altering RBS datafiles and rollback segments to avoid ORA-1555

[beksalur]

now,we have two raw datafile each one 3 GB in RBS Tablespace and in it there is 30 rollback segments with the following parameters;
initial=10 MB
next=10 MB
optimal=20 MB
min. number=2
max. number=505
First,We want to expand the two datafiles to 10 GB and then
increase rollback segment storage parameter and not to use optimal option to avoid ORA-1555 errors. what do you think about it, how can i do it?(exact sql syntax pls.)and can i do it when the db is online?

 

[jocave]

Why would you be eliminating the optimal option? In most situations I've seen, I'd be for increasing that value, not decreasing it.

What sort of activity is your database doing?
Are you sure you understand why the ORA-01555 errors are happening?

Justin

 

[beksalur]

we use BaanERP as application server,and in it there are transactions even mining 2 GB of datasets.du to our RBS size is small,we are often get ora-1555 errors.that is why we want to expand RBS tablespace.
our oracle support center adviced us not to use optimal option at rollback segments.

Thanks.

 

[sem]

Give a glance at thread186-628107 and probably you change your decision to resize RBs

Regards, Dima