Tom,
Back in the 7.0 days,
WHERE EXISTS (SELECT * FROM a WHERE condition)
was significantly slower on broad tables than
WHERE EXISTS (SELECT small_col FROM a WHERE condition)
Is this still true, or something that's been fixed in the last 3 versions?
Joe Celko is making fun of me because Oracle doesn't have this performance
issue.
--
Josh Berkus
Aglio Database Solutions
San Francisco