使用RMAN对数据文件进行恢复

（1）备份数据库

在使用RMAN进行数据库恢复之前，先用RMAN进行全库备份

[oracle@redhat6 ~]$ rman target /

Recovery Manager: Release 11.2.0.1.0 - Production on Wed May 16 14:32:54 2018

Copyright (c) 1982, 2009, Oracle and/or its affiliates.  All rights reserved.

connected to target database: ORCL (DBID=1486787650)

RMAN> backup database;

Starting backup at 16-MAY-18
using channel ORA_DISK_1
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/app/oracle/oradata/orcl/system01.dbf
input datafile file number=00002 name=/u01/app/oracle/oradata/orcl/sysaux01.dbf
input datafile file number=00003 name=/u01/app/oracle/oradata/orcl/undotbs01.dbf
input datafile file number=00005 name=/u01/app/oracle/oradata/orcl/example01.dbf
input datafile file number=00009 name=/u01/app/oracle/oradata/orcl/mark.bdf
input datafile file number=00011 name=/u01/app/oracle/oradata/orcl/tbs01.bdf
input datafile file number=00012 name=/u01/app/oracle/oradata/orcl/tbs03.dbf
input datafile file number=00013 name=/u01/app/oracle/oradata/orcl/tbs04.dbf
input datafile file number=00004 name=/u01/app/oracle/oradata/orcl/users01.dbf
channel ORA_DISK_1: starting piece 1 at 16-MAY-18
channel ORA_DISK_1: finished piece 1 at 16-MAY-18
piece handle=/u01/app/oracle/product/11.2.0/db_1/dbs/01t31soh_1_1 tag=TAG20180516T144121 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:02:33
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00008 name=/u01/app/oracle/oradata/orcl/tbs_32k.dbf
channel ORA_DISK_1: starting piece 1 at 16-MAY-18
channel ORA_DISK_1: finished piece 1 at 16-MAY-18
piece handle=/u01/app/oracle/product/11.2.0/db_1/dbs/02t31sta_1_1 tag=TAG20180516T144121 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
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 16-MAY-18
channel ORA_DISK_1: finished piece 1 at 16-MAY-18
piece handle=/u01/app/oracle/product/11.2.0/db_1/dbs/03t31stc_1_1 tag=TAG20180516T144121 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
Finished backup at 16-MAY-18

（2）删除数据文件

查看数据库的数据文件信息：

select      t."NAME",
            d."NAME",
            d."FILE#"
from        v$tablespace  t,
            v$datafile d
where       t."TS#" = d."TS#"
order by t.ts#;

NAME                           NAME                                                                                  FILE#
------------------------------ -------------------------------------------------------------------------------- ----------
SYSTEM                         /u01/app/oracle/oradata/orcl/system01.dbf                                                 1
SYSAUX                         /u01/app/oracle/oradata/orcl/sysaux01.dbf                                                 2
UNDOTBS1                       /u01/app/oracle/oradata/orcl/undotbs01.dbf                                                3
USERS                          /u01/app/oracle/oradata/orcl/users01.dbf                                                  4
EXAMPLE                        /u01/app/oracle/oradata/orcl/example01.dbf                                                5
TBS_32K                        /u01/app/oracle/oradata/orcl/tbs_32k.dbf                                                  8
MARK                           /u01/app/oracle/oradata/orcl/mark.bdf                                                     9
TBS01                          /u01/app/oracle/oradata/orcl/tbs01.bdf                                                   11
TBS03                          /u01/app/oracle/oradata/orcl/tbs03.dbf                                                   12
TBS04                          /u01/app/oracle/oradata/orcl/tbs04.dbf                                                   13
10 rows selected

删除一个数据文件，这里把文件编号为13的数据文件给删除：

[oracle@redhat6 ~]$ rm -f /u01/app/oracle/oradata/orcl/tbs04.dbf

（3）恢复数据文件

（3.1）使用list failure查看失败操作

RMAN> list failure;

List of Database Failures
=========================

Failure ID Priority Status    Time Detected Summary
---------- -------- --------- ------------- -------
8          HIGH     OPEN      16-MAY-18     One or more non-system datafiles need media recovery
42         HIGH     OPEN      13-DEC-17     One or more non-system datafiles are missing

（3.2）使用RMAN建议来恢复丢失的文件

RMAN> advise failure
2> ;

List of Database Failures
=========================

Failure ID Priority Status    Time Detected Summary
---------- -------- --------- ------------- -------
8          HIGH     OPEN      16-MAY-18     One or more non-system datafiles need media recovery
42         HIGH     OPEN      13-DEC-17     One or more non-system datafiles are missing

analyzing automatic repair options; this may take some time
using channel ORA_DISK_1
analyzing automatic repair options complete

Mandatory Manual Actions
========================
no manual actions available

Optional Manual Actions
=======================
1. If you restored the wrong version of data file /u01/app/oracle/oradata/orcl/tbs04.dbf, then replace it with the correct one
2. If file /u01/app/oracle/oradata/orcl/tbs04.dbf was unintentionally renamed or moved, restore it

Automated Repair Options
========================
Option Repair Description
------ ------------------
1      Restore and recover datafile 13; Recover datafile 13 
  Strategy: The repair includes complete media recovery with no data loss
  Repair script: /u01/app/oracle/diag/rdbms/orcl/orcl/hm/reco_1931299378.hm

最后一行给出了恢复的脚本，查看脚本

[oracle@redhat6 ~]$ more /u01/app/oracle/diag/rdbms/orcl/orcl/hm/reco_1931299378.hm
   # restore and recover datafile
   sql 'alter database datafile 13 offline';
   restore datafile 13;
   recover datafile 13;
   sql 'alter database datafile 13 online';
   # recover datafile
   sql 'alter database datafile 13 offline';
   recover datafile 13;
   sql 'alter database datafile 13 online';

根据脚本，执行修复和恢复

RMAN>  sql 'alter database datafile 13 offline';

sql statement: alter database datafile 13 offline

RMAN> restore datafile 13;

Starting restore at 16-MAY-18
using channel ORA_DISK_1

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 00013 to /u01/app/oracle/oradata/orcl/tbs04.dbf
channel ORA_DISK_1: reading from backup piece /u01/app/oracle/product/11.2.0/db_1/dbs/01t31soh_1_1
channel ORA_DISK_1: piece handle=/u01/app/oracle/product/11.2.0/db_1/dbs/01t31soh_1_1 tag=TAG20180516T144121
channel ORA_DISK_1: restored backup piece 1
channel ORA_DISK_1: restore complete, elapsed time: 00:00:03
Finished restore at 16-MAY-18

RMAN> recover datafile 13;

Starting recover at 16-MAY-18
using channel ORA_DISK_1

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

Finished recover at 16-MAY-18

RMAN> sql 'alter database datafile 13 online';

sql statement: alter database datafile 13 online

（4）重启数据库，确认无异常

SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup
ORACLE instance started.

Total System Global Area  730714112 bytes
Fixed Size            2216944 bytes
Variable Size          314575888 bytes
Database Buffers      411041792 bytes
Redo Buffers            2879488 bytes
Database mounted.
Database opened.