Re: database performance and query performance question

Hannu Krosing kirjutas N, 22.01.2004 kell 22:46:
> Shea,Dan [CIS] kirjutas N, 22.01.2004 kell 22:35:
> > Something that I do not understand is why if you use a valid_time =
> > '2004-01-22 00:00:00' the query will use the index but if you do a
> > valid_time > '2004-01-22 00:00:00' it does not use the index?
>
> It probably can't tell if > is selective enough to justify using index.
>
> Together with "limit 10" it may be.
>
> You could try
>
> explain analyze select * from forecastelement where valid_time between
> '2004-01-22'::date and '2004-01-22'::date limit 10;

Sorry, that should have been:

between '2004-01-22'::date and '2004-01-23'::date

> to see if this is considered good enough.
>
> --------------
> Hannu
>
>
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