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Re: Why does a simple query not use an obvious index? - Mailing list pgsql-performance

From Greg Stark
Subject Re: Why does a simple query not use an obvious index?
Date
Msg-id 87k6vgiqge.fsf@stark.xeocode.com
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In response to Re: Why does a simple query not use an obvious index?  (Guy Thornley <guy@esphion.com>)
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Guy Thornley <guy@esphion.com> writes:

>             "stats__ends_at" btree (stats__ends_at("at", resolution, "values"))

Postgres 7.4 doesn't have any stats on functional indexes. So it's back to
just guessing at the selectivity of this. 8.0 does gather stats for functional
indexes so it should be better off.

--
greg

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