From: John A Meinel <john@arbash-meinel.com>
To: 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 17:46:09 -0500
Message-ID: <42D6EB31.9040909@arbash-meinel.com> (raw)
In-Reply-To: <C3470621-9DB0-444A-BAD1-F9995E0142FB@drivefaster.net>
References: <46AF8F35-B735-4DFA-BA0A-AC82B5DA3CCE@drivefaster.net>
<42D687E5.7080202@arbash-meinel.com>
<C3470621-9DB0-444A-BAD1-F9995E0142FB@drivefaster.net>
Dan Harris wrote:
>
> On Jul 14, 2005, at 9:42 AM, John A Meinel wrote:
...
Did you try doing this to see how good the planners selectivity
estimates are?
>> Well, postgres is estimating around 500 rows each, is that way off? Try
>> just doing:
>> EXPLAIN ANALYZE SELECT incidentid FROM k_b WHERE id = 107;
>> EXPLAIN ANALYZE SELECT incidentid FROM k_r WHERE id = 94;
These should be fast queries.
John
=:->
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To: pgsql-performance@postgresql.org
Cc: john@arbash-meinel.com, fbsd@drivefaster.net
Subject: Re: slow joining very large table to smaller ones
In-Reply-To: <42D6EB31.9040909@arbash-meinel.com>
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