注意：数据库应该支持在归档模式。
1.对SYSTEMG表空间做一个备份
[Oracle@bys001 ~]$ rman target /
Recovery Manager: Release 11.2.0.1.0 - Production on Tue Sep 17 10:42:18 2013
Copyright (c) 1982, 2009, Oracle and/or its affiliates. All rights reserved.
connected to target database: BYS1 (DBID=3957527513)
RMAN> list backup;
using target database control file instead of recovery catalog
specification does not match any backup in the repository
RMAN> backup tablespace system;
Starting backup at 17-SEP-13
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=45 device type=DISK
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00001 name=/u01/oradata/bys1/system01.dbf
channel ORA_DISK_1: starting piece 1 at 17-SEP-13
channel ORA_DISK_1: finished piece 1 at 17-SEP-13
piece handle=/u01/flash_recovery_area/BYS1/backupset/2013_09_17/o1_mf_nnndf_TAG20130917T104438_93hjjqph_.bkp tag=TAG20130917T104438 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:02:26
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
including current control file in backup set
including current SPFILE in backup set
channel ORA_DISK_1: starting piece 1 at 17-SEP-13
channel ORA_DISK_1: finished piece 1 at 17-SEP-13
piece handle=/u01/flash_recovery_area/BYS1/backupset/2013_09_17/o1_mf_ncsnf_TAG20130917T104438_93hjok2q_.bkp tag=TAG20130917T104438 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:03
Finished backup at 17-SEP-13
RMAN> exit
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