explanation: what i've found is cost has absolutely no bearing on anything, a relatively useless number.
joe Baylis, John wrote: > I have a table of 500,000 records that is analyzed and contains > several indexes that are analyzed. > > Can someone explain to me why the cost without a hint is much lower > than the cost with a hint? > > Using a hint is 10 times faster than without a hint even though the > cost is much higher. > > Since this is a third party app, I cannot add hints. What aoptions do > I have? > > > select /*+ Index("ICMSSHDR" XSKSHDRS181M1) Use this index > XSKSHDRS181M1 */ > PKTS_ICMSSHDR from ICMSSHDR > where (FK_IX_ICMSSHDR_DELV='x' and (SHDR_DELV_WHSE_CODE<'86')); > > Execution Plan > ---------------------------------------------------------- > 0 SELECT STATEMENT Optimizer=CHOOSE (Cost=213529 Card=228346 > Bytes=12102338) > 1 0 TABLE ACCESS (BY INDEX ROWID) OF 'ICMSSHDR' (Cost=213529 > Card=228346 Bytes=12102338) > 2 1 INDEX (RANGE SCAN) OF 'XSKSHDRS181M1' (NON-UNIQUE) > (Cost=2346 Card=228346) > > > select PKTS_ICMSSHDR from ICMSSHDR > where (FK_IX_ICMSSHDR_DELV='x' and (SHDR_DELV_WHSE_CODE<'86')); > > > Execution Plan > ---------------------------------------------------------- > 0 SELECT STATEMENT Optimizer=CHOOSE (Cost=3526 Card=228346 > Bytes=12102338) > 1 0 TABLE ACCESS (FULL) OF 'ICMSSHDR' (Cost=3526 Card=228346 > Bytes=12102338) > > > Thanks > > *John Baylis* > D atabase Administrator > Canadian Forest Products Ltd. > Vancouver B.C. Canada > > (604) 697-6476 (Office) > (604) 313-6054 (Cell) > > -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Joseph S Testa 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).