Re: SELECT with MANY tables - Mailing list pgsql-bugs

From Javier Carlos
Subject Re: SELECT with MANY tables
Date
Msg-id 1069875722.3fc5020a6cfd9@correo.insp.mx
Whole thread Raw
In response to Re: SELECT with MANY tables  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-bugs
Quoting Tom Lane <tgl@sss.pgh.pa.us>:

> Javier Carlos <fjcarlos@correo.insp.mx> writes:
> >    When I make a SELECT with many tables (more than 12), postgresql eats
> all my
> > %CPU and I've waited more than 1 hour and stays the same. The weird thing
> is
> > that with 10 tables the same select with the same joins only takes about 5
> > seconds. First I thought that It was a problem related with one specific
> table,
> > but I've changed in the SELECT the tables and while the number of tables
> remains
> > less than 12 all is ok.
>
> Hm.  Are you using the default GEQO settings, or something custom?
>
>             regards, tom lane
>

    Hi,

    I'm using the default GEQO settings:

#geqo = true
#geqo_threshold = 11
#geqo_effort = 1
#geqo_generations = 0
#geqo_pool_size = 0
#geqo_selection_bias = 2.0

   Yesterday I solved the problem recreating the database and remigrating all
the information. I think that the problem was the pg_dumpall of PostgreSQL
7.3.4, maybe corrupted some indexes.

   Regards,

   Javier



---------------------------------------
Instituto Nacional de Salud Pública
Evaluación Oportunidades - DataWeb
http://evaloportunidades.insp.mx

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