SET FEEDBACK ON is a synonym for the SQL SET DISPLAY NO ROW
    COUNTER statement. SQL data manipulation statements such as
    SELECT, DELETE, UPDATE, and INSERT will display the number of
    affected rows. SET FEEDBACK n sets a limit value which turns on
    feedback only if more than 'n' rows are displayed. SET FEEDBACK
    0 is synonymous with SET FEEDBACK ON. SET FEEDBACK OFF is a
    synonym for the SQL SET DISPLAY ROW COUNTER statement. SQL data
    manipulation statements no longer display the count of affected
    rows.

    SQL> set feedback 2
    SQL> select * from work_status;
     STATUS_CODE   STATUS_NAME   STATUS_TYPE
     0             INACTIVE      RECORD EXPIRED
     1             ACTIVE        FULL TIME
     2             ACTIVE        PART TIME
    3 rows selected
    SQL> set feedback 4
    SQL> select * from work_status;
     STATUS_CODE   STATUS_NAME   STATUS_TYPE
     0             INACTIVE      RECORD EXPIRED
     1             ACTIVE        FULL TIME
     2             ACTIVE        PART TIME