Re: Updates on large tables are extremely slow - Mailing list pgsql-performance

From Yves Vindevogel
Subject Re: Updates on large tables are extremely slow
Date
Msg-id 93fcaa35413e2059526ab3aa562a17dd@implements.be
Whole thread Raw
In response to Re: Fwd: Updates on large tables are extremely slow  (Richard Huxton <dev@archonet.com>)
Responses Re: Updates on large tables are extremely slow  (Rod Taylor <pg@rbt.ca>)
Re: Updates on large tables are extremely slow  (Yves Vindevogel <yves.vindevogel@implements.be>)
Re: Updates on large tables are extremely slow  (Christopher Kings-Lynne <chriskl@familyhealth.com.au>)
List pgsql-performance
Ok, if all 21 are affected, I can understand the problem.

But allow me to say that this is a "functional error"


On 13 Jun 2005, at 18:02, Richard Huxton wrote:


<excerpt>Yves Vindevogel wrote:

<excerpt>I forgot cc

Begin forwarded message:

<excerpt>From: Yves Vindevogel <<yves.vindevogel@implements.be>

Date: Mon 13 Jun 2005 17:45:19 CEST

To: Tom Lane <<tgl@sss.pgh.pa.us>

Subject: Re: [PERFORM] Updates on large tables are extremely slow


Yes, but if I update one column, why should PG update 21 indexes ?

There's only one index affected !

</excerpt></excerpt>

No - all 21 are affected. MVCC creates a new row on disk.


--

  Richard Huxton

  Archonet Ltd



</excerpt>Met vriendelijke groeten,

Bien à vous,

Kind regards,


<bold>Yves Vindevogel</bold>

<bold>Implements</bold>

<smaller>

</smaller>Ok, if all 21 are affected, I can understand the problem.
But allow me to say that this is a "functional error"

On 13 Jun 2005, at 18:02, Richard Huxton wrote:

> Yves Vindevogel wrote:
>> I forgot cc
>> Begin forwarded message:
>>> From: Yves Vindevogel <yves.vindevogel@implements.be>
>>> Date: Mon 13 Jun 2005 17:45:19 CEST
>>> To: Tom Lane <tgl@sss.pgh.pa.us>
>>> Subject: Re: [PERFORM] Updates on large tables are extremely slow
>>>
>>> Yes, but if I update one column, why should PG update 21 indexes ?
>>> There's only one index affected !
>
> No - all 21 are affected. MVCC creates a new row on disk.
>
> --
>   Richard Huxton
>   Archonet Ltd
>
>
Met vriendelijke groeten,
Bien à vous,
Kind regards,

Yves Vindevogel
Implements

<smaller>


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

<italic><x-tad-smaller>

First they ignore you.  Then they laugh at you.  Then they fight you.
Then you win.

Mahatma Ghandi.</x-tad-smaller></italic></smaller>



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.

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