Re: Any better plan for this query?..

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От Alvaro Herrera
Тема Re: Any better plan for this query?..
Дата
Msg-id 20090507152632.GD3026@alvh.no-ip.org
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Ответ на Re: Any better plan for this query?..  (Dimitri <dimitrik.fr@gmail.com>)
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Dimitri escribió:

> As well when you look on profiling technology - all such kind of
> solutions are based on the system clock frequency and have their
> limits on time resolution. On my system this limit is 0.5ms, and it's
> too big comparing to the query execution time :-)
>
> So, what I've done - I changed little bit a reference key criteria from
> = '0000000001' to < '0000000051', so instead of 20 rows I have 1000
> rows on output now,

Another thing you can try is run the query several times (like 10000 or so).

--
Alvaro Herrera                                http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support

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