From: Yves Vindevogel <yves.vindevogel@implements.be>
To: pgsql-performance@postgresql.org
Subject: Re: View not using index
Date: Mon, 13 Jun 2005 09:18:50 +0200
Message-ID: <ea465cec82454372ead9c8a92a795d71@implements.be> (raw)
In-Reply-To: <200506131705.35852.mr-russ@pws.com.au>
References: <9e1745a6fe1ae29c6f1c824128871d36@implements.be>
<200506131705.35852.mr-russ@pws.com.au>
rvponp=# explain select * from vw_document_pagesperjob ;
QUERY PLAN
------------------------------------------------------------------------
----------------
Subquery Scan vw_document_pagesperjob (cost=82796.59..90149.20
rows=588209 width=706)
-> Sort (cost=82796.59..84267.11 rows=588209 width=74)
Sort Key: tblprintjobs.descpages, tblprintjobs.documentname
-> Seq Scan on tblprintjobs (cost=0.00..26428.61 rows=588209
width=74)
(4 rows)
rvponp=# explain select * from vw_document_pagesperjob limit 10 ;
QUERY PLAN
------------------------------------------------------------------------
----------------------
Limit (cost=82796.59..82796.72 rows=10 width=706)
-> Subquery Scan vw_document_pagesperjob (cost=82796.59..90149.20
rows=588209 width=706)
-> Sort (cost=82796.59..84267.11 rows=588209 width=74)
Sort Key: tblprintjobs.descpages,
tblprintjobs.documentname
-> Seq Scan on tblprintjobs (cost=0.00..26428.61
rows=588209 width=74)
(5 rows)
rvponp=# explain select documentname, eventdate, eventtime, loginuser,
pages from tblPrintjobs order
by descpages, documentname ;
QUERY PLAN
------------------------------------------------------------------------
----
Sort (cost=81326.07..82796.59 rows=588209 width=74)
Sort Key: descpages, documentname
-> Seq Scan on tblprintjobs (cost=0.00..24958.09 rows=588209
width=74)
(3 rows)
rvponp=# explain select documentname, eventdate, eventtime, loginuser,
pages from tblPrintjobs order
by descpages, documentname limit 10 ;
QUERY PLAN
------------------------------------------------------------------------
-------------------------------------
Limit (cost=0.00..33.14 rows=10 width=74)
-> Index Scan using ixprintjobspagesperjob on tblprintjobs
(cost=0.00..1949116.68 rows=588209 width=74)
(2 rows)
create or replace view vw_document_pagesperjob as
select documentname, eventdate, eventtime, loginuser,
fnFormatInt(pages) as pages
from tblPrintjobs
order by descpages, documentname ;
On 13 Jun 2005, at 09:05, Russell Smith wrote:
> On Mon, 13 Jun 2005 04:54 pm, Yves Vindevogel wrote:
>> Still, when I use explain, pg says it will first sort my tables
>> instead
>> of using my index
>> How is that possible ?
>
> Can we see the output of the explain analyze?
> The definition of the view?
>
> Regards
>
> Russell Smith
>
>
Met vriendelijke groeten,
Bien à vous,
Kind regards,
Yves Vindevogel
Implements
Mail: yves.vindevogel@implements.be - Mobile: +32 (478) 80 82 91
Kempische Steenweg 206 - 3500 Hasselt - Tel-Fax: +32 (11) 43 55 76
Web: http://www.implements.be
First they ignore you. Then they laugh at you. Then they fight you.
Then you win.
Mahatma Ghandi.
Attachments:Pasted Graphic 2.tiff (image/tiff, 5.6K) downloadview image
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-performance@postgresql.org
Cc: yves.vindevogel@implements.be
Subject: Re: View not using index
In-Reply-To: <ea465cec82454372ead9c8a92a795d71@implements.be>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox