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<title>Berkeley DB Reference Guide: Retrieving records</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>Retrieving records</h1>
<p>The <a href="../../api_c/db_get.html">DB->get</a> function is the standard interface for retrieving records from
the database. In general, <a href="../../api_c/db_get.html">DB->get</a> takes a key and returns the
associated data from the database.
<p>There are a few flags that you can set to customize retrieval:
<p><dl compact>
<p><dt><a href="../../api_c/db_get.html#DB_GET_BOTH">DB_GET_BOTH</a><dd>Search for a matching key and data item, i.e., only return success if both
the key and the data items match those stored in the database.
<p><dt><a href="../../api_c/dbc_get.html#DB_RMW">DB_RMW</a><dd>Read-modify-write: acquire write locks instead of read locks during
retrieval. This can enhance performance in threaded applications by
reducing the chance of deadlock.
<p><dt><a href="../../api_c/db_get.html#DB_SET_RECNO">DB_SET_RECNO</a><dd>If the underlying database is a Btree, and was configured so that it
is possible to search it by logical record number, retrieve a specific
record.
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<p>If the database has been configured to support duplicate records,
<a href="../../api_c/db_get.html">DB->get</a> will always return the first data item in the duplicate
set.
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