Re: Index not used with or condition

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От Antony Paul
Тема Re: Index not used with or condition
Дата
Msg-id 2989532e05020703584989cd15@mail.gmail.com
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Ответ на Re: Index not used with or condition  (Jan Poslusny <pajout@gingerall.cz>)
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I ran analyze; several times.

rgds
Antony Paul


On Mon, 07 Feb 2005 12:53:30 +0100, Jan Poslusny <pajout@gingerall.cz> wrote:
> It depends on many circumstances, but, at first, simple question: Did
> you run vacuum analyze?
> I am satisfied with functional indexes - it works in my pg 7.4.x.
>
> Antony Paul wrote:
>
> >On more investigation I found that index scan is not used if the query
> >have a function in it like lower() and an index exist for lower()
> >column.
> >
> >rgds
> >Antony Paul
> >
> >
> >On Mon, 7 Feb 2005 14:37:15 +0530, Antony Paul <antonypaul24@gmail.com> wrote:
> >
> >
> >>Hi all,
> >>    I am facing a strange problem when I run EXPLAIN against a table
> >>having more than 100000 records. The query have lot of OR conditions
> >>and when parts of the query is removed it is using index. To analyse
> >>it I created a table with a single column, inserted 100000
> >>records(random number) in it created index and run a query which
> >>returns 1 record which have no or condition and it was using index.  I
> >>added an OR conditon and is using sequential scan. I set the
> >>enable_seqscan to off. I ran the tests again and is using index scan.
> >>   So which one I have to use. Is this any bug in Explain.
> >>
> >>rgds
> >>Antony Paul.
> >>
> >>
> >>
> >
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> >
> >
>

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