How to enable or disable BCT in Oracle Database?

Block changing tracking improves the performance of incremental backups by recording changed blocks in the block change tracking file. During an incremental backup, instead of scanning all data blocks to identify which blocks have changed, RMAN uses this file to identify the changed blocks that need to be backed up.

Enabling the BCT will improves the RMAN incremental performance

To determine if block change tracking is enabled or not

[oracle@oracledb ~]$ . oraenv

ORACLE_SID = [ORACDB] ?

The Oracle base remains unchanged with value /u01/app/oradev

[oracle@oracledb ~]$ sqlplus / as sysdba

SQL*Plus: Release 19.0.0.0.0 - Production on Fri Oct 8 21:18:19 2021

Version 19.3.0.0.0

Copyright (c) 1982, 2019, Oracle.  All rights reserved.

Connected to:

Oracle Database 19c Enterprise Edition Release 19.0.0.0.0 - Production

Version 19.3.0.0.0

SQL> SELECT status, filename FROM V$BLOCK_CHANGE_TRACKING;

STATUS FILENAME

---------- ------------

DISABLED

SQL>

Enable:

Enable the block change tracing using below command and verify the same:

SQL> ALTER DATABASE ENABLE BLOCK CHANGE TRACKING;

Database altered.

SQL>

SQL> SELECT status, filename FROM V$BLOCK_CHANGE_TRACKING;

STATUS FILENAME

---------- --------------------------------------------------------------------------------

ENABLED /u01/app/oradev/oradata/ORACDB/ORACDB/changetracking/o1_mf_jp0t5bt0_.chg

Disable:

Disable the block change tracing using below command and verify the same:

SQL> ALTER DATABASE DISABLE BLOCK CHANGE TRACKING;

Database altered.

SQL> SELECT status, filename FROM V$BLOCK_CHANGE_TRACKING;

STATUS FILENAME

---------- --------------------------------------------------------------------------------

DISABLED

Regards,

Mallik