120 lines
9.7 KiB
HTML
120 lines
9.7 KiB
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<meta name="DC.Title" content="Examples of indexes" />
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<meta name="abstract" content="The following index examples are provided to help you create effective indexes." />
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<meta name="description" content="The following index examples are provided to help you create effective indexes." />
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<meta name="copyright" content="(C) Copyright IBM Corporation 1998, 2006" />
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<link rel="stylesheet" type="text/css" href="./ic.css" />
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<title>Examples of indexes</title>
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</head>
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<body id="indexxmp"><a name="indexxmp"><!-- --></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">Examples of indexes</h1>
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<div><p>The following index examples are provided to help you create effective
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indexes.</p>
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<div class="section"><p>For the purposes of the examples, assume that three indexes are
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created.</p>
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</div>
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<div class="section"><p>Assume that an index HEXIX was created with *HEX as the sort sequence.
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</p>
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<pre> <strong>CREATE INDEX</strong> HEXIX <strong>ON</strong> STAFF (JOB)</pre>
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</div>
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<div class="section"><p>Assume that an index UNQIX was created with a unique-weight sort
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sequence. </p>
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<pre> <strong>CREATE INDEX</strong> UNQIX <strong>ON</strong> STAFF (JOB)</pre>
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</div>
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<div class="section"><p>Assume that an index SHRIX was created with a shared-weight sort
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sequence. </p>
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<pre> <strong>CREATE INDEX</strong> SHRIX <strong>ON</strong> STAFF (JOB)</pre>
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</div>
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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="nosort.htm">Index example: Equals selection with no sort sequence table</a></strong><br />
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Equals selection with no sort sequence table (SRTSEQ(*HEX)).</li>
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<li class="ulchildlink"><strong><a href="uniqueweight.htm">Index example: Equals selection with a unique-weight sort sequence table</a></strong><br />
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Equals selection with a unique-weight sort sequence table (SRTSEQ(*LANGIDUNQ) LANGID(ENU)).</li>
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<li class="ulchildlink"><strong><a href="sharedweight.htm">Index example: Equal selection with a shared-weight sort sequence table</a></strong><br />
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Equal selection with a shared-weight sort sequence table (SRTSEQ(*LANGIDSHR) LANGID(ENU)).</li>
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<li class="ulchildlink"><strong><a href="greater.htm">Index example: Greater than selection with a unique-weight sort sequence table</a></strong><br />
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Greater than selection with a unique-weight sort sequence table (SRTSEQ(*LANGIDUNQ) LANGID(ENU)).</li>
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<li class="ulchildlink"><strong><a href="joinsel.htm">Index example: Join selection with a unique-weight sort sequence table</a></strong><br />
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Join selection with a unique-weight sort sequence table (SRTSEQ(*LANGIDUNQ) LANGID(ENU)).</li>
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<li class="ulchildlink"><strong><a href="joinselshared.htm">Index example: Join selection with a shared-weight sort sequence table</a></strong><br />
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Join selection with a shared-weight sort sequence table (SRTSEQ(*LANGIDSHR) LANGID(ENU)).</li>
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<li class="ulchildlink"><strong><a href="orderingnosort.htm">Index example: Ordering with no sort sequence table</a></strong><br />
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Ordering with no sort sequence table (SRTSEQ(*HEX)).</li>
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<li class="ulchildlink"><strong><a href="orderinguniweight.htm">Index example: Ordering with a unique-weight sort sequence table</a></strong><br />
