DBA_LOGSTDBY_EVENTS displays information about the activity of the logical standby database system. It can be used to determine the cause of failures that occur when applying redo data to logical standby databases. This view is for logical standby databases only.
Time the event was logged
Timestamp when the event was logged
Change vector SCN for the change. If a failure occurred, then examine this column to determine which archived log file contains the source of the failure (for example, an unsupported record).
SCN value on which the change was committed
Transaction ID undo segment number
Transaction ID slot number
Transaction ID sequence number
Statement that was being processed when the failure occurred
Status (or Oracle error code) belonging to the STATUS message
Description of the current activity of the process or the reason why the apply operation stopped