Flashback query usage

-Initial setup - turn on Supplemental logging
    SQL>alter database add supplemental log data;
-Tunes the system to give the best possible undo retention for the undo tablespace.
    UNDO_MANAGEMENT
    UNDO_RETENTION
-Grant flashback privileges to users
    For the DBMS_FLASHBACK package, grant the EXECUTE privilege on DBMS_FLASHBACK
    For Flashback Transaction Query, grant the SELECT ANY TRANSACTION privilege.
    For Flashback Query and Flashback Version Query, grant FLASHBACK and SELECT privileges on specific objects to be accessed during queries or grant the FLASHBACK ANY TABLE privilege to allow queries on all tables.
-Using Flashback Query
    SELECT ... AS OF
    INSERT INTO ...(SELECT ... AS OF)
    CREATE ... AS SELECT ... AS OF