From: Andreas Kretschmer <akretschmer@spamfence.net>
To: pgsql-sql@postgresql.org
Subject: Re: Multi-column index not used, new flipped column index is
Date: Wed, 10 May 2006 20:32:35 +0200
Message-ID: <20060510183235.GB18485@KanotixBox> (raw)
In-Reply-To: <446218D2.8030002@logix-tt.com>
References: <20060510162143.96628.qmail@web50306.mail.yahoo.com>
<446218D2.8030002@logix-tt.com>
Markus Schaber <schabi@logix-tt.com> schrieb:
> Bitmap Index Scans can be your solution, but AFAIK they were invented in
> 8.1.
Right.
>
> For bitmap index scans, you have one index on fkColumnOne and one on
> fkColumnTwo, and the query planner knows to combine them when both
> columns are given in a WHERE clause.
Yeah! The Bitmap Index Scan is a great thing. With some selects i have a
performance-boost from 5 to 10, compared with 8.0.
Andreas
--
Really, I'm not out to destroy Microsoft. That will just be a completely
unintentional side effect. (Linus Torvalds)
"If I was god, I would recompile penguin with --enable-fly." (unknow)
Kaufbach, Saxony, Germany, Europe. N 51.05082°, E 13.56889°
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To: pgsql-sql@postgresql.org
Cc: akretschmer@spamfence.net
Subject: Re: Multi-column index not used, new flipped column index is
In-Reply-To: <20060510183235.GB18485@KanotixBox>
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