Where current of statement is not updating correct row oracle

That user is updating\inserting\deleting a lot of database records without committing.Oracle clears out any unneeded transactions in the rollback segment but eventually it fills up and the error occurs. User B logs into the data base and is updating\inserting\deleting a lot of database records, but is committing every 100 records.

where current of statement is not updating correct row oracle-27

I've been dealing with this error off and on for the last 3 years and I just wanted to verify that my understanding of its cause is accurate.

Cause 1) There is only one user logged into the database.

MAY cause A to experience an ORA-1555 if A is performing a long running query against the object(s) B is modifying. It is when it is overwritten that user A will get the ORA-1555.

An ORA-1555 is never about running out of rollback.

These rollback segments COULD grow to 100meg each if we let them (in this example) however, they will NEVER grow unless you get a big transaction.

If your database does lots of little transactions, the RBS will never grow on their own. Now, someone needs to run a query that will take 5 minutes. What will be the condition at which the rollback segment wraps to extent 1.They'll have small rollback segments that could grow if they needed (and will shrink using OPTIMAL).So, they'll start with say 10 or so 1meg rollback segments.if you are in extent N and N 1 is being used still (or with AUM N 1 contains information that cannot yet be overwritten because of the undo_retention), we'll allocate a new extent and stick it in there.I still am a bit unclear what makes the RBS advance.If the RBS has to extend, it will not use a extent that has an active TX but link in a new extent.

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