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

108 lines
7.4 KiB
HTML
Raw Normal View History

2024-04-02 14:02:31 +00:00
<?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="Starting Visual Explain" />
<meta name="abstract" content="There are two ways to invoke the Visual Explain tool. The first, and most common, is through iSeries Navigator. The second is through the Visual Explain (QQQVEXPL) API." />
<meta name="description" content="There are two ways to invoke the Visual Explain tool. The first, and most common, is through iSeries Navigator. The second is through the Visual Explain (QQQVEXPL) API." />
<meta name="DC.subject" content="Visual Explain, starting" />
<meta name="keywords" content="Visual Explain, starting" />
<meta name="DC.Relation" scheme="URI" content="visexpl.htm" />
<meta name="DC.Relation" scheme="URI" content="../apis/qqqvexpl.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="rzajqstartve" />
<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>Starting Visual Explain</title>
</head>
<body id="rzajqstartve"><a name="rzajqstartve"><!-- --></a>
<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
<h1 class="topictitle1">Starting Visual Explain</h1>
<div><p>There are two ways to invoke the Visual Explain tool. The first,
and most common, is through iSeries™ Navigator. The second is through the Visual
Explain (QQQVEXPL) API.</p>
<div class="section"><p>You can start Visual Explain from any of the following windows
in <span class="keyword">iSeries Navigator</span>: </p>
<img src="./delta.gif" alt="Start of change" /><ul><li>Enter an SQL statement in the <span class="uicontrol">Run SQL Scripts</span> window.
Select the statement and choose <span class="uicontrol">Explain</span> from the context
menu, or select <span class="uicontrol">Run and Explain</span> from the <span class="uicontrol">Visual
Explain</span> menu.</li>
<li>Expand the list of available SQL Performance Monitors. Right-click a detailed
SQL Performance Monitor and choose the <span class="uicontrol">Show Statements</span> option.
Select filtering information and select the statement in the List of Statements
window. Click <span class="uicontrol">Run Visual Explain</span>. You can also start
an SQL Performance Monitor from Run SQL Scripts. Select <span class="uicontrol">Start SQL
Performance monitor</span> from the <span class="uicontrol">Monitor</span> menu.</li>
<li>Start the Current SQL for a Job function by right-clicking <span class="uicontrol">Databases</span> and
select <span class="uicontrol">Current SQL for a Job</span>. Select a job from the
list and click <span class="uicontrol">SQL Statement</span>. When the SQL is displayed
in the lower pane, you can start Visual Explain by clicking <span class="uicontrol">Run
Visual Explain</span>.</li>
<li>Right-click SQL Plan Cache and select <span class="uicontrol">Show Statements</span>.
Select filtering information and select the statement in the List of Statements
window. Click <span class="uicontrol">Run Visual Explain</span>. </li>
<li>Expand the list of available SQL Plan Cache Snapshots. Right-click a snapshot
and select <span class="uicontrol">Show Statements</span>. Select filtering information
and select the statement in the List of Statements window. Click <span class="uicontrol">Run
Visual Explain</span>. </li>
</ul><img src="./deltaend.gif" alt="End of change" />
</div>
<div class="section"><p><img src="./delta.gif" alt="Start of change" />You have three options when running Visual Explain
from Run SQL Scripts.<img src="./deltaend.gif" alt="End of change" /></p>
<dl><dt class="dlterm">Visual Explain only</dt>
<dd>This option allows you to explain the query without actually running it.
The data displayed represents the query optimizer's estimates.<div class="note"><span class="notetitle">Note:</span> When using
the Explain only option of Visual Explain from Run SQL Scripts in iSeries Navigator,
some queries receive an error code 93 stating that they are too complex for
displaying in Visual Explain. You can circumvent this by selecting the "Run
and Explain" option. </div>
</dd>
<dt class="dlterm">Run and Explain</dt>
<dd>If you select Run and Explain, the query is run by the system before the
diagram is displayed. This option may take a significant amount of time, but
the information displays is more complete and accurate.</dd>
<dt class="dlterm">Explain while running</dt>
<dd>For long running queries, you can choose to start Visual Explain while
the query is running. By refreshing the Visual Explain diagram, you can view
the progress of the query.</dd>
</dl>
<p>In addition, a database monitor table that was not created
as a result of using iSeries Navigator can be explained through iSeries Navigator.
First you must import the database monitor table into iSeries Navigator. To do this, right-click
the SQL Performance Monitors and choose the <span class="uicontrol">Import</span> option.
Specify a name for the performance monitor (name it will be known by within iSeries Navigator)
and the qualified name of the database monitor table. Be sure to select Detailed
as the type of monitor. Detailed represents the file-based (STRDBMON) monitor
while Summary represents the memory-resident monitor (which is not supported
by Visual Explain). Once the monitor has been imported, follow the steps to
start Visual Explain from within iSeries Navigator.</p>
</div>
<div class="section"><p>You can save your Visual Explain information as an SQL Performance
monitor, which can be useful if you started the query from Run SQL Scripts
and want to save the information for later comparison. Select <span class="uicontrol">Save
as Performance monitor</span> from the <span class="uicontrol">File</span> menu.</p>
</div>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="visexpl.htm" title="You can use the Visual Explain tool with iSeries Navigator to create a query graph that graphically displays the implementation of an SQL statement. You can use this tool to see information about both static and dynamic SQL statements. Visual Explain supports the following types of SQL statements: SELECT, INSERT, UPDATE, and DELETE.">View the implementation of your queries with Visual Explain</a></div>
</div>
<div class="relinfo"><strong>Related information</strong><br />
<div><a href="../apis/qqqvexpl.htm">Visual Explain (QQQVEXPL) API</a></div>
</div>
</div>
</body>
</html>