Proactive Health Checks

Bagaimana kita tahu tidak ada bad blocks dalam database kita, karena bad blocks dapat ketahuan saat kita mengaksesnya.
dan bagaimana kita dapat mengidentifikasinya sebelum itu terjadi, dan memperbaikinya sblm error dialami oleh user.
Dalam Oracle 11g, dengan perintah baru dalam RMAN yaitu VALIDATE DATABASE.dapat melakukan operasi untuk melakukan cek
terhadap database blocks dari physical corruption.

RMAN> validate database;

Starting validate at 09-SEP-07
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=110 device type=DISK
channel ORA_DISK_1: starting validation of datafile
channel ORA_DISK_1: specifying datafile(s) for validation
input datafile file number=00002 name=/home/oracle/oradata/ODEL11/sysaux01.dbf
input datafile file number=00001 name=/home/oracle/oradata/ODEL11/system01.dbf
input datafile file number=00003 name=/home/oracle/oradata/ODEL11/undotbs01.dbf
input datafile file number=00004 name=/home/oracle/oradata/ODEL11/users01.dbf
channel ORA_DISK_1: validation complete, elapsed time: 00:02:18
List of Datafiles
=================
File Status Marked Corrupt Empty Blocks Blocks Examined High SCN
—- —— ————– ———— ————— ———-
1 OK 0 12852 94720 5420717
File Name: /home/oracle/oradata/ODEL11/system01.dbf
Block Type Blocks Failing Blocks Processed
———- ————– —————-
Data 0 65435
Index 0 11898
Other 0 4535

File Status Marked Corrupt Empty Blocks Blocks Examined High SCN
—- —— ————– ———— ————— ———-
2 OK 0 30753 115848 5420730
File Name: /home/oracle/oradata/ODEL11/sysaux01.dbf
Block Type Blocks Failing Blocks Processed
———- ————– —————-
Data 0 28042
Index 0 26924
Other 0 30129

File Status Marked Corrupt Empty Blocks Blocks Examined High SCN
—- —— ————– ———— ————— ———-
3 OK 0 5368 25600 5420730
File Name: /home/oracle/oradata/ODEL11/undotbs01.dbf
Block Type Blocks Failing Blocks Processed
———- ————– —————-
Data 0 0
Index 0 0
Other 0 20232

File Status Marked Corrupt Empty Blocks Blocks Examined High SCN
—- —— ————– ———— ————— ———-
4 OK 0 2569 12256 4910970

… <<dipotong..>> …
Sebaliknya misalnya terdapat error maka output dari oracle adalah seperti dibawah

List of Datafiles
=================
File Status Marked Corrupt Empty Blocks Blocks Examined High SCN
—- —— ————– ———— ————— ———-
7 FAILED 0 0 128 5556154
File Name: /home/oracle/oradata/ODEL11/test01.dbf
Block Type Blocks Failing Blocks Processed
———- ————– —————-
Data 0 108
Index 0 0
Other 10 20

Kita juga dapat melakukan validasi terhadap tablespace yang spesifik

RMAN> validate tablespace dataku;

Starting validate at 02-JUL-08
using channel ORA_DISK_1
channel ORA_DISK_1: starting validation of datafile
channel ORA_DISK_1: specifying datafile(s) for validation
input datafile file number=00006 name=C:\APP\ADMINISTRATOR\ORADATA\ORCL\DATAKU

channel ORA_DISK_1: validation complete, elapsed time: 00:00:03
List of Datafiles
=================
File Status Marked Corrupt Empty Blocks Blocks Examined High SCN
—- —— ————– ———— ————— ———-
6 OK 0 12766 12800 1433028
File Name: C:\APP\ADMINISTRATOR\ORADATA\ORCL\DATAKU
Block Type Blocks Failing Blocks Processed
———- ————– —————-
Data 0 10
Index 0 1
Other 0 23

Finished validate at 02-JUL-08

Atau kita lakukan validasi terhadap datafile

RMAN> validate datafile 1;

Ataupun block dalam sebuah datafile;

RMAN> validate datafile 4 block 56;

Selain datafile kita juga bisa melakukan validasi terhadap spfile, controlfilecopy, recovery file, Flash Recovery Area