General |
Note: Once enabled; this new 10g feature records the modified since last backup and stores the log of it in a block change tracking file.
During backups RMAN uses the log file to identify the specific blocks that
must be backed up. This improves RMAN's performance as it does not have to scan whole datafiles to detect
changed blocks.
Logging of changed blocks is performed by the CTWR process which is also
responsible for writing data to the block change tracking file. |
|
ENABLE |
Enable block change tracking |
conn / as sysdba
set linesize 121
col filename format
a60
SELECT filename, status, bytes
FROM v$block_change_tracking;
ALTER DATABASE ENABLE BLOCK CHANGE TRACKING
USING FILE 'c:\oracle\productlash_recovery_area\ORABASE\bctf01.log';
SELECT filename, status, bytes
FROM v$block_change_tracking; |
|
DISABLE |
Disable block change tracking |
conn / as sysdba
SELECT filename, status, bytes
FROM v$block_change_tracking;
ALTER DATABASE DISABLE BLOCK CHANGE
TRACKING;
SELECT filename, status, bytes
FROM v$block_change_tracking; |