Re: very slow updates in 8.3?

From: "Richard Broersma" <richard(dot)broersma(at)gmail(dot)com>
To: anton(dot)andreev(at)fmi(dot)uni-sofia(dot)bg
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: very slow updates in 8.3?
Date: 2008-04-19 13:21:06
Message-ID: 396486430804190621o5cecbb3ar61a6d05b6378e14c@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

On Sat, Apr 19, 2008 at 1:33 AM, Anton Andreev <fn30762(at)fmi(dot)uni-sofia(dot)bg> wrote:
> update table1 set params_count=0;
> it takes too long to complete: 11000 rows - 100 s.
> Postgresql 8.3 configuration on Turion 64 with 1.4 Gb RAM, Windows XP
> Which compiler is used to build Postgresql on Windows? Is it 9?

Does this table have alot of indexs, or trigger function for deletes?

Remember that in postgresql, an update is really a delete and an
insert since postgreSQL uses the MVCC model. So you are actually
doing twice the work.

To start, could you post the EXPLAIN ANALYZE for this query?

Also, if you are going to run this query alot, you might want to alter
your FILLFACTOR for you table and associated index to 50%.

ALTER TABLE yourtable SET ( FILLFACTOR = 50 );
ALTER INDEX yourindex1 SET ( FILLFACTOR = 50);

--
Regards,
Richard Broersma Jr.

In response to

Browse pgsql-general by date

  From Date Subject
Next Message x asasaxax 2008-04-19 14:47:19 SQL error
Previous Message David Fetter 2008-04-19 11:18:08 Re: I need to ecrypt one column to an output file