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Commit9e9a844

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* Allow star join optimizations While our bitmap scan allows multiple indexes to be joined to get to heap rows, a star joins allows multiple dimension _tables_ to be joined to index into a larger main fact table. The join is usually performed by either creating a cartesian product of all the dimmension tables and doing a single join on that product or using subselects to create bitmaps of each dimmension table match and merge the bitmaps to perform the join on the fact table.
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‎doc/TODO

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PostgreSQL TODO List
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====================
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Current maintainer:Bruce Momjian (pgman@candle.pha.pa.us)
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Last updated:Sat Dec 1709:18:30 EST 2005
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Last updated:Sat Dec 1711:43:02 EST 2005
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The most recent version of this document can be viewed at
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http://www.postgresql.org/docs/faqs.TODO.html.
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* Log statements where the optimizer row estimates were dramatically
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different from the number of rows actually found?
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* Allow star join optimizations
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While our bitmap scan allows multiple indexes to be joined to get
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to heap rows, a star joins allows multiple dimension _tables_ to
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be joined to index into a larger main fact table. The join is
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usually performed by either creating a cartesian product of all
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the dimmension tables and doing a single join on that product or
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using subselects to create bitmaps of each dimmension table match
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and merge the bitmaps to perform the join on the fact table.
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Miscellaneous Performance

‎doc/src/FAQ/TODO.html

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<bodybgcolor="#FFFFFF"text="#000000"link="#FF0000"vlink="#A00000"alink="#0000FF">
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<h1><aname="section_1">PostgreSQL TODO List</a></h1>
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<p>Current maintainer: Bruce Momjian (<ahref="mailto:pgman@candle.pha.pa.us">pgman@candle.pha.pa.us</a>)<br/>
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Last updated: Sat Dec 1709:18:30 EST 2005
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Last updated: Sat Dec 1711:43:02 EST 2005
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</p>
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<p>The most recent version of this document can be viewed at<br/>
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<ahref="http://www.postgresql.org/docs/faqs.TODO.html">http://www.postgresql.org/docs/faqs.TODO.html</a>.
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</p>
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</li><li>Log statements where the optimizer row estimates were dramatically
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different from the number of rows actually found?
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</li><li>Allow star join optimizations
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<p> While our bitmap scan allows multiple indexes to be joined to get
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to heap rows, a star joins allows multiple dimension _tables_ to
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be joined to index into a larger main fact table. The join is
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usually performed by either creating a cartesian product of all
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the dimmension tables and doing a single join on that product or
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using subselects to create bitmaps of each dimmension table match
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and merge the bitmaps to perform the join on the fact table.
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</p>
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</li></ul>
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<h1><aname="section_21">Miscellaneous Performance</a></h1>
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