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diff --git a/bdb/docs/ref/upgrade.2.0/convert.html b/bdb/docs/ref/upgrade.2.0/convert.html deleted file mode 100644 index ad5685368dc..00000000000 --- a/bdb/docs/ref/upgrade.2.0/convert.html +++ /dev/null @@ -1,74 +0,0 @@ -<!--$Id: convert.so,v 11.6 2000/03/18 21:43:19 bostic Exp $--> -<!--Copyright 1997, 1998, 1999, 2000 by Sleepycat Software, Inc.--> -<!--All rights reserved.--> -<html> -<head> -<title>Berkeley DB Reference Guide: Release 2.0: converting applications</title> -<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> -<meta name="keywords" content="embedded,database,programmatic,toolkit,b+tree,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,java,C,C++"> -</head> -<body bgcolor=white> -<table><tr valign=top> -<td><h3><dl><dt>Berkeley DB Reference Guide:<dd>Upgrading Berkeley DB Applications</dl></h3></td> -<td width="1%"><a href="../../ref/upgrade.2.0/system.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../../ref/toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../../ref/upgrade.2.0/disk.html"><img src="../../images/next.gif" alt="Next"></a> -</td></tr></table> -<p> -<h1 align=center>Release 2.0: converting applications</h1> -<p>Mapping the Berkeley DB 1.85 functionality into Berkeley DB version 2 is almost always -simple. The manual page <a href="../../api_c/db_open.html">DB->open</a> replaces the Berkeley DB 1.85 manual -pages <b>dbopen</b>(3), <b>btree</b>(3), <b>hash</b>(3) and -<b>recno</b>(3). You should be able to convert each 1.85 function -call into a Berkeley DB version 2 function call using just the <a href="../../api_c/db_open.html">DB->open</a> -documentation. -<p>Some guidelines and things to watch out for: -<p><ol> -<p><li>Most access method functions have exactly the same semantics as in Berkeley DB -1.85, although the arguments to the functions have changed in some cases. -To get your code to compile, the most common change is to add the -transaction ID as an argument (NULL, since Berkeley DB 1.85 did not support -transactions.) -<p><li>You must always initialize DBT structures to zero before using them with -any Berkeley DB version 2 function. (They do not normally have to be -reinitialized each time, only when they are first allocated. Do this by -declaring the DBT structure external or static, or by calling the C -library routine <b>bzero</b>(3) or <b>memset</b>(3).) -<p><li>The error returns are completely different in the two versions. In Berkeley DB -1.85, < 0 meant an error, and > 0 meant a minor Berkeley DB exception. -In Berkeley DB 2.0, > 0 means an error (the Berkeley DB version 2 functions -return <b>errno</b> on error) and < 0 means a Berkeley DB exception. -See <a href="../../ref/program/errorret.html">Error Returns to Applications</a> -for more information. -<p><li>The Berkeley DB 1.85 DB->seq function has been replaced by cursors in Berkeley DB -version 2. The semantics are approximately the same, but cursors require -the creation of an extra object (the DBC object), which is then used to -access the database. -<p>Specifically, the partial key match and range search functionality of the -R_CURSOR flag in DB->seq has been replaced by the -<a href="../../api_c/dbc_get.html#DB_SET_RANGE">DB_SET_RANGE</a> flag in <a href="../../api_c/dbc_get.html">DBcursor->c_get</a>. -<p><li>In version 2 of the Berkeley DB library, additions or deletions into Recno -(fixed and variable-length record) databases no longer automatically -logically renumber all records after the add/delete point, by default. -The default behavior is that deleting records does not cause subsequent -records to be renumbered, and it is an error to attempt to add new records -between records already in the database. Applications wanting the -historic Recno access method semantics should call the -<a href="../../api_c/db_set_flags.html">DB->set_flags</a> function with the <a href="../../api_c/db_set_flags.html#DB_RENUMBER">DB_RENUMBER</a> flag. -<p><li>Opening a database in Berkeley DB version 2 is a much heavier-weight operation -than it was in Berkeley DB 1.85. Therefore, if your historic applications were -written to open a database, perform a single operation, and close the -database, you may observe performance degradation. In most cases, this -is due to the expense of creating the environment upon each open. While -we encourage restructuring your application to avoid repeated opens and -closes, you can probably recover most of the lost performance by simply -using a persistent environment across invocations. -</ol> -<p>While simply converting Berkeley DB 1.85 function calls to Berkeley DB version 2 -function calls will work, we recommend that you eventually reconsider your -application's interface to the Berkeley DB database library in light of the -additional functionality supplied by Berkeley DB version 2, as it is likely to -result in enhanced application performance. -<table><tr><td><br></td><td width="1%"><a href="../../ref/upgrade.2.0/system.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../../ref/toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../../ref/upgrade.2.0/disk.html"><img src="../../images/next.gif" alt="Next"></a> -</td></tr></table> -<p><font size=1><a href="http://www.sleepycat.com">Copyright Sleepycat Software</a></font> -</body> -</html> |