Begin forwarded message:
<excerpt><bold><color><param>0000,0000,0000</param>From:
</color></bold>Yves Vindevogel <<yves.vindevogel@implements.be>
<bold><color><param>0000,0000,0000</param>Date: </color></bold>Mon 23
May 2005 19:23:16 CEST
<bold><color><param>0000,0000,0000</param>To:
</color></bold>pgsql-performance-owner@postgresql.org
<bold><color><param>0000,0000,0000</param>Subject: </color>Index on
table when using DESC clause
</bold>
Hi,
I have a table with multiple fields. Two of them are documentname and
pages
I have indexes on documentname and on pages, and one extra on
documentname + pages
However, when I query my db using for instance order by pages,
documentname, it is very fast.
If I use order by pages desc, documentname, it is not fast at all,
like it is not using the index properly at all.
How can I avoid this ?
Met vriendelijke groeten,
Bien à vous,
Kind regards,
<bold>Yves Vindevogel</bold>
<bold>Implements</bold>
<smaller>
</smaller></excerpt>
Begin forwarded message:
> From: Yves Vindevogel <yves.vindevogel@implements.be>
> Date: Mon 23 May 2005 19:23:16 CEST
> To: pgsql-performance-owner@postgresql.org
> Subject: Index on table when using DESC clause
>
> Hi,
>
> I have a table with multiple fields. Two of them are documentname and
> pages
> I have indexes on documentname and on pages, and one extra on
> documentname + pages
>
> However, when I query my db using for instance order by pages,
> documentname, it is very fast.
> If I use order by pages desc, documentname, it is not fast at all,
> like it is not using the index properly at all.
>
> How can I avoid this ?
>
> Met vriendelijke groeten,
> Bien à vous,
> Kind regards,
>
> Yves Vindevogel
> Implements
>
<excerpt><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></excerpt>Met vriendelijke groeten,
Bien à vous,
Kind regards,
<bold>Yves Vindevogel</bold>
<bold>Implements</bold>
<smaller>
</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.
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.
