如果丢失或损坏所有的控制文件就需要从备份中还原控制文件。restore controlfile命令用来还原控制文件。在还原控制文件后需要对数据亩执行完全介质恢复并以resetlog选项来打开数据库。RMAN可以将控制文件还原到它的默认存储位置，也可以使用restore controlfile ... to destination来指定位置。
从已经知的控制文件备份中还原控制文件
SQL> show parameter control_files
显示当前可用的备份
RMAN> list backup;
List of Backup Sets
===================
BS Key? Size? ? ? Device Type Elapsed Time Completion Time
------- ---------- ----------- ------------ ---------------
77? ? ? 693.50K? ? DISK? ? ? ? 00:00:02? ? 28-JAN-15
? ? ? ? BP Key: 75? Status: AVAILABLE? Compressed: YES? Tag: TAG20150128T131713
? ? ? ? Piece Name: /u02/test_df870182233_s95_s1
? List of Archived Logs in backup set 77
? Thrd Seq? ? Low SCN? ? Low Time? Next SCN? Next Time
? ---- ------- ---------- --------- ---------- ---------
? 1? ? 13? ? ? 2928236? ? 28-JAN-15 2928830? ? 28-JAN-15
BS Key? Type LV Size? ? ? Device Type Elapsed Time Completion Time
------- ---- -- ---------- ----------- ------------ ---------------
78? ? ? Full? ? 166.91M? ? DISK? ? ? ? 00:01:19? ? 28-JAN-15
? ? ? ? BP Key: 76? Status: AVAILABLE? Compressed: YES? Tag: TAG20150128T131716
? ? ? ? Piece Name: /u02/test_df870182236_s96_s1
? List of Datafiles in backup set 78
? File LV Type Ckp SCN? ? Ckp Time? Name
? ---- -- ---- ---------- --------- ----
? 1? ? ? Full 2928835? ? 28-JAN-15 /u01/app/oracle/oradata/test/system01.dbf
? 2? ? ? Full 2928835? ? 28-JAN-15 /u01/app/oracle/oradata/test/undotbs01.dbf
? 3? ? ? Full 2928835? ? 28-JAN-15 /u01/app/oracle/oradata/test/sysaux01.dbf
? 4? ? ? Full 2928835? ? 28-JAN-15 /u01/app/oracle/oradata/test/users01.dbf
? 5? ? ? Full 2928835? ? 28-JAN-15 /u01/app/oracle/oradata/test/example01.dbf
? 6? ? ? Full 2928835? ? 28-JAN-15 /u01/app/oracle/oradata/test/test01.dbf
BS Key? Size? ? ? Device Type Elapsed Time Completion Time
------- ---------- ----------- ------------ ---------------
79? ? ? 7.50K? ? ? DISK? ? ? ? 00:00:01? ? 28-JAN-15
? ? ? ? BP Key: 77? Status: AVAILABLE? Compressed: YES? Tag: TAG20150128T131841
? ? ? ? Piece Name: /u02/test_df870182321_s97_s1
? List of Archived Logs in backup set 79
? Thrd Seq? ? Low SCN? ? Low Time? Next SCN? Next Time
? ---- ------- ---------- --------- ---------- ---------
? 1? ? 14? ? ? 2928830? ? 28-JAN-15 2928868? ? 28-JAN-15
BS Key? Type LV Size? ? ? Device Type Elapsed Time Completion Time
------- ---- -- ---------- ----------- ------------ ---------------
80? ? ? Full? ? 9.42M? ? ? DISK? ? ? ? 00:00:02? ? 28-JAN-15
? ? ? ? BP Key: 78? Status: AVAILABLE? Compressed: NO? Tag: TAG20150128T131843
? ? ? ? Piece Name: /u01/app/oracle/10.2.0/db/dbs/c-2155613261-20150128-0d
? Control File Included: Ckp SCN: 2928874? ? ? Ckp time: 28-JAN-15
? SPFILE Included: Modification time: 28-JAN-15
?
?
从上面的信息可以看到备份集80是控制文件与spfile文件的备份
下面来删除当前数据库的所有控制文件：
[root@oracle11g ~]# cd /u01/app/oracle/oradata/test/
[root@oracle11g test]# ls -lrt
total 2213868
-rw-r----- 1 oracle oinstall? 11804672 Feb? 1 11:36 users01.dbf
-rw-r----- 1 oracle oinstall? 52436992 Feb? 1 11:36 test01.dbf
-rw-r----- 1 oracle oinstall? 52429312 Feb? 1 11:36 redo02.log
-rw-r----- 1 oracle oinstall? 52429312 Feb? 1 11:36 redo01.log
-rw-r----- 1 oracle oinstall 104865792 Feb? 1 11:36 example01.dbf
-rw-r----- 1 oracle oinstall? 20979712 Feb? 1 11:37 temp01.dbf
-rw-r----- 1 oracle oinstall 838868992 Feb? 1 19:05 system01.dbf
-rw-r----- 1 oracle oinstall 492838912 Feb? 1 19:05 undotbs01.dbf
-rw-r----- 1 oracle oinstall 576724992 Feb? 1 19:05 sysaux01.dbf
-rw-r----- 1 oracle oinstall? 52429312 Feb? 1 19:10 redo03.log
-rw-r----- 1 oracle oinstall? 98