From: Junaili Lie <junaili@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-performance@postgresql.org
Subject: Re: slow deletes on pgsql 7.4
Date: Tue, 25 Apr 2006 17:14:56 -0700
Message-ID: <8d04ce990604251714g1f5d99bbn172ec554a49c8374@mail.gmail.com> (raw)
In-Reply-To: <9147.1146006558@sss.pgh.pa.us>
References: <8d04ce990604251441ya85c42evb47946272536cabe@mail.gmail.com>
<9147.1146006558@sss.pgh.pa.us>
hi,
Thanks for the answer.
I have double checked that all the foreign key that are referencing "id" on
scenario are indexed.
I have even vacuum analyze scenario table and all the tables that referenced
this table.
Something that is interesting is that: it only happens for a certain values.
ie. delete from scenario where id='1023' is very fast, but delete from
scenario where id='1099' is running forever.
Any ideas?
J
On 4/25/06, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>
> "Junaili Lie" <junaili@gmail.com> writes:
> > we encounter issues when deleting from a table based on id (primary
> key). O=
> > n
> > certain 'id', it took forever to delete and the i/o is 100% busy.
>
> Almost always, if delete is slow when selecting the same rows is fast,
> it's because you've got a trigger performance problem --- most commonly,
> there are foreign keys referencing this table from other tables and you
> don't have the referencing columns indexed.
>
> regards, tom lane
>
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Cc: junaili@gmail.com, tgl@sss.pgh.pa.us
Subject: Re: slow deletes on pgsql 7.4
In-Reply-To: <8d04ce990604251714g1f5d99bbn172ec554a49c8374@mail.gmail.com>
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