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<title>Berkeley DB Reference Guide: The db_dump and db_load utilities</title>
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<td><b><dl><dt>Berkeley DB Reference Guide:<dd>Dumping and Reloading</dl></b></td>
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<p align=center><b>The db_dump and db_load utilities</b></p>
<p>There are three utilities used for dumping and loading Berkeley DB
databases: <a href="../../utility/db_dump.html">db_dump</a>, <a href="../../utility/db_dump.html">db_dump185</a>, and <a href="../../utility/db_load.html">db_load</a>.</p>
<p>The <a href="../../utility/db_dump.html">db_dump</a> and <a href="../../utility/db_dump.html">db_dump185</a> utilities dump Berkeley DB
databases into a flat-text representation of the data that can be read
by <a href="../../utility/db_load.html">db_load</a>.  The only difference between them is that
<a href="../../utility/db_dump.html">db_dump</a> reads Berkeley DB version 2 and greater database formats,
whereas <a href="../../utility/db_dump.html">db_dump185</a> reads Berkeley DB version 1.85 and 1.86 database
formats.</p>
<p>The <a href="../../utility/db_load.html">db_load</a> utility reads either the output format used
by the dump utilities or (optionally) a flat-text representation
created using other tools, and stores it into a Berkeley DB database.</p>
<p>Dumping and reloading Hash databases that use user-defined hash functions
will result in new databases that use the default hash function. Although
using the default hash function may not be optimal for the new database,
it will continue to work correctly.</p>
<p>Dumping and reloading Btree databases that use user-defined prefix or
comparison functions will result in new databases that use the default
prefix and comparison functions. In this case, it is quite likely that
applications will be unable to retrieve records, and it is possible that
the load process itself will fail.</p>
<p>The only available workaround for either Hash or Btree databases is to
modify the sources for the <a href="../../utility/db_load.html">db_load</a> utility to load the database
using the correct hash, prefix, and comparison functions.</p>
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