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<title>Berkeley DB: DbTxn.commit</title>
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<h1>DbTxn.commit</h1>
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<h3><pre>
import com.sleepycat.db.*;
<p>
public void commit(int flags)
    throws DbException;
</pre></h3>
<h1>Description</h1>
<p>The DbTxn.commit method ends the transaction.
<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>The <b>flags</b> value must be set to 0 or
one of the following values:
<p><dl compact>
<p><dt><a name="Db.DB_TXN_NOSYNC">Db.DB_TXN_NOSYNC</a><dd>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>This behavior may be set for a Berkeley DB environment using the
<a href="../api_java/env_set_flags.html">DbEnv.set_flags</a> interface or for a single transaction using the
<a href="../api_java/txn_begin.html">DbEnv.txn_begin</a> interface.  Any value specified in this interface
overrides both of those settings.
<p><dt><a name="Db.DB_TXN_SYNC">Db.DB_TXN_SYNC</a><dd>Synchronously flush the log.  This means the transaction will exhibit
all of the ACID (atomicity, consistency, isolation, and durability)
properties.
<p>This behavior is the default for Berkeley DB environments unless the
<a href="../api_java/env_set_flags.html#DB_TXN_NOSYNC">Db.DB_TXN_NOSYNC</a> flag was specified to the <a href="../api_java/env_set_flags.html">DbEnv.set_flags</a>
interface.  This behavior may also be set for a single transaction using
the <a href="../api_java/txn_begin.html">DbEnv.txn_begin</a> interface.  Any value specified in this interface
overrides both of those settings.
</dl>
<p>All cursors opened within the transaction must be closed before the
transaction is committed.
<p>After DbTxn.commit has been called, regardless of its return, the
<a href="../api_java/txn_class.html">DbTxn</a> handle may not be accessed again.  If DbTxn.commit
encounters an error, the transaction and all child transactions of the
transaction are aborted.
<p>The DbTxn.commit method throws an exception that encapsulates a non-zero error value on
failure.
<h1>Errors</h1>
<p>The DbTxn.commit method may fail and throw an exception for errors specified for other Berkeley DB and C library or system methods.
If a catastrophic error has occurred, the DbTxn.commit method may fail and
throw a <a href="../api_java/runrec_class.html">DbRunRecoveryException</a>,
in which case all subsequent Berkeley DB calls will fail in the same way.
<h1>Class</h1>
<a href="../api_java/env_class.html">DbEnv</a>, <a href="../api_java/txn_class.html">DbTxn</a>
<h1>See Also</h1>
<a href="../api_java/txn_list.html">Transaction Subsystem and Related Methods</a>
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