From: Tom Lane <tgl@sss.pgh.pa.us>
To: postgres@leangen.net
Cc: pgsql-performance@postgresql.org
Subject: Re: Delete operation VERY slow...
Date: Fri, 16 Jun 2006 09:30:32 -0400
Message-ID: <16186.1150464632@sss.pgh.pa.us> (raw)
In-Reply-To: <1150445542.4812.34.camel@sonoda.bioscene.co.jp>
References: <1150441126.4812.23.camel@sonoda.bioscene.co.jp>
<674d1f8a0606160022p1b042676gba28553bac5ab5ea@mail.gmail.com>
<1150445542.4812.34.camel@sonoda.bioscene.co.jp>
David Leangen <postgres@leangen.net> writes:
> The only inconvenience is that I need to remove all the foreign key
> constraints before truncating, then put them back after.
I was about to ask if you had any. Usually the reason for DELETE being
slow is that you have foreign key references to (not from) the table and
the referencing columns aren't indexed. This forces a seqscan search
of the referencing table for each row deleted :-(
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, postgres@leangen.net
Subject: Re: Delete operation VERY slow...
In-Reply-To: <16186.1150464632@sss.pgh.pa.us>
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