> -----Original Message-----
> From: hyelluas [mailto:helen_yelluas@mcafee.com]
> Sent: Monday, August 15, 2011 2:33 PM
> To: pgsql-performance@postgresql.org
> Subject: Re: How to see memory usage using explain analyze ?
>
> Igor,
>
> thank you , my tests showed better performance against the larger
> summary
> tables when I splited the index for datasource_id & datex , I use to
> have a
> composed index.
>
> Regarding that index statistics - should I analyze the tables? I
> thought
> auto vacuum takes care of it.
>
> helen
>
> --
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> explain-analyze-tp4694962p4701919.html
> Sent from the PostgreSQL - performance mailing list archive at
> Nabble.com.
But, having different sets of indexes, you can't compare execution
plans.
In regards to statistics, you could try to ANALYZE table manually, may
be increasing "default_statistics_target".
From the docs:
"default_statistics_target (integer)
Sets the default statistics target for table columns that have not
had a column-specific target set via ALTER TABLE SET STATISTICS. Larger
values increase the time needed to do ANALYZE, but might improve the
quality of the planner's estimates. The default is 10. For more
information on the use of statistics by the PostgreSQL query planner,
refer to Section 14.2."
HTH,
Igor