PostgreSQL TODO List
====================
Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us)
-Last updated: Sat Dec 17 13:06:57 EST 2005
+Last updated: Sat Dec 17 14:03:20 EST 2005
The most recent version of this document can be viewed at
http://www.postgresql.org/docs/faqs.TODO.html.
* Log statements where the optimizer row estimates were dramatically
different from the number of rows actually found?
-* 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. Some
- of these algorithms might be patented.
Miscellaneous Performance
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<h1><a name="section_1">PostgreSQL TODO List</a></h1>
<p>Current maintainer: Bruce Momjian (<a href="mailto:pgman@candle.pha.pa.us">pgman@candle.pha.pa.us</a>)<br/>
-Last updated: Sat Dec 17 13:06:57 EST 2005
+Last updated: Sat Dec 17 14:03:20 EST 2005
</p>
<p>The most recent version of this document can be viewed at<br/>
<a href="http://www.postgresql.org/docs/faqs.TODO.html">http://www.postgresql.org/docs/faqs.TODO.html</a>.
</p>
</li><li>Log statements where the optimizer row estimates were dramatically
different from the number of rows actually found?
- </li><li>Allow star join optimizations
-<p> 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. Some
- of these algorithms might be patented.
-</p>
</li></ul>
<h1><a name="section_21">Miscellaneous Performance</a></h1>
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