David, I would probably not try to tune a query to make it use an index but tune a query to make it run faster - I have had recently a nice example, a join between a 500K row table and two 2K row tables (returning about 2K rows too) was running faster with FTS (followed by hash joins) on _ALL_ tables than when using the primary key of the big table (it was about twice as fast). Try avoiding prejudices...
Otherwise, no, the calculation cannot cause the problem in that case. I would also get all columns in the SELECT list from the same table, just in case. HTH, SF >----- ------- Original Message ------- ----- >From: David Wagoner <[EMAIL PROTECTED]> >To: Multiple recipients of list ORACLE-L ><[EMAIL PROTECTED]> >Sent: Mon, 27 Oct 2003 07:34:26 > >I'm trying to tune the following query to use an >index on the FILE_DTS >column, rather than a FTS on the CLASS_CONFIG table >(~350,000 rows). > >SELECT a2.class_config_id, a1.schedule_name >FROM class_config a2, class_schedule a1 >WHERE a2.class_config_id = a1.class_config_id >AND to_date(a2.file_dts, 'mmddyyhh24miss') > >SYSDATE - 35 > > >I created a function-based index on FILE_DTS, like >this: > >CREATE INDEX CLASS_CONFIG_FILE_DTS_FX_IDX ON >CLASS_CONFIG to_date(file_dts, >'mmddyyhh24miss') > >and analyzed the table, but the explain plan still >shows a FTS. I can >change the query to something simpler and get it to >use the new index, but I >assume the calculation (> SYSDATE - 35) is causing >the problem. Any >suggestions? > > >Best regards, > >David B. Wagoner >Database Administrator >Arsenal Digital Solutions >Web: http://www.arsenaldigital.com > > <<...OLE_Obj...>> > > >The contents of this e-mail message may be >privileged and/or confidential. >If you are not the intended recipient, any review, >dissemination, copying, >distribution or other use of the contents of this >message or any attachment >by you is strictly prohibited. If you receive this >communication in error, >please notify us immediately by return e-mail or by >telephone >(919-466-6700), and please delete this message and >all attachments from your >system. >Thank you. > Regards, Stephane Faroult Oriole -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Stephane Faroult 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).
