Skip navigation.

ORA-1555 and SQL Tuning

Often DBAs may look to tuning the UNDO* parameters as a solution towards the infamous "ORA-1555 snapshot too old" error. In most cases, before looking to tune UNDO* parameters, the best solution is to tune the query that's running into the ORA-1555 error so the query will not error out with ORA-1555 to begin with!

Hope this helps a fellow DBA or two trying to resolve the ORA-1555(s) !