Re: OCP Question (Perf Tuning)

I see you're running on Oracle 9 there, and that can make a big difference. After posting my hypothesis, I created a test case, which behaved as I had predicted - but the behaviour changed in Oracle 9, and I had to do some tweaking.

Turns out my test case highlighted what looks like a but in the SORT costing in Oracle 8 for a sort/merge join. The Oracle 9 costing is better, so Oracle 9 didn't switch to an NL when Oracle 8 did.

Regards

Jonathan Lewis
http://www.jlcomp.demon.co.uk

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• Original Message ----- To: "Multiple recipients of list ORACLE-L" <ORACLE-L_at_fatcity.com> Sent: Tuesday, January 06, 2004 9:14 PM

> Jonathan, you're right. Interesting thing is that bitmap indexes, which
were made for
> DW processing and not for OLTP will also be considered for NL context in
First_Rows mode.
> Here is the proof, which also proves that I'm a lousy typist:
>

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