566.You have lost all your SYSTEM tablespace datafiles (system_01.dbf and system_02.dbf) nd the
database has crashed.
What would be the appropriate order of operations to correct the situation?
A. Mount the database with the startup mount command.
B. Take the SYSTEM datafile offline with the alter database command.
C. Restore the SYSTEM_01.dbf datafile from backup media with the required archived redo logs.
D. Restore all SYSTEM tablespace-related datafiles from backup media.
E. Issue the recover tablespace SYSTEM command.
F. Issue the recover datafile SYSTEM_01.dbf command.
G. Open the database with the alter database open command.
H. Open the database with the alter database open resetlogs command.
I. a, c, f, g
J. b, d, e, h
K. a, b, c, f, g
L. d, a, e, g
M. b, c, f, e, g
Answer: D

[oracle@db01 inst1]$ ls -l
total 2221040
-rw-r-----. 1 oracle oinstall  10076160 Mar 25 11:22 control01.ctl
-rw-r-----. 1 oracle oinstall 363077632 Mar 25 11:20 example01.dbf
-rw-r-----. 1 oracle oinstall  52429312 Mar 25 11:21 redo01.log
-rw-r-----. 1 oracle oinstall  52429312 Mar 25 11:21 redo02.log
-rw-r-----. 1 oracle oinstall  52429312 Mar 25 11:20 redo03.log
-rw-r-----. 1 oracle oinstall 650125312 Mar 25 11:20 sysaux01.dbf
-rw-r-----. 1 oracle oinstall 796925952 Mar 25 11:20 system01.dbf
-rw-r-----. 1 oracle oinstall  30416896 Mar 10 05:18 temp01.dbf
-rw-r-----. 1 oracle oinstall  52436992 Mar  9 22:22 temp02.dbf
-rw-r-----. 1 oracle oinstall  52436992 Mar 25 05:40 temp03.dbf
-rw-r-----. 1 oracle oinstall 104865792 Mar 25 11:20 ts_test.dbf
-rw-r-----. 1 oracle oinstall  99622912 Mar 25 11:20 undotbs01.dbf
-rw-r-----. 1 oracle oinstall  52436992 Mar 25 11:20 user_data01.dbf
-rw-r-----. 1 oracle oinstall   5251072 Mar 25 11:20 users01.dbf
[oracle@db01 inst1]$ rm system01.dbf 
[oracle@db01 inst1]$ sqlplus / as sysdba


SQL*Plus: Release 11.2.0.4.0 Production on Fri Mar 25 11:22:42 2016


Copyright (c) 1982, 2013, Oracle.  All rights reserved.




Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options


SQL> shutdown immediate
ORA-01116: error in opening database file 1
ORA-01110: data file 1: '/u01/app/oracle/oradata/inst1/system01.dbf'
ORA-27041: unable to open file
Linux-x86_64 Error: 2: No such file or directory
Additional information: 3
SQL> shutdown abort
ORACLE instance shut down.
SQL> quit  

RMAN恢复：

[oracle@db01 inst1]$ rman target /


Recovery Manager: Release 11.2.0.4.0 - Production on Fri Mar 25 11:24:15 2016


Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved.


connected to target database (not started)


RMAN> startup mount


Oracle instance started
database mounted


Total System Global Area     413372416 bytes


Fixed Size                     2253784 bytes
Variable Size                318770216 bytes
Database Buffers              83886080 bytes
Redo Buffers                   8462336 bytes

RMAN> restore datafile 1;


Starting restore at 25-MAR-16
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=134 device type=DISK
allocated channel: ORA_DISK_2
channel ORA_DISK_2: SID=11 device type=DISK


channel ORA_DISK_1: starting datafile backup set restore
channel ORA_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_DISK_1: restoring datafile 00001 to /u01/app/oracle/oradata/inst1/system01.dbf
channel ORA_DISK_1: reading from backup piece /u01/app/oracle/2gr1c23g_1_1
channel ORA_DISK_1: piece handle=/u01/app/oracle/2gr1c23g_1_1 tag=TAG20160325T112016
channel ORA_DISK_1: restored backup piece 1
channel ORA_DISK_1: restore complete, elapsed time: 00:00:25
Finished restore at 25-MAR-16


RMAN> recover datafile 1;


Starting recover at 25-MAR-16
using channel ORA_DISK_1
using channel ORA_DISK_2


starting media recovery
media recovery complete, elapsed time: 00:00:01


Finished recover at 25-MAR-16


RMAN> alter database open;


database opened


参考：http://blog.csdn.net/rlhua/article/details/13774369