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Re: bitmap-index-scan slower than normal index scan - Mailing list pgsql-performance

From A. Kretschmer
Subject Re: bitmap-index-scan slower than normal index scan
Date
Msg-id 20070712050631.GA2729@a-kretschmer.de
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In response to Re: bitmap-index-scan slower than normal index scan  (Andreas Kretschmer <akretschmer@spamfence.net>)
List pgsql-performance
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am  Wed, dem 11.07.2007, um 22:19:58 +0200 mailte Andreas Kretschmer folgendes:
> > Also, part of the problem here looks to be an overestimate of the number
> > of rows matching ab = 347735.  It might help to increase the statistics
> > target for that column.
>
> I will try this tomorrow and inform you about the result. I've never
> done this before, i need to read the docs about this.

Okay, done, setting to 100 (thanks to mastermind) and now i got an Index
Scan using idx_ab with a total runtime: 0.330 ms.

Great, thanks. And yes, i will update soon...


Andreas
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