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Re: why does this use the wrong index? - Mailing list pgsql-performance

From Jeff Davis
Subject Re: why does this use the wrong index?
Date
Msg-id 1221849804.6194.297.camel@dell.linuxdev.us.dell.com
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In response to Re: why does this use the wrong index?  (Jeff Davis <pgsql@j-davis.com>)
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On Fri, 2008-09-19 at 11:25 -0700, Jeff Davis wrote:
> What's the n_distinct for start_time?

Actually, I take that back. Apparently, PostgreSQL can't change "x
BETWEEN y AND y" into "x=y", so PostgreSQL can't use n_distinct at all.

That's your problem. If it's one day only, change it to equality and it
should be fine.

Regards,
    Jeff Davis

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