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Re: improving my query plan

From: Chris <dmagick(at)gmail(dot)com>
To: Kevin Kempter <kevink(at)consistentstate(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: improving my query plan
Date: 2009-08-21 01:21:45
Message-ID: 4A8DF6A9.9040705@gmail.com (view raw or flat)
Thread:
Lists: pgsql-performance
Kevin Kempter wrote:
> Hi all;
> 
> 
> I have a simple query against two very large tables ( > 800million rows 
> in theurl_hits_category_jt table and 9.2 million in the url_hits_klk1 
> table )
> 
> 
> I have indexes on the join columns and I've run an explain.
> also I've set the default statistics to 250 for both join columns. I get 
> a very high overall query cost:

If you had an extra where condition it might be different, but you're 
just returning results from both tables that match up so doing a 
sequential scan is going to be the fastest way anyway.

-- 
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