Tim Gorman wrote a good paper about using these parameters: http://www.evdbt.com/SearchIntelligenceCBO.doc
Shaw John-P55297 wrote: > > have you tried adjusting optimzer_index_caching and > optimizer_index_cost_adj? > > -----Original Message----- > Sent: Thursday, March 07, 2002 1:23 PM > To: Multiple recipients of list ORACLE-L > > I work in a dev shop - most of the sql is canned and pretty basic. We've > been running CBO in all of our dev environments, but we have a few long txns > that just take forever. At the request of some savvy developers, I turned > on RBO, and it brought down execution times dramatically. > > I've been analyzing affected tables often (we do a lot of bulk load/unload > for testing), and have played with partitioning and clustering, particularly > on one table that's just a dog. CBO will always do a FTS where RBO uses the > PK to retrieve data. > > Where to go next? I've been unable to alter the costs dramatically enough > to make any real difference in execution time. > > thx > > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.com > -- > Author: Magaliff, Bill > INET: [EMAIL PROTECTED] > > Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 > San Diego, California -- Public Internet access / Mailing Lists > -------------------------------------------------------------------- > 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). > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.com > -- > Author: Shaw John-P55297 > INET: [EMAIL PROTECTED] > > Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 > San Diego, California -- Public Internet access / Mailing Lists > -------------------------------------------------------------------- > 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). -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Suzy Vordos INET: [EMAIL PROTECTED] Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- 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).
