From: Tom Lane <tgl@sss.pgh.pa.us>
To: Karim Nassar <karim.nassar@NAU.EDU>
Cc: pgsql-performance@postgreSQL.org
Subject: Re: Delete query takes exorbitant amount of time
Date: Thu, 24 Mar 2005 20:48:38 -0500
Message-ID: <3750.1111715318@sss.pgh.pa.us> (raw)
In-Reply-To: <1111715131.9085.174.camel@k2.cet.nau.edu>
References: <1111709457.9085.127.camel@k2.cet.nau.edu>
<2630.1111711927@sss.pgh.pa.us>
<1111715131.9085.174.camel@k2.cet.nau.edu>
Karim Nassar <karim.nassar@NAU.EDU> writes:
>> Look at what your triggers are doing. My private bet is that you have
>> unindexed foreign keys referencing this table, and so each deletion
>> forces a seqscan of some other, evidently very large, table(s).
> Almost. I have a large table (6.3 million rows) with a foreign key
> reference to this one (which has 749 rows), however it is indexed.
In that case there's a datatype mismatch between the referencing and
referenced columns, which prevents the index from being used for the
FK check.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, karim.nassar@NAU.EDU
Subject: Re: Delete query takes exorbitant amount of time
In-Reply-To: <3750.1111715318@sss.pgh.pa.us>
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