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Re: why does explain tell me I'm using a seq scan? - Mailing list pgsql-general

From Rod Taylor
Subject Re: why does explain tell me I'm using a seq scan?
Date
Msg-id 1068250763.61532.6.camel@jester
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In response to why does explain tell me I'm using a seq scan?  (Mark Harrison <mh@pixar.com>)
List pgsql-general
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On Fri, 2003-11-07 at 19:11, Mark Harrison wrote:
> I have indexed two columns in a table.  Can somebody explain to me why
> the first query below uses an Index Scan while the second uses a Seq
> Scan?

The first expects to find a single row, the second expects to find 17000
rows, a significant portion of the table where an index scan would be a
loss based on current tuning parameters.

--
Rod Taylor <pg [at] rbt [dot] ca>

Build A Brighter Lamp :: Linux Apache {middleware} PostgreSQL

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