53 lines
3.3 KiB
HTML
53 lines
3.3 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 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="Details: Ensure data integrity with referential constraints" />
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<meta name="abstract" content="You might want to use referential integrity in your database management system for several reasons." />
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<meta name="description" content="You might want to use referential integrity in your database management system for several reasons." />
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<meta name="DC.Relation" scheme="URI" content="rbaforzahfrca.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="rbaforzahfrcb" />
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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>Details: Ensure data integrity with referential constraints</title>
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</head>
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<body id="rbaforzahfrcb"><a name="rbaforzahfrcb"><!-- --></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">Details: Ensure data integrity with referential constraints</h1>
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<div><p>You might want to use referential integrity in your database management
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system for several reasons.</p>
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<div class="p">You might want to ensure data integrity with referential constraints<ul><li>To make sure that data values between files meet the rules of your business.
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For example, consider a business that maintains a list of customers in one
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file and a list of their accounts in another file. It does not make sense
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to allow the addition of an account if an associated customer does not exist.
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Likewise, it is not reasonable to delete a customer until you delete all of
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their accounts.</li>
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<li>To be able to define the relationships between data values.</li>
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<li>To have the system enforce the data relationships no matter what application
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makes changes.</li>
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<li>To improve the performance of integrity checks that are made at a high-level
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language (HLL) or SQL level by moving the checking into the database.</li>
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</ul>
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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="rbaforzahfrca.htm" title="These topics discuss how to use referential constraints in your database to ensure that it contains only valid data.">Ensure data integrity with referential constraints</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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