Hi, Thanks God, I have managed to shrink the roll back segment, though through some peculiar way. Instead of giving it directly the value 4M, I just shrinked it in steps, like The current size was 500M. alter rollback segment rbs25 shrink to 450M; alter rollback segment rbs25 shrink to 400M; ................ alter rollback segment rbs25 shrink to 10M; alter rollback segment rbs25 shrink to 4M; 4M is the optimal size of rbs I also executed the following statement just for check alter rollback segment rbs25 shrink to 3M; my concept was that Oracle won't allow me to shrink the rollback segment below optimal,but it allowed me to do so. Isnt it also peculiar? Please shed some light on these two things. regards, Fahd ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx put 'unsubscribe' in the subject line. -- Archives are at //www.freelists.org/archives/oracle-l/ FAQ is at //www.freelists.org/help/fom-serve/cache/1.html -----------------------------------------------------------------