Jeff Moden (7/22/2010)
Maybe that's true in Oracle but it's not true in SQL Server. Oracle is mostly rule based and SQL Server is cost based.
I'm glad you commented this article, Jeff. Great discussion.
A minor note on the Oracle thing: it used to be completely rule-based, but now it's entirely cost-based. Starting from version 10g the rule-based optimizer is no longer available.
-- Gianluca Sartori