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Home -> Community -> Mailing Lists -> Oracle-L -> consistency in cost?
I am working with an 8.1.6 database on Solaris 2.6 and I am wondering if there is any consistency in the optimizer. We have two nearly identical databases (one a clone from two weeks ago). A five table join has nearly the identical execution plan on the two databases. The difference is in the access method of the fourth table in the join; in one case it is accessed by a FTS and in the other, by Index. This difference has a large effect on performance. Statistics are nearly identical for this table in both databases (I looked at dba_tables, dba_indexes, dba_col_tables). Also, the init.ora is the same. When I changed the optimizer_mode to rule and added a 'choose' hint to the query, the execution plan was different again. I will look into this a bit further and post my results. Just wondering about other's experiences. Thanks.
Henry
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Author: Henry Poras
INET: Henry.Poras_at_ctp.com
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: ListGuru_at_fatcity.com (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). Received on Mon May 07 2001 - 23:08:45 CDT
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