Block Corruption

Oracle database corruption

Oracle data block may get damaged or corrupt due to any of the following reasons:
 A hardware component has malfunctioned.
 The system has some incompatible device drivers.
 You are facing several paging and memory issues.

dbv file=/u01/app/oracle/oradata/orcl/test_corrupt01.dbf
DBVERIFY – Verification starting : FILE = /u01/app/oracle/oradata/orcl/test_corrupt01.dbf

Page 142 is marked corrupt
.
.
.
Total Pages Encrypted : 0

Highest block SCN : 1263187 (0.1263187)

RMAN> recover datafile 4 block 142;

BACKUP VALIDATE DATABASE ARCHIVELOG ALL;

RESTORE DATABASE VALIDATE;
RESTORE ARCHIVELOG ALL VALIDATE;
RESTORE VALIDATE command mimics the process of a restore, without actually performing the restore

VALIDATE DATAFILE 1;
VALIDATE TABLESPACE users;
VALIDATE CHECK LOGICAL DATABASE ARCHIVELOG ALL;
Outputs the same information you would see during a backup, but no backup is created. Block corruptions are visible in the V$DATABASE_BLOCK_CORRUPTION