00390-00399: Redo Log Files

Cause:	An attempt to switch to a new online log for the redo thread failed because no reusable log could be found. This log is being cleared and will be useable when the clearing completes. The command that began the clearing may have terminated without completing the clearing.

Action:	If the clear command is still executing, then wait for its completion. If it terminated, then re-enter the clear command or drop the log.

ORA-00391 all threads must switch to new log format at the same time

Cause:	An attempt to switch the current log of a single thread is not allowed because the compatibility requirements force a new log format version number. When changing log formats, all threads must switch to the new format at the same time.

Action:	Open the database to cause the coordinated log switch. If that is not possible, then return to the same software version and compatibility setting last used to open the database.

ORA-00392 log name of thread num is being cleared, operation not allowed

Cause:	An operation encountered this online log in the middle of being cleared. The command that began the clearing may have terminated without completing the clearing.

Action:	If the clear command is still executing, then wait for its completion. If it terminated, then re-enter the clear command or drop the log.

ORA-00393 log name of thread num is needed for recovery of offline datafiles

Cause:	Log cannot be cleared because the redo in it is needed to recover offline datafiles. It has not been archived so there is no other copy available. If the log is cleared, the tablespaces containing the files will have to be dropped.

Action:	Archive the log, then repeat the clear command. If archiving is not possible and dropping the tablespaces is acceptable, then add the clause UNRECOVERABLE DATAFILE at the end of the clear command.