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Home -> Community -> Usenet -> c.d.o.server -> Re: How hints affect the CBO?
Hints are mandatory if valid AND if there is no way of avoiding the hint.
Think of Oracle as a five-year-old genius, and imagine this conversation:
Parent (in tones of wrath)
"I told you not to take the biscuits"
Child (in tones of injured innocence)
"I didn't take the biscuits - Jimmy took the biscuits and gave them to me."
Oracle has many optimisation options
built in that may allow it to find a route
that __appears__ to ignore your hint.
-- Jonathan Lewis http://www.jlcomp.demon.co.uk Next Seminars UK July / Sept Australia July / August Malaysia September USA (MI) November http://www.jlcomp.demon.co.uk/seminar.html Vladimir M. Zakharychev wrote in message ...Received on Sat Jun 29 2002 - 04:01:47 CDT
>
>At least I am no longer speculating about true CBO behavior with regard to
>hints and know for sure they are mandatory if valid.
>
>--
>Vladimir Zakharychev (bob_at_dpsp-yes.com)
http://www.dpsp-yes.com