Subject: optimizer, view, union
From: Markus Bertheau <twanger@bluetwanger.de>
To: pgsql-sql@postgresql.org
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Date: Thu, 23 Jun 2005 19:31:57 +0200
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Hi,

Can pg transform

SELECT * FROM (
	SELECT 'foo' AS class, id FROM foo
	UNION ALL
	SELECT 'bar' AS class, id FROM bar
) AS a WHERE class =3D 'foo'

into

SELECT 'foo' AS class, * FROM foo?

The subselect is a view here, that's why I don't just use the second
query.

Markus

--=20
Markus Bertheau <twanger@bluetwanger.de>

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