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<title>Berkeley DB: Db.sync</title>
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<h1>Db.sync</h1>
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<h3><pre>
import com.sleepycat.db.*;
<p>
public void sync(int flags)
    throws DbException;
</pre></h3>
<h1>Description</h1>
<p>The Db.sync method flushes any cached information to disk.
<p>If the database is in memory only, the Db.sync method has no effect and
will always succeed.
<p>The <b>flags</b> parameter is currently unused, and must be set to 0.
<p><b>It is important to understand that flushing cached information to disk
only minimizes the window of opportunity for corrupted data.</b> Although
unlikely, it is possible for database corruption to happen if a system
or application crash occurs while writing data to the database.  To
ensure that database corruption never occurs, applications must either:
use transactions and logging with automatic recovery; use logging and
application-specific recovery; or edit a copy of the database, and once
all applications using the database have successfully called
<a href="../api_java/db_close.html">Db.close</a>, atomically replace the original database with the
updated copy.
<p>The Db.sync method throws an exception that encapsulates a non-zero error value on
failure.
<h1>Errors</h1>
<p>The Db.sync method may fail and throw an exception encapsulating a non-zero error for the following conditions:
<p><dl compact>
<p><dt>EINVAL<dd>An invalid flag value or parameter was specified.
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<p>The Db.sync 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 Db.sync 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/db_class.html">Db</a>
<h1>See Also</h1>
<a href="../api_java/db_list.html">Databases and Related Methods</a>
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