From: Tom Lane <tgl@sss.pgh.pa.us>
To: John A Meinel <john@arbash-meinel.com>
Cc: Dan Harris <fbsd@drivefaster.net>
Cc: pgsql-performance@postgresql.org
Subject: Re: slow joining very large table to smaller ones
Date: Thu, 14 Jul 2005 19:30:02 -0400
Message-ID: <5708.1121383802@sss.pgh.pa.us> (raw)
In-Reply-To: <42D6F177.3000002@arbash-meinel.com>
References: <46AF8F35-B735-4DFA-BA0A-AC82B5DA3CCE@drivefaster.net>
<42D687E5.7080202@arbash-meinel.com>
<C3470621-9DB0-444A-BAD1-F9995E0142FB@drivefaster.net>
<42D6F177.3000002@arbash-meinel.com>
John A Meinel <john@arbash-meinel.com> writes:
> What I don't understand is that the planner is actually estimating that
> joining against the new table is going to *increase* the number of
> returned rows.
It evidently thinks that incidentid in the k_r table is pretty
nonunique. We really need to look at the statistics data to
see what's going on.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, john@arbash-meinel.com, fbsd@drivefaster.net
Subject: Re: slow joining very large table to smaller ones
In-Reply-To: <5708.1121383802@sss.pgh.pa.us>
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