对于数据库而言，如果丢失数据文件不在system和undo表空间，就视为不重要数据文件

前提：已经使用RMAN备份过数据库

步骤：

1、如果数据文件处于打开状态，就使表空间offline

2、restore

3、recover

4、online

查看当前所有数据文件

SQL> select name from v$datafile;

NAME

--------------------------------------------------------------------------------

/home/oracle/app/oracle/oradata/sap/system01.dbf

/home/oracle/app/oracle/oradata/sap/sysaux01.dbf

/home/oracle/app/oracle/oradata/sap/undotbs01.dbf

/home/oracle/app/oracle/oradata/sap/users01.dbf

/home/oracle/app/oracle/oradata/sap/example01.dbf

/home/oracle/app/oracle/oradata/sap/lztest.dbf

6 rows selected.

数据库运行中强制删除数据文件/home/oracle/app/oracle/oradata/sap/users01.dbf

rm /home/oracle/app/oracle/oradata/sap/users01.dbf

SQL> shutdown

ORA-01116: error in opening database file 4

ORA-01110: data file 4: '/home/oracle/app/oracle/oradata/sap/users01.dbf'

ORA-27041: unable to open file

Linux-x86_64 Error: 2: No such file or directory

Additional information: 3

SQL> alter tablespace users offline immediate;

Tablespace altered.

RMAN> restore tablespace users;

Starting restore at 03-MAR-14

starting full resync of recovery catalog

full resync complete

allocated channel: ORA_DISK_1

channel ORA_DISK_1: SID=192 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 00004 to /home/oracle/app/oracle/oradata/sap/users01.dbf

channel ORA_DISK_1: restoring section 1 of 3

channel ORA_DISK_1: reading from backup piece /home/oracle/app/oracle/flash_recovery_area/SAP/backupset/2014_03_03/o1_mf_nnndf_TAG20140303T063924_9k950wdb_.bkp

channel ORA_DISK_1: piece handle=/home/oracle/app/oracle/flash_recovery_area/SAP/backupset/2014_03_03/o1_mf_nnndf_TAG20140303T063924_9k950wdb_.bkp tag=TAG20140303T063924

channel ORA_DISK_1: restored backup piece 1

channel ORA_DISK_1: restore complete, elapsed time: 00:00:01

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 00004 to /home/oracle/app/oracle/oradata/sap/users01.dbf

channel ORA_DISK_1: restoring section 2 of 3

channel ORA_DISK_1: reading from backup piece /home/oracle/app/oracle/flash_recovery_area/SAP/backupset/2014_03_03/o1_mf_nnndf_TAG20140303T063924_9k950xhw_.bkp

channel ORA_DISK_1: piece handle=/home/oracle/app/oracle/flash_recovery_area/SAP/backupset/2014_03_03/o1_mf_nnndf_TAG20140303T063924_9k950xhw_.bkp tag=TAG20140303T063924

channel ORA_DISK_1: restored backup piece 2

channel ORA_DISK_1: restore complete, elapsed time: 00:00:01

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 00004 to /home/oracle/app/oracle/oradata/sap/users01.dbf

channel ORA_DISK_1: restoring section 3 of 3

channel ORA_DISK_1: reading from backup piece /home/oracle/app/oracle/flash_recovery_area/SAP/backupset/2014_03_03/o1_mf_nnndf_TAG20140303T063924_9k950yoo_.bkp

channel ORA_DISK_1: piece handle=/home/oracle/app/oracle/flash_recovery_area/SAP/backupset/2014_03_03/o1_mf_nnndf_TAG20140303T063924_9k950yoo_.bkp tag=TAG20140303T063924

channel ORA_DISK_1: restored backup piece 3

channel ORA_DISK_1: restore complete, elapsed time: 00:00:01

Finished restore at 03-MAR-14

RMAN> recover tablespace users;

Starting recover at 03-MAR-14

using channel ORA_DISK_1

starting media recovery

archived log for thread 1 with sequence 13 is already on disk as file /home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_13_9kbhlkwh_.arc

archived log for thread 1 with sequence 14 is already on disk as file /home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_14_9kbhm25o_.arc

archived log for thread 1 with sequence 15 is already on disk as file /home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_15_9kbhmfx5_.arc

archived log for thread 1 with sequence 16 is already on disk as file /home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_16_9kbhmsw5_.arc

archived log for thread 1 with sequence 17 is already on disk as file /home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_17_9kbhn87m_.arc

archived log for thread 1 with sequence 18 is already on disk as file /home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_18_9kbhtkfl_.arc

archived log for thread 1 with sequence 19 is already on disk as file /home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_19_9kbhvogj_.arc

