB_ENV->txn_begin()</a>
method. Any value specified to this method overrides both of those
settings.
</p>
</li>
</ul>
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<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id1709317"></a>Class</h3>
</div>
</div>
</div>
<p>
<a class="link" href="env.html" title="Chapter 5. The DB_ENV Handle">DB_ENV</a>, <a class="link" href="txn.html" title="Chapter 12. The DB_TXN Handle">DB_TXN</a>
</p>
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<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id1709498"></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>
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