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From: Joshua Marsh <icub3d@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Terje Elde <terje@elde.net>
Cc: Jeff Davis <pgsql@j-davis.com>
Cc: pgsql-performance@postgresql.org
Cc: jim@nasby.net
Subject: Re: Performance With Joins on Large Tables
Date: Wed, 13 Sep 2006 15:18:49 -0600
Message-ID: <38242de90609131418j43d0dc88q3cb8a52dcceec287@mail.gmail.com> (raw)
In-Reply-To: <16645.1158181784@sss.pgh.pa.us>
References: <38242de90609121517y62517040v8622b9ae93cba23d@mail.gmail.com>
	<20060913064152.GC23173@nasby.net>
	<38242de90609130749u976295fwb10904ff4797b920@mail.gmail.com>
	<1158163655.29889.57.camel@dogma.v10.wvs>
	<38242de90609130919k33208204ka1006ff0ca25f75b@mail.gmail.com>
	<1158167054.29889.72.camel@dogma.v10.wvs>
	<45085F3A.1040108@elde.net>
	<38242de90609131327o68d2866fh92c12ddcf364aba7@mail.gmail.com>
	<16645.1158181784@sss.pgh.pa.us>

> Are the tables perhaps nearly in order by the dsiacctno fields?
> If that were the case, and the planner were missing it for some reason,
> these results would be plausible.
>
> BTW, what are you using for work_mem, and how does that compare to your
> available RAM?
>
>                        regards, tom lane
>

My assumption would be they are in exact order.  The text file I used
in the COPY statement had them in order, so if COPY preserves that in
the database, then it is in order.

The system has 8GB of ram and work_mem is set to 256MB.

I'll see if I can't make time to run the sort-seqscan method so we can
have an exact time to work with.

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