ORA-01555 Snapshot too old
March 16th, 2009 Posted in DBA Thoughts, Oracle Tip
Do you ever see the Oracle error “ORA-01555 Snapshot too old (Rollback has been overwritten)”? It is a pretty common error, but one I don’t see much anymore.
ORA-01555 error means the rollback segment that your long running query needed has been overwritten. Today I was helping out a friend who has been getting this error trying to execute a delete command. I directed him to a pretty good article on the subject over at orafaq.com. Take a look at the article, it has a lot of good information on properly dealing with the UNDO tablespace.
