Re: SOLVED: Where clause limited to 8 items?

From: "Henry Combrinck" <henry(at)metroweb(dot)co(dot)za>
To: "Stephan Szabo" <sszabo(at)megazone(dot)bigpanda(dot)com>
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: SOLVED: Where clause limited to 8 items?
Date: 2004-10-20 06:58:04
Message-ID: 15256.168.210.90.180.1098255484.squirrel@airmail.metroweb.co.za
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>
> Check the estimated number of rows returned. It's presumably believing
> that the a sequential scan will be cheaper for the estimated number of
> rows.
>
> If the estimated number of rows is significantly off, you may wish to
> change the statistics target (see ALTER TABLE) for col1 and analyze the
> table again.
>
> If it still is choosing a sequential scan over an index scan and the
> number of rows is similar, you may want to look at the "random_page_cost"
> variable. You have to be careful not too lower it too far that other
> queries are pessimized the other direction, but some experimentation
> comparing the real times and estimated costs of queries with and without
> enable_seqscan=off may help.

Thanks for the detailed response! Your suggestion was spot-on.

Regards
Henry

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