--
-- Redo Generation Cost of Backup Mode Demo
--
drop table test purge ;
create table test as select * from all_objects ;

select object_name from test where object_id = 5000 ;

set autotrace traceonly statistics

update test set object_name='TEST 1 5000' where object_id = 5000 ;

Statistics
----------------------------------------------------------
          6  recursive calls
          2  db block gets
        755  consistent gets
          0  physical reads
        436  redo size
        667  bytes sent via SQL*Net to client
        601  bytes received via SQL*Net from client
          3  SQL*Net roundtrips to/from client
          2  sorts (memory)
          0  sorts (disk)
          1  rows processed
		  
alter database begin backup;

update test set object_name='TEST 2 5000' where object_id = 5000 ;

Statistics
----------------------------------------------------------
          4  recursive calls
          1  db block gets
        754  consistent gets
          0  physical reads
      16820  redo size
        667  bytes sent via SQL*Net to client
        601  bytes received via SQL*Net from client
          3  SQL*Net roundtrips to/from client
          1  sorts (memory)
          0  sorts (disk)
          1  rows processed

update test set object_name='TEST 3 5000' where object_id = 5000 ;

Statistics
----------------------------------------------------------
          4  recursive calls
          1  db block gets
        754  consistent gets
          0  physical reads
        364  redo size
        667  bytes sent via SQL*Net to client
        601  bytes received via SQL*Net from client
          3  SQL*Net roundtrips to/from client
          1  sorts (memory)
          0  sorts (disk)
          1  rows processed

alter database end backup;