59 lines
3.7 KiB
HTML
59 lines
3.7 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="DC.Type" content="reference" />
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<meta name="DC.Title" content="Avoid character string padding" />
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<meta name="abstract" content="Try to use the same data length when comparing a fixed-length character string column value to a host variable or constant value. DB2 Universal Database for iSeries does not use an index if the constant value or host variable is longer than the column length." />
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<meta name="description" content="Try to use the same data length when comparing a fixed-length character string column value to a host variable or constant value. DB2 Universal Database for iSeries does not use an index if the constant value or host variable is longer than the column length." />
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<meta name="DC.Relation" scheme="URI" content="rzajqeffectindex.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="avoidcharpad" />
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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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<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>Avoid character string padding</title>
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</head>
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<body id="avoidcharpad"><a name="avoidcharpad"><!-- --></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">Avoid character string padding</h1>
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<div><p>Try to use the same data length when comparing a fixed-length character
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string column value to a host variable or constant value. <span class="keyword">DB2 Universal Database™ for iSeries™</span> does
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not use an index if the constant value or host variable is longer than the
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column length.</p>
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<div class="section"><p>For example, EMPNO is CHAR(6) and DEPTNO is CHAR(3). For example,
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when using SQL, specify the following: </p>
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<pre>… <strong>WHERE</strong> EMPNO > '000300' <strong>AND</strong>
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DEPTNO < 'E20'</pre>
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</div>
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<div class="section"><p>instead of </p>
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<pre>… <strong>WHERE</strong> EMPNO > '000300 ' <strong>AND</strong>
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DEPTNO < 'E20 '</pre>
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</div>
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<div class="section"><p>When using the OPNQRYF command, specify:</p>
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</div>
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<div class="section"><div class="p"> <pre>... QRYSLT('EMPNO *GT "000300" *AND DEPTNO *LT "E20"')</pre>
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</div>
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</div>
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<div class="section"><div class="p">instead of <pre>... QRYSLT('EMPNO *GT "000300" *AND DEPTNO *LT "E20"')</pre>
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</div>
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</div>
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</div>
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<div>
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<div class="familylinks">
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<div class="parentlink"><strong>Parent topic:</strong> <a href="rzajqeffectindex.htm" title="The following topics provide suggestions that will help you to design code which allows DB2 Universal Database for iSeries to take advantage of available indexes:">Coding for effective indexes</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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