Enable block change tracking (BCT)
SQL> alter database enable block change tracking using file 'C:\app\neerajs\admin\noida\bct.dbf' ;
SQL> select filename, status, bytes from v$block_change_tracking;
To check whether the block change tracking file is being used or not, use the below command .
SQL> select file#, avg(datafile_blocks), avg(blocks_read), avg(blocks_read/datafile_blocks) * 100 as "% read for backup" from v$backup_datafile where incremental_level > 0 and used_change_tracking = 'YES' group by file# order by file# ;
To disable Block Change Tracking (BCT) issue the below command :
SQL> alter database disable block change tracking ;