Interesting point . . . but the flip side of your argument is that by putting hints in we, as the vendor, while not "requiring" you to use CBO (since RBO will just ignore the hints) are saying, 'Hey, you had BETTER use CBO if you want this thing to work the way we've designed it'
interesting to continue this discussion thread, although it's separate from the tuning issue I need to look at -biill -----Original Message----- Sent: Thu, March 07, 2002 2:44 PM To: Multiple recipients of list ORACLE-L Bill - Are you saying that you switched to RBO for everything? I thought the better procedure would be to remain CBO and put hints into individual SQL queries. Is this a possibility in your environment? You mention that you are a development shop. Does this mean that you create software and sell it to others? Personally, I wouldn't be pleased if my company purchased some software and found it required me to switch my database to RBO. Dennis Williams DBA Lifetouch, Inc. [EMAIL PROTECTED] -----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: DENNIS WILLIAMS 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: 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).
