56 lines
4.3 KiB
HTML
56 lines
4.3 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 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="Referential integrity enforcement" />
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<meta name="abstract" content="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." />
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<meta name="description" content="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." />
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<meta name="DC.Relation" scheme="URI" content="rbaforzahfrca.htm" />
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<meta name="DC.Relation" scheme="URI" content="rbaforzahfrcq.htm" />
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<meta name="DC.Relation" scheme="URI" content="rbaforzahfrcr.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="rbaforzahfrcp" />
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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>Referential integrity enforcement</title>
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</head>
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<body id="rbaforzahfrcp"><a name="rbaforzahfrcp"><!-- --></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">Referential integrity enforcement</h1>
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<div><p>The input/output (I/O) access for files that are associated with
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established and enabled constraints varies. It depends on whether the file
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contains the parent key or foreign key in the constraint relationship. The
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system enforces referential integrity enforcement on all parent and dependent
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file I/O requests.</p>
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<p>The database enforces constraint rules for all I/O requests whether from
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application programs or system commands (such as the Initialize Physical File
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Member (INZPFM) command) or SQL statements or file I/O utilities
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(such as STRSEU).</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="rbaforzahfrcq.htm">Foreign key enforcement</a></strong><br />
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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.</li>
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<li class="ulchildlink"><strong><a href="rbaforzahfrcr.htm">Parent key enforcement</a></strong><br />
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The rules that you specify for the referential constraint determine how the database processes the delete and update operations on the parent key. The system enforces the unique attribute of a parent key on all parent file I/O.</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="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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