Sergei, My first guess will be you are using a loop and you are committing intermittently. If so, then the rollback segment used is not RBIG20. Any time a commit or rollback occurs, you are starting new transaction and hence a new rollback segment may be allocated; in this case it's R27.
The second guess is you are using some autonomous transaction in a trigger on the table. Third guess (although not likely) is you are using a construct like update TAB1 set COL1 = function(COL1) where COL1 = <some value> If so, then you rollback segment has to be much bigger to make the read consistency view possible. HTH Arup Nanda ----- Original Message ----- To: "Multiple recipients of list ORACLE-L" <[EMAIL PROTECTED]> Sent: Friday, January 03, 2003 2:49 PM > I am running 8.1.6 on solaris 2.8. > > Before running a large update, I tried to set a specific rollback > segment by: > Set transaction use rollback segment RBIG20; > > The transaction runs for a while and fails with: > > ORA-01555: snapshot too old: rollback segment number 29 with name "R27" > too > Small > > Any idea? > > Thank you > > Sergei > > > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.net > -- > Author: Sergei > 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). > -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Arup Nanda 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).