Re: [SQL] OFFSET impact on Performance???

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От Oleg Bartunov
Тема Re: [SQL] OFFSET impact on Performance???
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Msg-id Pine.GSO.4.62.0501271415370.6701@ra.sai.msu.su
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Ответ на Re: [SQL] OFFSET impact on Performance???  (PFC <lists@boutiquenumerique.com>)
Ответы Re: [SQL] OFFSET impact on Performance???
Re: [SQL] OFFSET impact on Performance???
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On Thu, 27 Jan 2005, PFC wrote:

>
>>>     The best part is that you can skip the LIMIT/OFFSET entirely if you
>>> put page numbers in your cache table while inserting into it, via a
>>> temporary sequence or something. Retrieving the results will then be very
>>> fast, but beware that SELECT * FROM table WHERE id =ANY( array ) won't use
>>> an index, so
>>
>> contrib/intarray provides index access to such queries.
>
>     Can you provide an example of such a query ? I've looked at the
> operators for intarray without finding it.

for example,
http://www.sai.msu.su/~megera/postgres/gist/code/7.3/README.intarray
see OPERATIONS and EXAMPLE USAGE:

SELECT * FROM table WHERE id && int[]


>     Thanks.
>

     Regards,
         Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83

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