1<!--$Id: utility.so,v 10.18 2004/10/05 16:44:33 bostic Exp $--> 2<!--Copyright (c) 1997,2008 Oracle. All rights reserved.--> 3<!--See the file LICENSE for redistribution information.--> 4<html> 5<head> 6<title>Berkeley DB Reference Guide: The db_dump and db_load utilities</title> 7<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> 8<meta name="keywords" content="embedded,database,programmatic,toolkit,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++"> 9</head> 10<body bgcolor=white> 11<a name="2"><!--meow--></a> 12<table width="100%"><tr valign=top> 13<td><b><dl><dt>Berkeley DB Reference Guide:<dd>Dumping and Reloading</dl></b></td> 14<td align=right><a href="../ext/php.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../dumpload/format.html"><img src="../../images/next.gif" alt="Next"></a> 15</td></tr></table> 16<p align=center><b>The db_dump and db_load utilities</b></p> 17<p>There are three utilities used for dumping and loading Berkeley DB 18databases: <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> 19<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 20databases into a flat-text representation of the data that can be read 21by <a href="../../utility/db_load.html">db_load</a>. The only difference between them is that 22<a href="../../utility/db_dump.html">db_dump</a> reads Berkeley DB version 2 and greater database formats, 23whereas <a href="../../utility/db_dump.html">db_dump185</a> reads Berkeley DB version 1.85 and 1.86 database 24formats.</p> 25<p>The <a href="../../utility/db_load.html">db_load</a> utility reads either the output format used 26by the dump utilities or (optionally) a flat-text representation 27created using other tools, and stores it into a Berkeley DB database.</p> 28<p>Dumping and reloading Hash databases that use user-defined hash functions 29will result in new databases that use the default hash function. Although 30using the default hash function may not be optimal for the new database, 31it will continue to work correctly.</p> 32<p>Dumping and reloading Btree databases that use user-defined prefix or 33comparison functions will result in new databases that use the default 34prefix and comparison functions. In this case, it is quite likely that 35applications will be unable to retrieve records, and it is possible that 36the load process itself will fail.</p> 37<p>The only available workaround for either Hash or Btree databases is to 38modify the sources for the <a href="../../utility/db_load.html">db_load</a> utility to load the database 39using the correct hash, prefix, and comparison functions.</p> 40<table width="100%"><tr><td><br></td><td align=right><a href="../ext/php.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../dumpload/format.html"><img src="../../images/next.gif" alt="Next"></a> 41</td></tr></table> 42<p><font size=1>Copyright (c) 1996,2008 Oracle. All rights reserved.</font> 43</body> 44</html> 45