There's a good document about this two interesting parameters: http://www.evdbt.com/SearchIntelligenceCBO.doc
and also see "asktom" http://asktom.oracle.com/pls/ask/f?p=4950:8:308736813964790489::NO::F4950_P8_DISPLAYID,F4950_P8_CRITERIA:6601251003901, ======= At 2003-06-16, 04:37:00 you wrote: ======= >The answer is found in the Jonathan Lewis book "Building Efficient Databases". >You should set OPTIMIZER_INDEX_COST_ADJ and OPTIMIZER_INDEX_CACHING. >Explanation: >It is realistic to expect a part of an index to be cached and it is also >realistic to expect the index access to be somewhat cheaper then the table >access. These two parameters give the same slant toward the index access path >and nested loops path as RBO. For the rest, buy Jonathan's book. > >On 2003.06.16 02:54, Hussain Ahmed Qadri wrote: >> Hi, >> We have two DBs, a production and a development, identical query was running >> very quickly on the Development and very slowly on the Production. Both have >> the similar structures, same number of indexes and everything. When I >> checked the explain plan, I found out that on the Production DB, it was >> doing a FTS on a couple of tables and was doing an Index scan on the >> Development server. The only difference was that the tables on the >> Production were ANALYZED. >> To confirm my theory, I analyzed the tables on Development and it started >> doing a FTS there as well hence slowing the query down. I know the >> optimizer, after analyzing, would have chosen the better path in its own >> sense but its not producing the desired result and it is taking ages now. >> is there any way to undo that? >> >> Regards, >> >> Hussain Ahmed Qadri >> DBA >> SKMCH&RC >> > >-- >Mladen Gogala >Oracle DBA >-- >Please see the official ORACLE-L FAQ: http://www.orafaq.net >-- >Author: Mladen Gogala > 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). > >. = = = = = = = = = = = = = = = = = = = = Best regards. Zhai Jingmin [EMAIL PROTECTED] 2003-06-16 -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Zhai Jingmin 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).