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<title>Berkeley DB Reference Guide: Flushing the database cache</title>
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<td><h3><dl><dt>Berkeley DB Reference Guide:<dd>Access Methods</dl></h3></td>
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<h1 align=center>Flushing the database cache</h1>
<p>The <a href="../../api_c/db_sync.html">DB->sync</a> method is the standard interface for flushing all modified
records from the database cache to disk.
<p><b>It is important to understand that flushing cached information
to disk only minimizes the window of opportunity for corrupted data, it
does not eliminate the possibility.</b>
<p>While 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:
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<li>Use transactions and logging with automatic recovery.
<li>Use logging and application-specific recovery.
<li>Edit a copy of the database, and, once all applications
using the database have successfully called <a href="../../api_c/db_close.html">DB->close</a>, use
system operations (for example, the POSIX rename system call) to
atomically replace the original database with the updated copy.
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