How to Enable/Disable Flashback in Oracle Database Posted by MOHAMMED ABDUL HAMEED on 6:49 AM

1.Database has to be in Archivelog mode

      SQL> select log_mode from v$database;

               LOG_MODE
                ------------
NOARCHIVELOG

     SQL> shutdown immediate;
              Database closed.
              Database dismounted.
              ORACLE instance shut down.

    SQL> startup mount;
ORACLE instance started.

Total System Global Area 1573527552 bytes
Fixed Size                  1345184 bytes
Variable Size             436210016 bytes
Database Buffers         1124073472 bytes
Redo Buffers               11898880 bytes
Database mounted.

    SQL> alter database archivelog;

Database altered.

   SQL> alter database open;

Database altered.

    SQL> archive log list

         Database log mode              Archive Mode
Automatic archival                Enabled
Archive destination                                                                              USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence        22
Next log sequence to archive      24
Current log sequence                 24

  SQL> select log_mode from v$database;

              LOG_MODE
               ------------
             ARCHIVELOG

2. Configure Flash Recovery Area.

3.To enable or disable flashback , we can change this while database is in open mode.


     SQL> select open_mode from v$database;

OPEN_MODE
--------------------
READ WRITE

   SQL> select flashback_on from v$database;

           FLASHBACK_ON
             ------------------
               NO

   SQL> alter database flashback on;

           Database altered.

  SQL> select flashback_on from v$database;

           FLASHBACK_ON
            ------------------
                YES

  SQL> alter database flashback off;

           Database altered.

  SQL> select flashback_on from v$database;

           FLASHBACK_ON
             ------------------
                 NO