That parameter does not make CBO comes up with any smarter plans - just more likely to choose NLJ whether its better or not. HJ can outperform all other joins in a lot of cases if you maintain statistics judiciously, including the appropriate use of histograms.
>>> [EMAIL PROTECTED] 11/21/02 12:24a.m. >>> One quick hack is to set the "optimizer_..." params to make indexes look super-wonderful, which then gives you a rule-based "look and feel" with hopefully a little smarter selection of indexes as a bonus hth connor --- VIVEK_SHARMA <[EMAIL PROTECTED]> wrote: > > Consider using OUTLINES for Fixed Execution plans > especially for Batch Queries > > This will prevent a Sudden Increment in Processing > Time due to Optimizer choosing NON-Optimal paths > > > -----Original Message----- > Sent: Wednesday, November 20, 2002 3:20 AM > To: Multiple recipients of list ORACLE-L > > > We will be in the same process soon. > We'll have to consolidate over 100 instances to > something between 40-60 instances and switch from > RBO > to CBO. > > Any tips are welcome. > > > --- Steve McClure <[EMAIL PROTECTED]> a �crit : > > > I am just starting to look at converting to the cost > > based optimizer, and am > > hoping a few of you can share insights from having > > done so in the past. Our > > application is an oltp system developed on 7.3.4. > > > We made liberal use of > > +0 and other RBO "hints", and I am wondering if > > these are going to cause us > > troubles when switching to CBO. > > > > We have been on 8i since April of this year, and > I > > am just now starting to > > gather information on the inner workings of the > CBO. > > I know it is where I > > want to be, I am just looking to see how > > painful/painless the transition > > will be. > > > > Steve McClure > > -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Binley Lim INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
