SQL> alter database datafile '/oradata/data/standby/data/t2.dbf' offline;
Database altered.
SQL> c/off/on/
1* alter database datafile '/oradata/data/standby/data/t2.dbf' online
SQL> /
alter database datafile '/oradata/data/standby/data/t2.dbf' online
*
ERROR at line 1:
ORA-01113: file 13 needs media recovery
ORA-01110: data file 13: '/oradata/data/standby/data/t2.dbf'
SQL> recover datafile 13;
Media recovery complete.
SQL>
SQL>
SQL> select * from v$recover_file;
FILE# ONLINEONLINE_
---------- ------- -------
ERROR
CHANGE#
----------------------------------------------------------------- ----------
TIME
---------
12 OFFLINE OFFLINE
1187252
28-JUN-08
SQL> alter database datafile 12 online;
alter database datafile 12 online
*
ERROR at line 1:
ORA-01113: file 12 needs media recovery
ORA-01110: data file 12: '/oradata/data/standby/data/t1.dbf'
SQL> recover datafile 12 ;
Media recovery complete.
SQL> alter database datafile 12 online;
Database altered.