Undo Log Management
During
online logging
, the
undo log entries
are managed. The
modifying transactions
store the undo log entries in
undo log files
.
Use
Undo log management plays a part in the following actions:
The database can create a transaction-consistent database state that reflects the state of the database system at the time of the last
savepoint
. The information in the undo log files is sufficient for this.
In a
restart or recovery
, the required undo log entries are determined.
For the database instance type
liveCache
,
History Management
is carried out for the undo log entries.