58 lines
3.8 KiB
HTML
58 lines
3.8 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 name="DC.Type" content="concept" />
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<meta name="DC.Title" content="Precautions to take when coding trigger programs" />
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<meta name="abstract" content="Trigger programs can be very powerful. But you must take caution when coding trigger programs." />
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<meta name="description" content="Trigger programs can be very powerful. But you must take caution when coding trigger programs." />
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<meta name="DC.Relation" scheme="URI" content="rbaforzahftrb2.htm" />
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<meta name="DC.Relation" scheme="URI" content="rbafotrgfn.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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<!-- All rights reserved. Licensed Materials Property of IBM -->
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<title>Precautions to take when coding trigger programs</title>
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</head>
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<body id="rbaforzahftre"><a name="rbaforzahftre"><!-- --></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">Precautions to take when coding trigger programs</h1>
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<div><p>Trigger programs can be very powerful. But you must take caution
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when coding trigger programs. </p>
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<p>Be careful when designing trigger programs that access a system resource,
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such as a tape drive. For instance, a trigger program that copies record changes
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to tape media can be useful, but the program itself cannot detect if the tape
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drive is ready or if it contains the correct tape. You must take these kinds
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of resource issues into considerations when designing trigger programs.</p>
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<p>In addition, use read triggers with extreme caution. Using
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a read trigger causes a trigger to be called for every record that is read.
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During a query, this means that triggers can be called many times as records
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are processed multiple times by the query. This can impact system performance.</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="rbafotrgfn.htm">Functions to use with care in trigger programs</a></strong><br />
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Some control language (CL) commands and functions are not recommended in a trigger program and need to be carefully considered if they are to be used.</li>
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<li class="ulchildlink"><strong><a href="rbafotrgncmd.htm">Commands, statements, and operations that you cannot use in trigger programs</a></strong><br />
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A trigger program cannot include some commands, statements, and operations.</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="rbaforzahftrb2.htm" title="These topics discuss recommendations, precautions, and error messages for trigger programs. Information about monitoring and commitment control is also included.">Other important information about working with triggers</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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