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<?xml version="1.0" encoding="UTF-8" standalone="no"?>
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<title>Deleting Secondary Database Records</title>
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<th colspan="3" align="center">Deleting Secondary Database Records</th>
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<th width="60%" align="center">Chapter 10. Secondary Databases</th>
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<h2 class="title" style="clear: both"><a id="secondaryDelete"></a>Deleting Secondary Database Records</h2>
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<p>
In general, you
<span>will</span>
not modify a secondary database directly. In
order to modify a secondary database, you should modify the primary
database and simply allow DB to manage the secondary modifications for you.
</p>
<p>
However, as a convenience, you can delete
<code class="classname">SecondaryDatabase</code>
records directly. Doing so causes the associated primary key/data pair to be deleted.
This in turn causes DB to delete all
<code class="classname">SecondaryDatabase</code>
records that reference the primary record.
</p>
<p>
You can use the
<code class="methodname">SecondaryDatabase.delete()</code>
method to delete a secondary database record. Note that if your
<code class="classname">SecondaryDatabase</code>
contains duplicate records, then deleting a record from the set of
duplicates causes all of the duplicates to be deleted as well.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
<span><code class="methodname">SecondaryDatabase.delete()</code> causes the
previously described delete operations to occur
</span>
only if the primary database is opened for write access.
</p>
</div>
<p>For example:</p>
<a id="java_index7"></a>
<pre class="programlisting">package db.GettingStarted;
import com.sleepycat.db.DatabaseEntry;
import com.sleepycat.db.DatabaseException;
import com.sleepycat.db.OperationStatus;
import com.sleepycat.db.SecondaryDatabase;
...
try {
SecondaryDatabase mySecondaryDatabase = null;
// Omitting all database opens
...
String searchName = "John Doe";
DatabaseEntry searchKey =
new DatabaseEntry(searchName.getBytes("UTF-8"));
// Delete the first secondary record that uses "John Doe" as
// a key. This causes the primary record referenced by this secondary
// record to be deleted.
OperationStatus retVal = mySecondaryDatabase.delete(null, searchKey);
} catch (Exception e) {
// Exception handling goes here
}</pre>
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