Login as sys user and run the below command to verify if database log mode is in archive mode or no archive mode.
SQL>archive log list;
Database log mode No Archive Mode
Automatic archival Disabled
Archive destination USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence 19
Current log sequence 21
You might get the value as shown above and if you notice the “Database log mode” is in “No Archive Mode”, then you need to enable it by running the below commands:
SQL>alter database archivelog;
SQL> alter database open;
To issue the SQL command to put the database in ARCHIVELOG mode, the database must be in MOUNTmode. If the database is currently open, you must shut it down cleanly (not abort), and then mount it.
With the database in NOARCHIVELOG mode (the default), recovery is possible only until the time of the last backup. All transactions made after that backup are lost.
In ARCHIVELOG mode, recovery is possible until the time of the last commit. Most production databases are operated in ARCHIVELOG mode.
To see the current archiving mode, query the
SQL> select log_mode from sys.v$database;