From: Ken Hill <ken@scottshill.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Markus Schaber <schabi@logix-tt.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: Non Matching Records in Two Tables
Date: Tue, 14 Feb 2006 13:25:36 -0800
Message-ID: <1139952337.3083.68.camel@localhost.localdomain> (raw)
In-Reply-To: <22658.1139951249@sss.pgh.pa.us>
References: <1139433024.2044.48.camel@localhost.localdomain>
<43EA6333.7050604@logix-tt.com>
<1139950507.3083.64.camel@localhost.localdomain>
<22658.1139951249@sss.pgh.pa.us>
On Tue, 2006-02-14 at 16:07 -0500, Tom Lane wrote:
> Ken Hill <ken@scottshill.com> writes:
> > Seq Scan on ncccr10 (cost=0.00..20417160510.08 rows=305782 width=104)
> > Filter: (NOT (subplan))
> > SubPlan
> > -> Seq Scan on ncccr9 (cost=0.00..65533.71 rows=494471 width=104)
> > (4 rows)
>
> > Any ideas why it is so slow?
>
> "NOT (subplan)" is horrendous (and the system knows it, note the huge
> cost estimate). Try increasing work_mem enough so you get a hashed
> subplan instead.
>
> regards, tom lane
How do I ncrease work_mem?
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To: pgsql-sql@postgresql.org
Cc: ken@scottshill.com, tgl@sss.pgh.pa.us, schabi@logix-tt.com
Subject: Re: Non Matching Records in Two Tables
In-Reply-To: <1139952337.3083.68.camel@localhost.localdomain>
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