You didn't say what version of PostgreSQL you're trying.
I recall old version doesn't used index for backward pagination.
Oleg
On Mon, 23 May 2005, Yves Vindevogel wrote:
> I tried that, but
>
> create index ixTest on table1 (pages desc, documentname)
>
> gives me a syntax error
>
>
> On 23 May 2005, at 20:03, Steinar H. Gunderson wrote:
>
>> On Mon, May 23, 2005 at 07:41:19PM +0200, Yves Vindevogel wrote:
>>> 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.
>>
>> Make an index on "pages desc, documentname asc".
>>
>> /* Steinar */
>> --
>> Homepage: http://www.sesse.net/
>>
>> ---------------------------(end of broadcast)---------------------------
>> TIP 9: the planner will ignore your desire to choose an index scan if your
>> joining column's datatypes do not match
>>
>>
> Met vriendelijke groeten,
> Bien ? vous,
> Kind regards,
>
> Yves Vindevogel
> Implements
>
>
Regards,
Oleg
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Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
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