47 lines
3.7 KiB
HTML
47 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="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="Foreign key enforcement" />
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<meta name="abstract" content="The delete and update rules that you specify when you create a constraint apply to parent key changes. The database enforces a no-action rule on the insert and update operations to the foreign key in order to maintain referential integrity. The system enforces this rule on the insert and update operations to the foreign key to ensure that the value of every non-null foreign key matches the value of the parent key." />
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<meta name="description" content="The delete and update rules that you specify when you create a constraint apply to parent key changes. The database enforces a no-action rule on the insert and update operations to the foreign key in order to maintain referential integrity. The system enforces this rule on the insert and update operations to the foreign key to ensure that the value of every non-null foreign key matches the value of the parent key." />
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<meta name="DC.Relation" scheme="URI" content="rbaforzahfrcp.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="rbaforzahfrcq" />
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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>Foreign key enforcement</title>
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</head>
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<body id="rbaforzahfrcq"><a name="rbaforzahfrcq"><!-- --></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">Foreign key enforcement</h1>
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<div><p>The delete and update rules that you specify when
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you create a constraint apply to parent key changes. The database enforces
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a no-action rule on the insert and update operations to the foreign key in
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order to maintain referential integrity. The system enforces this rule on
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the insert and update operations to the foreign key to ensure that the value
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of every non-null foreign key matches the value of the parent key.</p>
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<p>The system returns a referential constraint violation if a matching parent
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key does not exist for the new foreign key value, and does not insert or update
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the dependent record. </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="rbaforzahfrcp.htm" title="The input/output (I/O) access for files that are associated with established and enabled constraints varies. It depends on whether the file contains the parent key or foreign key in the constraint relationship. The system enforces referential integrity enforcement on all parent and dependent file I/O requests.">Referential integrity enforcement</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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