Date: Mon, 17 May 2010 14:28:16 +0200
From: "A. Kretschmer" <andreas.kretschmer@schollglas.com>
To: pgsql-performance@postgresql.org
Subject: Re: Slow Bulk Delete
Message-ID: <20100517122816.GA31501@a-kretschmer.de>
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	<op.vcug7tj0eorkce@immo.peufeu.com>
	<AANLkTinEPzUlYprV0Cm5rvFPl5AQg08483pxAgSIxAnJ@mail.gmail.com>
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In response to Jon Nelson :
> On Mon, May 17, 2010 at 5:10 AM, Pierre C <lists@peufeu.com> wrote:
> > - or use a JOIN delete with a virtual VALUES table
> > - or fill a temp table with ids and use a JOIN DELETE
> 
> What is a virtual VALUES table? Can you give me an example of using a
> virtual table with selects, joins, and also deletes?

Something like this:

test=# select * from foo;
 c1
----
  1
  2
  3
  4
(4 rows)

test=*# delete from foo using (values (1),(2) ) as bla where foo.c1=bla.column1;
DELETE 2
test=*# select * from foo;
 c1
----
  3
  4
(2 rows)


values (1), (2) as bla   -> returns a 'virtual table' bla with one
column column1.


Andreas
-- 
Andreas Kretschmer
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