oracle7 optimizer

To oacle7 users:

what is the difference between oracle v6 optimizer and oracle7's one?

  The feature summary of oracle7 mentioned that its optimizer is   cost-based and the evaluation can be based on statistics about table's   data and storage characteristics and is independent of query syntax, etc.

what is the impact on the current queries implemented for V6?

will the query path ranking policy still be applicable/valuable to the queries?

thanks.

-- 
David So			Internet: david.so_at_Software.Mitel.COM
Mitel Corp.
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