62 lines
4.8 KiB
HTML
62 lines
4.8 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="Use floating-point fields in database file access paths" />
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<meta name="abstract" content="The collating sequence for records in a keyed database file depends on the presence of the SIGNED, UNSIGNED, and ABSVAL keywords in data description specifications (DDS). For floating-point fields, the sign is the farthest-left bit, the exponent is next, and the significant is last." />
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<meta name="description" content="The collating sequence for records in a keyed database file depends on the presence of the SIGNED, UNSIGNED, and ABSVAL keywords in data description specifications (DDS). For floating-point fields, the sign is the farthest-left bit, the exponent is next, and the significant is last." />
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<meta name="DC.subject" content="floating point field, use in access paths, field, using, floating point in access paths, access path, floating point fields, SIGNED (Signed) keyword, UNSIGNED (Unsigned) keyword, Unsigned (UNSIGNED) keyword, ABSVAL (Absolute Value) keyword, Absolute Value (ABSVAL) keyword, keyword, DDS, SIGNED (Signed), UNSIGNED (Unsigned), ABSVAL (Absolute Value), REFACCPTH (Reference Access Path Definition)" />
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<meta name="keywords" content="floating point field, use in access paths, field, using, floating point in access paths, access path, floating point fields, SIGNED (Signed) keyword, UNSIGNED (Unsigned) keyword, Unsigned (UNSIGNED) keyword, ABSVAL (Absolute Value) keyword, Absolute Value (ABSVAL) keyword, keyword, DDS, SIGNED (Signed), UNSIGNED (Unsigned), ABSVAL (Absolute Value), REFACCPTH (Reference Access Path Definition)" />
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<meta name="DC.Relation" scheme="URI" content="rbafoapath.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="rbafofpaccp" />
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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>Use floating-point fields in database file access paths</title>
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</head>
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<body id="rbafofpaccp"><a name="rbafofpaccp"><!-- --></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">Use floating-point fields in database file access paths</h1>
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<div><p>The collating sequence for records in a keyed database file depends
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on the presence of the SIGNED, UNSIGNED, and ABSVAL keywords in data description
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specifications (DDS). For floating-point fields, the sign is the farthest-left
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bit, the exponent is next, and the significant is last.</p>
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<div class="p">The collating sequence with UNSIGNED specified is: <ul><li>Positive real numbers—positive infinity</li>
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<li>Negative real numbers—negative infinity</li>
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</ul>
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</div>
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<p>A floating-point key field with the SIGNED keyword specified, or defaulted
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to, in DDS has an algebraic numeric sequence. The collating sequence is negative
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infinity—real numbers—positive infinity.</p>
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<p>A floating-point key field with the ABSVAL keyword specified in DDS has
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an absolute value numeric sequence.</p>
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<div class="p">The following floating-point collating sequences are observed: <ul><li>Zero (positive or negative) collates in the same manner as any other positive/negative
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real number.</li>
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<li>Negative zero collates before positive zero for SIGNED sequences.</li>
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<li>Negative and positive zero collate the same for ABSVAL sequences.</li>
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</ul>
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</div>
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<p>You cannot use not-a-number (*NAN) values in key fields. If you attempt
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this, and a *NAN value is detected in a key field during file creation, the
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file is not created.</p>
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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="rbafoapath.htm" title="These topics discuss the different ways of describing access paths for database files.">Describe access paths for database files</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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