archived log for thread 1 with sequence 20 is already on disk as file /home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_20_9kbhwctk_.arc

archived log for thread 1 with sequence 21 is already on disk as file /home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_21_9kbhxcrg_.arc

archived log for thread 1 with sequence 22 is already on disk as file /home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_22_9kbhy5nw_.arc

archived log file name=/home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_13_9kbhlkwh_.arc thread=1 sequence=13

archived log file name=/home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_14_9kbhm25o_.arc thread=1 sequence=14

archived log file name=/home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_15_9kbhmfx5_.arc thread=1 sequence=15

archived log file name=/home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_16_9kbhmsw5_.arc thread=1 sequence=16

archived log file name=/home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_17_9kbhn87m_.arc thread=1 sequence=17

archived log file name=/home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_18_9kbhtkfl_.arc thread=1 sequence=18

archived log file name=/home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_19_9kbhvogj_.arc thread=1 sequence=19

archived log file name=/home/oracle/app/oracle/flash_recovery_area/SAP/archivelog/2014_03_03/o1_mf_1_20_9kbhwctk_.arc thread=1 sequence=20

media recovery complete, elapsed time: 00:00:03

Finished recover at 03-MAR-14

RMAN> sql 'alter tablespace users online';

sql statement: alter tablespace users online

在数据库关闭状态删除 users文件

[root@sap trace]# mv /home/oracle/app/oracle/oradata/sap/users01.dbf /home/oracle/app/oracle/oradata/sap/users01.dbf_del

启动数据库，报错

SQL> startup

ORACLE instance started.

Total System Global Area 830930944 bytes

Fixed Size 2217912 bytes

Variable Size 503318600 bytes

Database Buffers 318767104 bytes

Redo Buffers 6627328 bytes

Database mounted.

ORA-01157: cannot identify/lock data file 4 - see DBWR trace file

ORA-01110: data file 4: '/home/oracle/app/oracle/oradata/sap/users01.dbf'

[oracle@sap ~]$ rman target / catalog rman/rman@catalog:1521/catalog

Recovery Manager: Release 11.2.0.1.0 - Production on Mon Mar 3 20:35:13 2014

connected to target database: SAP (DBID=3375191994, not open)

connected to recovery catalog database

RMAN>

恢复表空间

RMAN> restore tablespace users;

Starting restore at 03-MAR-14

allocated channel: ORA_DISK_1

channel ORA_DISK_1: SID=129 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 00004 to /home/oracle/app/oracle/oradata/sap/users01.dbf

channel ORA_DISK_1: restoring section 1 of 3

channel ORA_DISK_1: reading from backup piece /home/oracle/app/oracle/flash_recovery_area/SAP/backupset/2014_03_03/o1_mf_nnndf_TAG20140303T063924_9k950wdb_.bkp

channel ORA_DISK_1: piece handle=/home/oracle/app/oracle/flash_recovery_area/SAP/backupset/2014_03_03/o1_mf_nnndf_TAG20140303T063924_9k950wdb_.bkp tag=TAG20140303T063924

channel ORA_DISK_1: restored backup piece 1

channel ORA_DISK_1: restore complete, elapsed time: 00:00:01

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 00004 to /home/oracle/app/oracle/oradata/sap/users01.dbf

channel ORA_DISK_1: restoring section 2 of 3

channel ORA_DISK_1: reading from backup piece /home/oracle/app/oracle/flash_recovery_area/SAP/backupset/2014_03_03/o1_mf_nnndf_TAG20140303T063924_9k950xhw_.bkp

channel ORA_DISK_1: piece handle=/home/oracle/app/oracle/flash_recovery_area/SAP/backupset/2014_03_03/o1_mf_nnndf_TAG20140303T063924_9k950xhw_.bkp tag=TAG20140303T063924

channel ORA_DISK_1: restored backup piece 2

channel ORA_DISK_1: restore complete, elapsed time: 00:00:01

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 00004 to /home/oracle/app/oracle/oradata/sap/users01.dbf

channel ORA_DISK_1: restoring section 3 of 3

channel ORA_DISK_1: reading from backup piece /home/oracle/app/oracle/flash_recovery_area/SAP/backupset/2014_03_03/o1_mf_nnndf_TAG20140303T063924_9k950yoo_.bkp

channel ORA_DISK_1: piece handle=/home/oracle/app/oracle/flash_recovery_area/SAP/backupset/2014_03_03/o1_mf_nnndf_TAG20140303T063924_9k950yoo_.bkp tag=TAG20140303T063924

channel ORA_DISK_1: restored backup piece 3

channel ORA_DISK_1: restore complete, elapsed time: 00:00:01

Finished restore at 03-MAR-14

RMAN> recover tablespace users;