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To: Wei Weng <wweng@kencast.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: Can you help with this JOIN? 
In-reply-to: <1022688374.26733.5.camel@Monet> 
References: <1022688374.26733.5.camel@Monet>
Comments: In-reply-to Wei Weng <wweng@kencast.com>
	message dated "29 May 2002 12:06:14 -0400"
Date: Wed, 29 May 2002 12:37:06 -0400
Message-ID: <24119.1022690226@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
X-Archive-Number: 200205/305
X-Sequence-Number: 7940

Wei Weng <wweng@kencast.com> writes:
> I have a massive join that takes something like 10 seconds to execute in
> Postgresql 7.2. Can any of gurus here help me improve it?

1. Have you vacuum analyzed these tables lately?  The row count
estimates look suspiciously low.

2. Please provide EXPLAIN ANALYZE output not just EXPLAIN.

			regards, tom lane