Yes, Mike, I analyzed the table and PK index on the two databases at the same way, it seems that there is something wrong with the PK index, the" select count(*) from table_name " query took 4 seconds, and only 335199 rows atcually. it use fast_full_index scan of the PK index, and I re-created the PK index, same thing. that's very bad.
it is Oracle 8.1.6 on win2000. thanks for reply. Kevin Wang ----- Original Message ----- To: "Multiple recipients of list ORACLE-L" <[EMAIL PROTECTED]> Sent: Wednesday, February 06, 2002 1:55 PM > Kevin, > > Have you analyzed the tables on both databases? Card is the CBO's estimate > of the number of rows it will process. > > Mike > > > > >From: "kevin wang" <[EMAIL PROTECTED]> > >Reply-To: [EMAIL PROTECTED] > >To: Multiple recipients of list ORACLE-L <[EMAIL PROTECTED]> > >Subject: question on EXPLAIN_PLAN > >Date: Wed, 06 Feb 2002 11:43:38 -0800 > > > > Hi, guys > > > > The problem belows is really make me confused and gave me big trouble, > >is there someone can give me some hlep? > > > > I have two databses, same version(oracle 8.1.6),same O/S(win2000), same > >schema structure, different data(but small difference of size). > > and even exactly same explain_plan of my sql query. > > But on one database, the cardinality of one PK index access upon one > >table is 27(cost=2,card=27,bytes=756) (table rows 263758) > > and the other is 11706!!!! (cost=3,card=11706,bytes=199002)( table rows > >351173). > > so, on one DB the sql query took 300ms, one the other, it took 5 > >seconds! > > > > Any advise is highly appreciated. > > > > thanks, > > > > Kevin Wang > > Database Administrator > > Vivonet Canada Inc. > > > > > > > > > _________________________________________________________________ > Chat with friends online, try MSN Messenger: http://messenger.msn.com > > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.com > -- > Author: Mike Killough > 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: kevin wang 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).
