53 lines
3.5 KiB
HTML
53 lines
3.5 KiB
HTML
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<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE html
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PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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<html lang="en-us" xml:lang="en-us">
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
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<meta name="security" content="public" />
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<meta name="Robots" content="index,follow" />
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<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))' />
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<meta name="DC.Type" content="concept" />
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<meta name="DC.Title" content="Queries using Classic Query Engine" />
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<meta name="abstract" content="When queries are implemented using Classic Query Engine (CQE), you need to be aware of how the query is optimized including materialization and index usage." />
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<meta name="description" content="When queries are implemented using Classic Query Engine (CQE), you need to be aware of how the query is optimized including materialization and index usage." />
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<meta name="DC.Relation" scheme="URI" content="performancept.htm" />
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<meta name="DC.Relation" scheme="URI" content="sqematerialize.htm" />
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<meta name="DC.Relation" scheme="URI" content="cqeoptimize.htm" />
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<meta name="DC.Relation" scheme="URI" content="cqeindex.htm" />
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<meta name="copyright" content="(C) Copyright IBM Corporation 1998, 2006" />
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<meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 1998, 2006" />
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<meta name="DC.Format" content="XHTML" />
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<meta name="DC.Identifier" content="cqe" />
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<meta name="DC.Language" content="en-us" />
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<!-- All rights reserved. Licensed Materials Property of IBM -->
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<!-- US Government Users Restricted Rights -->
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<!-- Use, duplication or disclosure restricted by -->
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<!-- GSA ADP Schedule Contract with IBM Corp. -->
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<link rel="stylesheet" type="text/css" href="./ibmdita.css" />
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<link rel="stylesheet" type="text/css" href="./ic.css" />
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<title>Queries using Classic Query Engine</title>
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</head>
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<body id="cqe"><a name="cqe"><!-- --></a>
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<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
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<h1 class="topictitle1">Queries using Classic Query Engine</h1>
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<div><p>When queries are implemented using Classic Query Engine (CQE),
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you need to be aware of how the query is optimized including materialization
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and index usage.</p>
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</div>
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<div>
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<ul class="ullinks">
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<li class="ulchildlink"><strong><a href="sqematerialize.htm">Materialization</a></strong><br />
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When running Classic Query Engine (CQE), a partitioned table is materialized under some conditions.</li>
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<li class="ulchildlink"><strong><a href="cqeoptimize.htm">CQE query optimization considerations</a></strong><br />
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The Classic Query Engine (CQE) optimizer optimizes the query using the first partition member in the partitioned table. This access method is used to access rows from all of the partitions.</li>
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<li class="ulchildlink"><strong><a href="cqeindex.htm">Index usage</a></strong><br />
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The Classic Query Engine (CQE) uses nonpartitioned indexes to implement queries.</li>
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</ul>
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<div class="familylinks">
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<div class="parentlink"><strong>Parent topic:</strong> <a href="performancept.htm" title="Queries that reference partitioned tables need to be carefully considered because partitioned tables are often very large. It is important to understand the effects of accessing multiple partitions on your system and applications.">Query performance and optimization</a></div>
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</div>
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</div>
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</body>
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</html>
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