Enable FlashBack on Database

shutdown immediate;
startup mount;
alter database archivelog;
alter system set DB_FLASHBACK_RETENTION_TARGET=600 scope =both;
alter system set DB_RECOVERY_FILE_DEST_SIZE=2G;
alter system set DB_RECOVERY_FILE_DEST=’/oraarch/xxxxx/archivelog’
alter database flashback on;
alter database open;

Useful Query

SQL> show parameter recovery;

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest                string      /oraarch/xxxxx/archivelog
db_recovery_file_dest_size           big integer 8G



SQL> select db_unique_name,log_mode,open_mode,flashback_on,force_logging from v$database;

DB_UNIQUE_NAME                 LOG_MODE     OPEN_MODE            FLASHBACK_ON       FORCE_LOGGING

------------------------------ ------------ -------------------- ------------------ ---------------------------------------

xxxxx                                        ARCHIVELOG   READ WRITE               YES                              YES

View Fast Recovery disk

select estimated_flashback_size,flashback_size from v$flashback_database_log;

Determine the current flashback window

Select oldest_flashback_scn, oldest_flashback_time from v$flashback_database_log;