ibm-information-center/dist/eclipse/plugins/i5OS.ic.rzajq_5.4.0.1/cpi4329.htm

76 lines
4.4 KiB
HTML

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html lang="en-us" xml:lang="en-us">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta name="security" content="public" />
<meta name="Robots" content="index,follow" />
<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))' />
<meta name="DC.Type" content="reference" />
<meta name="DC.Title" content="CPI4329 - Arrival sequence access was used for &amp;12 &amp;13" />
<meta name="DC.Relation" scheme="URI" content="pimes.htm" />
<meta name="copyright" content="(C) Copyright IBM Corporation 1998, 2006" />
<meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 1998, 2006" />
<meta name="DC.Format" content="XHTML" />
<meta name="DC.Identifier" content="cpi4329" />
<meta name="DC.Language" content="en-us" />
<!-- All rights reserved. Licensed Materials Property of IBM -->
<!-- US Government Users Restricted Rights -->
<!-- Use, duplication or disclosure restricted by -->
<!-- GSA ADP Schedule Contract with IBM Corp. -->
<link rel="stylesheet" type="text/css" href="./ibmdita.css" />
<link rel="stylesheet" type="text/css" href="./ic.css" />
<title>CPI4329 - Arrival sequence access was used for &amp;12 &amp;13</title>
</head>
<body id="cpi4329"><a name="cpi4329"><!-- --></a>
<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
<h1 class="topictitle1">CPI4329 - Arrival sequence access was used for &amp;12 &amp;13</h1>
<div>
<div class="tablenoborder"><table cellpadding="4" cellspacing="0" summary="" frame="border" border="1" rules="all"><thead align="left"><tr><th colspan="2" align="center" valign="middle" id="d0e16">CPI4329</th>
</tr>
</thead>
<tbody><tr valign="middle"><td valign="middle" width="26.02040816326531%" headers="d0e16 ">Message Text:</td>
<td valign="middle" width="73.9795918367347%" headers="d0e16 ">Arrival sequence access was used for &amp;12 &amp;13.</td>
</tr>
<tr valign="middle"><td valign="middle" width="26.02040816326531%" headers="d0e16 ">Cause Text:</td>
<td valign="middle" width="73.9795918367347%" headers="d0e16 ">Arrival sequence access was used to select records from member &amp;2
of file &amp;13 in library &amp;1. <p></p>
If file &amp;13 in library &amp;1
is a logical file then member &amp;8 of physical file &amp;6 in library &amp;7
is the actual file from which records are being selected. <p></p>
A
file name starting with *N or *QUERY for the file indicates it is a temporary
file.</td>
</tr>
<tr valign="middle"><td valign="middle" width="26.02040816326531%" headers="d0e16 ">Recovery Text:</td>
<td valign="middle" width="73.9795918367347%" headers="d0e16 ">The use of an access path may improve the performance of the query
if record selection is specified. <p></p>
If an access path does not
exist, you may want to create one whose left-most key fields match fields
in the record selection. Matching more key fields in the access path with
fields in the record selection will result in improved performance.
<p></p>
Generally, to force the use of an existing access path, specify order
by fields that match the left-most key fields of that access path. <p></p>
For
more information refer to <a href="rzajqdta.htm#rzajqdta">Data access on DB2 UDB for iSeries: data access paths and methods</a>.</td>
</tr>
</tbody>
</table>
</div>
<div class="section"><p>If an index does not exist, you may want to create
one whose key column matches one of the columns in the row selection. You
should only create an index if the row selection (WHERE clause) selects 20%
or fewer rows in the table. To force the use of an existing index, change
the ORDER BY clause of the query to specify the first key column of the index,
or ensure that the query is running under a first I/O environment.</p>
</div>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="pimes.htm" title="You can evaluate the structure and performance of the given SQL statements in a program using informational messages put in the job log by the database manager.">Query optimization performance information messages</a></div>
</div>
</div>
</body>
</html>