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Re: Join problem

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Silke Trissl <trissl(at)informatik(dot)hu-berlin(dot)de>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: Join problem
Date: 2004-04-28 12:52:20
Message-ID: (view raw, whole thread or download thread mbox)
Lists: pgsql-performance
Silke Trissl <trissl(at)informatik(dot)hu-berlin(dot)de> writes:
> I found out, that the change of the operator from '~*' to '=' for the 
> item.description brought a great boost in performance (425 secs to 1 
> sec!), but not in cost (Query plans at the end).

The main problem seems to be bad estimation of the number of rows
extracted from the item table.  Have you ANALYZEd that table lately?

			regards, tom lane

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