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Ordering with a unique-weight sort sequence table (SRTSEQ(*LANGIDUNQ) LANGID(ENU)).</li>
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<li class="ulchildlink"><strong><a href="orderingshared.htm">Index example: Ordering with a shared-weight sort sequence table</a></strong><br />
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Ordering with a shared-weight sort sequence table (SRTSEQ(*LANGIDSHR) LANGID(ENU)).</li>
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<li class="ulchildlink"><strong><a href="ordalwcpydta.htm">Index example: Ordering with ALWCPYDTA(*OPTIMIZE) and a unique-weight sort sequence table</a></strong><br />
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Ordering with ALWCPYDTA(*OPTIMIZE) and a unique-weight sort sequence table (SRTSEQ(*LANGIDUNQ) LANGID(ENU)).</li>
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<li class="ulchildlink"><strong><a href="groupnosort.htm">Index example: Grouping with no sort sequence table</a></strong><br />
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Grouping with no sort sequence table (SRTSEQ(*HEX)).</li>
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<li class="ulchildlink"><strong><a href="groupunique.htm">Index example: Grouping with a unique-weight sort sequence table</a></strong><br />
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Grouping with a unique-weight sort sequence table (SRTSEQ(*LANGIDUNQ) LANGID(ENU)).</li>
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<li class="ulchildlink"><strong><a href="groupshared.htm">Index example: Grouping with a shared-weight sort sequence table</a></strong><br />
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Grouping with a shared-weight sort sequence table (SRTSEQ(*LANGIDSHR) LANGID(ENU)).</li>
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<li class="ulchildlink"><strong><a href="ordgrpsame.htm">Index example: Ordering and grouping on the same columns with a unique-weight sort sequence table</a></strong><br />
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Ordering and grouping on the same columns with a unique-weight sort sequence table (SRTSEQ(*LANGIDUNQ) LANGID(ENU)).</li>
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<li class="ulchildlink"><strong><a href="ordgrpalwcpydta.htm">Index example: Ordering and grouping on the same columns with ALWCPYDTA(*OPTIMIZE) and a unique-weight sort sequence table</a></strong><br />
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Ordering and grouping on the same columns with ALWCPYDTA(*OPTIMIZE) and a unique-weight sort sequence table (SRTSEQ(*LANGIDUNQ) LANGID(ENU)).</li>
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<li class="ulchildlink"><strong><a href="ordgrpshared.htm">Index example: Ordering and grouping on the same columns with a shared-weight sort sequence table</a></strong><br />
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Ordering and grouping on the same columns with a shared-weight sort sequence table (SRTSEQ(*LANGIDSHR) LANGID(ENU)).</li>
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<li class="ulchildlink"><strong><a href="ordgrpsharedweight.htm">Index example: Ordering and grouping on the same columns with ALWCPYDTA(*OPTIMIZE) and a shared-weight sort sequence table</a></strong><br />
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Ordering and grouping on the same columns with ALWCPYDTA(*OPTIMIZE) and a shared-weight sort sequence table (SRTSEQ(*LANGIDSHR) LANGID(ENU).</li>
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<li class="ulchildlink"><strong><a href="ordgrpdiffcols.htm">Index example: Ordering and grouping on different columns with a unique-weight sort sequence table</a></strong><br />
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Ordering and grouping on different columns with a unique-weight sort sequence table (SRTSEQ(*LANGIDUNQ) LANGID(ENU)).</li>
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<li class="ulchildlink"><strong><a href="ordgrpdiffalwcpydta.htm">Index example: Ordering and grouping on different columns with ALWCPYDTA(*OPTIMIZE) and a unique-weight sort sequence table</a></strong><br />
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Ordering and grouping on different columns with ALWCPYDTA(*OPTIMIZE) and a unique-weight sort sequence table (SRTSEQ(*LANGIDUNQ) LANGID(ENU)).</li>
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<li class="ulchildlink"><strong><a href="ordgrpshweightsort.htm">Index example: Ordering and grouping on different columns with ALWCPYDTA(*OPTIMIZE) and a shared-weight sort sequence table</a></strong><br />
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Ordering and grouping on different columns with ALWCPYDTA(*OPTIMIZE) and a shared-weight sort sequence table (SRTSEQ(*LANGIDSHR) LANGID(ENU)).</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="efindex.htm" title="DB2 Universal Database for iSeries provides two basic means for accessing tables: a table scan and an index-based retrieval. Index-based retrieval is typically more efficient than table scan when less than 20% of the table rows are selected.">Creating an index strategy</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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