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Date: Sun, 18 Mar 2001 10:42:57 -0800 (PST)
From: David Olbersen <dave@slickness.org>
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To: "Fernando Eduardo B. L. e Carvalho" <feblec@ig.com.br>
cc: Postgresql <pgsql-sql@postgresql.org>
Subject: Re: Select very slow...
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On Sun, 18 Mar 2001, Fernando Eduardo B. L. e Carvalho wrote:

>   select  p.city,count(*) from sales s, person p where s.doc = p.doc
> group by p.city;
>
>    Anyone help-me?

1: VACUUM ANALYZE sales
   VACUUM ANALYZE person;

2: That 'count(*)' is going to be slow.
   Try counting a column that's indexed (p.doc might work?)

3: EXPLAIN <your select from above>;
   That should give you some hints on what to optimize.

-- Dave