Block Change Tracking

Block Change Tracking is an option to track datafile blocks affected by each database update. The tracking information is stored in a block change tracking file. When block change tracking is enabled, RMAN uses this file, to read those changed blocks. This improves incremental backup performance, as it saves time from reading all the data files for changed blocks. CTWR process logs the changed blocks to block change tracking file.

How to enable block change tracking

SQL> ALTER DATABASE ENABLE BLOCK CHANGE TRACKING USING FILE '/oradata/cost1/cost1TF.log';

How to disable block change tracking

SQL> ALTER DATABASE DISABLE BLOCK CHANGE TRACKING;

Monitor Block Change Tracking file

SQL> set lines 100

SQL> col filename for a45

SQL> select * from v$block_change_tracking;