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6<title>Berkeley DB Reference Guide: Retrieving records</title>
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13<td><b><dl><dt>Berkeley DB Reference Guide:<dd>Access Methods</dl></b></td>
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16<p align=center><b>Retrieving records</b></p>
17<p>The <a href="../../api_c/db_get.html">DB-&gt;get</a> method retrieves records from the database.  In general,
18<a href="../../api_c/db_get.html">DB-&gt;get</a> takes a key and returns the associated data from the
19database.</p>
20<p>There are a few flags that you can set to customize retrieval:</p>
21<br>
22<b><a href="../../api_c/db_get.html#DB_GET_BOTH">DB_GET_BOTH</a></b><ul compact><li>Search for a matching key and data item, that is, only return success
23if both the key and the data items match those stored in the database.</ul>
24<b><a href="../../api_c/dbc_get.html#DB_RMW">DB_RMW</a></b><ul compact><li>Read-modify-write: acquire write locks instead of read locks during
25retrieval. This can enhance performance in threaded applications by
26reducing the chance of deadlock.</ul>
27<b><a href="../../api_c/db_get.html#DB_SET_RECNO">DB_SET_RECNO</a></b><ul compact><li>If the underlying database is a Btree, and was configured so that it
28is possible to search it by logical record number, retrieve a specific
29record.</ul>
30<br>
31<p>If the database has been configured to support duplicate records,
32<a href="../../api_c/db_get.html">DB-&gt;get</a> will always return the first data item in the duplicate
33set.</p>
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