59 lines
4.3 KiB
HTML
59 lines
4.3 KiB
HTML
<?xml version="1.0" encoding="UTF-8"?>
|
|
<!DOCTYPE html
|
|
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
|
|
<html lang="en-us" xml:lang="en-us">
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
|
|
<meta name="security" content="public" />
|
|
<meta name="Robots" content="index,follow" />
|
|
<meta http-equiv="PICS-Label" content='(PICS-1.1 "http://www.icra.org/ratingsv02.html" l gen true r (cz 1 lz 1 nz 1 oz 1 vz 1) "http://www.rsac.org/ratingsv01.html" l gen true r (n 0 s 0 v 0 l 0) "http://www.classify.org/safesurf/" l gen true r (SS~~000 1))' />
|
|
<meta name="DC.Type" content="concept" />
|
|
<meta name="DC.Title" content="Application design tips for database performance" />
|
|
<meta name="abstract" content="There are some design tips that you can apply when designing SQL applications to maximize your database performance." />
|
|
<meta name="description" content="There are some design tips that you can apply when designing SQL applications to maximize your database performance." />
|
|
<meta name="DC.Relation" scheme="URI" content="rzajqkickoff.htm" />
|
|
<meta name="DC.Relation" scheme="URI" content="livedata.htm" />
|
|
<meta name="DC.Relation" scheme="URI" content="reduceopens.htm" />
|
|
<meta name="DC.Relation" scheme="URI" content="retaincursors.htm" />
|
|
<meta name="copyright" content="(C) Copyright IBM Corporation 1998, 2006" />
|
|
<meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 1998, 2006" />
|
|
<meta name="DC.Format" content="XHTML" />
|
|
<meta name="DC.Identifier" content="opens" />
|
|
<meta name="DC.Language" content="en-us" />
|
|
<!-- All rights reserved. Licensed Materials Property of IBM -->
|
|
<!-- US Government Users Restricted Rights -->
|
|
<!-- Use, duplication or disclosure restricted by -->
|
|
<!-- GSA ADP Schedule Contract with IBM Corp. -->
|
|
<link rel="stylesheet" type="text/css" href="./ibmdita.css" />
|
|
<link rel="stylesheet" type="text/css" href="./ic.css" />
|
|
<title>Application design tips for database performance</title>
|
|
</head>
|
|
<body id="opens"><a name="opens"><!-- --></a>
|
|
<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
|
|
<h1 class="topictitle1">Application design tips for database performance</h1>
|
|
<div><p>There are some design tips that you can apply when designing SQL
|
|
applications to maximize your database performance.</p>
|
|
</div>
|
|
<div>
|
|
<ul class="ullinks">
|
|
<li class="ulchildlink"><strong><a href="livedata.htm">Use live data</a></strong><br />
|
|
The term <em>live data</em> refers to the type of access
|
|
that the database manager uses when it retrieves data without making a copy
|
|
of the data. Using this type of access, the data, which is returned to the
|
|
program, always reflects the current values of the data in the database. The
|
|
programmer can control whether the database manager uses a copy of the data
|
|
or retrieves the data directly. This is done by specifying the allow copy
|
|
data (ALWCPYDTA) parameter on the precompiler commands or on the <span class="cmdname">Start
|
|
SQL (STRSQL)</span> command.</li>
|
|
<li class="ulchildlink"><strong><a href="reduceopens.htm">Reduce the number of open operations</a></strong><br />
|
|
The SQL data manipulation language statements must do database open operations in order to create an open data path (ODP) to the data. An open data path is the path through which all input/output operations for the table are performed. In a sense, it connects the SQL application to a table. The number of open operations in a program can significantly affect performance.</li>
|
|
<li class="ulchildlink"><strong><a href="retaincursors.htm">Retain cursor positions</a></strong><br />
|
|
You can improve performance by retaining cursor positions.</li>
|
|
</ul>
|
|
|
|
<div class="familylinks">
|
|
<div class="parentlink"><strong>Parent topic:</strong> <a href="rzajqkickoff.htm" title="The goal of database performance tuning is to minimize the response time of your queries and to make the best use of your server's resources by minimizing network traffic, disk I/O, and CPU time. This goal can only be achieved by understanding the logical and physical structure of your data, understanding the applications used on your server, and understanding how the many conflicting uses of your database may impact database performance.">Performance and query optimization</a></div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html> |