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Re: Forcing more agressive index scans for BITMAP AND - Mailing list pgsql-performance

From Matthew
Subject Re: Forcing more agressive index scans for BITMAP AND
Date
Msg-id Pine.LNX.4.64.0804041137500.20402@aragorn.flymine.org
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In response to Forcing more agressive index scans for BITMAP AND  (Ow Mun Heng <Ow.Mun.Heng@wdc.com>)
Responses Re: Forcing more agressive index scans for BITMAP AND
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On Fri, 4 Apr 2008, Ow Mun Heng wrote:
> select * from table
> where A=X
> and B = Y
> and C = Z
> and D = AA
> and E = BB

This may not be the answer you're looking for, but if you create a
multi-coloumn index, it should be able to make your query run fast:

CREATE INDEX foo ON table (A, B, C, D, E);

It'll certainly be faster than building a bitmap for the contents of five
separate indexes.

Matthew

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