From: Tom Lane <tgl@sss.pgh.pa.us>
To: ken@scottshill.com
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 16:07:29 -0500
Message-ID: <22658.1139951249@sss.pgh.pa.us> (raw)
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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
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To: pgsql-sql@postgresql.org
Cc: tgl@sss.pgh.pa.us, ken@scottshill.com, schabi@logix-tt.com
Subject: Re: Non Matching Records in Two Tables
In-Reply-To: <22658.1139951249@sss.pgh.pa.us>
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