恢复控制文件后，数据库使用resetlogs方式打开，在线日志的序列被重置。
SYS@practice >select group#,sequence#,archived,status,first_change#,next_change# from v$log;
GROUP# SEQUENCE# ARC STATUS FIRST_CHANGE# NEXT_CHANGE#
---------- ---------- --- ---------------- ------------- ------------
1 1 NO CURRENT 1014415 2.8147E+14
2 0 YES UNUSED 0 0
3 0 YES UNUSED 0 0
如果没有被resetlog截断的话当前日志的序列号应该是7，8，9
SYS@practice >select recid,sequence#,first_change#,next_change# from v$log_history;
RECID SEQUENCE# FIRST_CHANGE# NEXT_CHANGE#
---------- ---------- ------------- ------------
1 1 925702 955284
2 2 955284 955847
3 3 955847 971151
4 4 971151 987800
5 5 987800 997957
6 6 997957 1010981
7 1 1010981 1013463
8 2 1013463 1013471
9 3 1013471 1014415
如果恢复完控制文件，不使用resetlogs是打不开数据库的。
我们可以采取手工创建控制文件的方法打开数据库，保持联机日志的sequence#连续。下面的实验来演示具体操作过程。
在实验之前先手工切换3次日志，使得在线日志的序列号产生变化。在恢复结束后作为参考。
SYS@practice >alter system archive log current;
SYS@practice >alter system archive log current;
SYS@practice >alter system archive log current;
切换后当前连接日志状态如下
SYS@practice >select group#,sequence#,archived,status,first_change#,next_change# from v$log;
GROUP# SEQUENCE# ARC STATUS FIRST_CHANGE# NEXT_CHANGE#
---------- ---------- --- ---------------- ------------- ------------
1 4 NO CURRENT 1030130 2.8147E+14
2 2 YES INACTIVE 1030109 1030117
3 3 YES ACTIVE 1030117 1030130
1，恢复控制文件
RMAN> startup force nomount;
Total System Global Area 580395008 bytes
Fixed Size 2255392 bytes
Variable Size 402654688 bytes
Database Buffers 171966464 bytes
Redo Buffers 3518464 bytes
RMAN> restore controlfile from autobackup;
Starting restore at 06-OCT-14
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=19 device type=DISK
recovery area destination: /u01/fast_recovery_area
database name (or database unique name) used for search: PRACTICE
channel ORA_DISK_1: AUTOBACKUP /u01/fast_recovery_area/PRACTICE/autobackup/2014_10_06/o1_mf_s_860251717_b35s05gm_.bkp found in the recovery area
channel ORA_DISK_1: looking for AUTOBACKUP on day: 20141006
channel ORA_DISK_1: restoring control file from AUTOBACKUP /u01/fast_recovery_area/PRACTICE/autobackup/2014_10_06/o1_mf_s_860251717_b35s05gm_.bkp
channel ORA_DISK_1: control file restore from AUTOBACKUP complete
output file name=/u01/oradata/practice/control01.ctl
output file name=/u01/fast_recovery_area/practice/control02.ctl
Finished restore at 06-OCT-14
2，启动数据库到mount状态
RMAN> mount database;
database mounted
released channel: ORA_DISK_1
3，恢复数据库
RMAN> recover database;
Starting recover at 06-OCT-14
Starting implicit crosscheck backup at 06-OCT-14
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=20 device type=DISK
Crosschecked 6 objects
Finished implicit crosscheck backup at 06-OCT-14
Starting implicit crosscheck copy at 06-OCT-14
using channel ORA_DISK_1
Finished implicit crosscheck copy at 06-OCT-14
searching for all files in the recovery area
cataloging files...
cataloging done
List of Cataloged Files
=======================
File Name: /u01