Friday, September 19, 2008

Re: [PERFORM] why does this use the wrong index?

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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