RMAN Block Media Recovery

From Oracle 9i onwards you can use RMAN to recover only blocks while database is up and running.
This could possibly save hours and hours of recovery time as a full database restore  is not necessary.
Error reported by user pointing to block corruption.

 POPULATE_MACSDATA - ORA-01578: ORACLE data block corrupted  (file # 48, block # 142713)
ORA-01110: data file 48: '/hqlinux08db06/ORACLE/macsl/MACSDAT_2006_06.dbf'
ORA-02063: preceding 2 lines from MODSL_MACSL_LINK
File name : /hqlinux08db06/ORACLE/macsl/MACSDAT_2006_06.dbf

Check first if the there is only one(few) blocks corrupted or most of the blocks are corrupted.

macsl:/opt/oracle/admin/macsl/bdump>
Issue command below at UNIX prompt.

dbv file=/hqlinux08db06/ORACLE/macsl/MACSDAT_2006_06.dbf BLOCKSIZE=8192 LOGFILE=test.log

DBV-00200: Block, dba 201469305, already marked corrupted

SQL> Select * from v$database_block_corruption;

You will get block number corrupt.
Ex: block 142713.

After that LOGIN TO RMAN.

rman target / catalog rman10/rman10@rman10p
RMAN> BLOCKRECOVER DATAFILE 48 BLOCK 142713;

V$database_block_corruption is the view to check the list of corrupted blocks.

If you have multiple block list as corrupt, You can use single command to recover them.

RMAN> BLOCKRECOVER corruption list;