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<th colspan="3" align="center">Database close</th>
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<th width="60%" align="center">Chapter 3. Access Method Operations </th>
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<h2 class="title" style="clear: both"><a id="am_close"></a>Database close</h2>
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<p>
The <a href="../api_reference/C/dbclose.html" class="olink">DB->close()</a> database handle closes the <a href="../api_reference/C/db.html" class="olink">DB</a> handle. By
default, <a href="../api_reference/C/dbclose.html" class="olink">DB->close()</a> also flushes all modified records from the
database cache to disk.
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<p>
There is one flag that you can set to customize
<a href="../api_reference/C/dbclose.html" class="olink">DB->close()</a>:
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<span class="term">
<a href="../api_reference/C/dbclose.html#dbclose_DB_NOSYNC" class="olink">DB_NOSYNC</a>
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Do not flush cached information to
disk.
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<strong>
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.
</strong>
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<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.
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<li>
Use logging and application-specific
recovery.
</li>
<li>
Edit a copy of the database, and, once all
applications using the database have successfully called
<a href="../api_reference/C/dbclose.html" class="olink">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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