Re: Bad planner decision - bitmap scan instead of index - Mailing list pgsql-performance

From Michael Stone
Subject Re: Bad planner decision - bitmap scan instead of index
Date
Msg-id 20070817152326.GA3749@mathom.us
Whole thread Raw
In response to Re: Bad planner decision - bitmap scan instead of index  (Frank Schoep <frank@ffnn.nl>)
Responses Re: Bad planner decision - bitmap scan instead of index  (Frank Schoep <frank@ffnn.nl>)
List pgsql-performance
On Fri, Aug 17, 2007 at 10:43:18AM +0200, Frank Schoep wrote:
>On Aug 17, 2007, at 9:28 AM, hubert depesz lubaczewski wrote:
>(cost=0.00..37612.76 rows=14221 width=48) (actual time=0.125..13.686
>rows=2000 loops=1)
[snip]
>I'm not an expert at how the planner decides which query plan to use,

Neither am I. :) I do notice that the estimated number of rows is
significantly larger than the real number; you may want to bump up your
statistics a bit to see if it can estimate better.

Mike Stone

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