Re: problem with pg_statistics - Mailing list pgsql-performance

From Manfred Koizar
Subject Re: problem with pg_statistics
Date
Msg-id h64mfv8quqjc19dv0ufm9oegj6p1rpeipp@4ax.com
Whole thread Raw
In response to Re: problem with pg_statistics  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: problem with pg_statistics  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-performance
On Thu, 26 Jun 2003 10:08:05 -0400, Tom Lane <tgl@sss.pgh.pa.us>
wrote:
>Andre Schubert <andre@km3.de> writes:
>> i think i need a little help with a problem with pg_statistic.
>
>Try reducing random_page_cost

With index scan cost being more than 25 * seq scan cost, I guess that
- all other things held equal - even random_page_cost = 1 wouldn't
help.

Andre might also want to experiment with effective_cache_size and with
ALTER TABLE ... SET STATISTICS.

Or there's something wrong with correlation?

Andre, what hardware is this running on?  What are the values of
shared_buffers, random_page_cost, effective_cache_size, ... ?  Could
you show us the result of

    SELECT * FROM pg_stats
     WHERE tablename = "tbl_traffic" AND attname = "time_stamp";

Servus
 Manfred

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