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

On Thu, 27 Jan 2005, PFC wrote:

>
>> Thats a really good idea, just store a list of the sorted ids in the
>> temp table - small amount of data for insert... I like it!
>>
>> Alex Turner
>> NetEconomist
>
>     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.

> you'll have to trick the thing by generating a query with IN, or joining
> against a SRF returning the elements of the array one by one, which might be
> better.
>
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     Regards,
         Oleg
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Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
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