Quote Originally Posted by tmgsam View Post
If it is from data segment we wont get ora 0155 error beacuse new data is available there but if it from rbs then we will get.Please clear ..
Well as it seems from PAVB's 2nd last reply, the oracle server will direct the new transaction towards data block's header that will state dat the transaction is uncommitted bcos of delayed cleanout, so the transaction will now refer to rollback segment whose header wud contain the information dat the earlier transaction dat created this rollback segment is now committed. So the available data block in buffer cache is marked as it is of committed transaction and is the only candidate for data retrieval or DML.
But if rollback segment is not there, then all this will not happen and you will receive the error "SNAPSHOT TOO OLD"