在Oracle12c版本之前，使用RMAN能恢复的级别为数据库级别和表空间级别，如果只有一张表需要恢复，而在数据库级别或表空间级别做恢复，影响范围就太大了。因此12.2版本中提供了一个新特性使用RMAN在表级别做恢复，并且恢复过程中不影响数据库的正常使用。这一功能不仅可以恢复表，还可以恢复表分区。
To recover a table or table partition, you must have a full backup of undo, SYSTEM, SYSAUX, and the tablespace that contains the table or table partition.
使用recover table的一些限制条件：
When you use the RECOVER command to recover tables or table partitions contained in an RMAN backup, the following limitations exist.
Tables and table partitions belonging to
SYSschema cannot be recovered.Tables and table partitions from
SYSTEMandSYSAUXtablespaces cannot be recovered.Tables and table partitions on standby databases cannot be recovered.
Tables with named
NOT NULLconstraints cannot be recovered with theREMAPoption.
下面在12.2版本上做表级别恢复的实验
sys@ORA12C>select * from v$version; BANNER CON_ID -------------------------------------------------------------------------------- ---------- Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production 0 PL/SQL Release 12.2.0.1.0 - Production 0 CORE 12.2.0.1.0 Production 0 TNS for Linux: Version 12.2.0.1.0 - Production 0 NLSRTL Version 12.2.0.1.0 - Production 0
1、创建一个数据库的全备
RMAN> backup database; Starting backup at 20170720 17:12:05 using target database control file instead of recovery catalog allocated channel: ORA_DISK_1 channel ORA_DISK_1: SID=36 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=+DATA/ORA12C/DATAFILE/system.256.949764433 channel ORA_DISK_1: starting piece 1 at 20170720 17:12:07 channel ORA_DISK_1: finished piece 1 at 20170720 17:12:22 piece handle=/u01/app/oracle/product/12.2/db_home1/dbs/0vs9rar7_1_1 tag=TAG20170720T171206 comment=NONE channel ORA_DISK_1: backup set complete, elapsed time: 00:00:15 channel ORA_DISK_1: starting full datafile backup set channel ORA_DISK_1: specifying datafile(s) in backup set input datafile file number=00004 name=+DATA/ORA12C/DATAFILE/users.266.949764465 channel ORA_DISK_1: starting piece 1 at 20170720 17:12:22 channel ORA_DISK_1: finished piece 1 at 20170720 17:12:23 piece handle=/u01/app/oracle/product/12.2/db_home1/dbs/10s9rarm_1_1 tag=TAG20170720T171206 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 input datafile file number=00002 name=+DATA/ORA12C/DATAFILE/sysaux.261.949764491 channel ORA_DISK_1: starting piece 1 at 20170720 17:12:23 channel ORA_DISK_1: finished piece 1 at 20170720 17:12:38 piece handle=/u01/app/oracle/product/12.2/db_home1/dbs/11s9rarn_1_1 tag=TAG20170720T171206 comment=NONE channel ORA_DISK_1: backup set complete, elapsed time: 00:00:15 channel ORA_DISK_1: starting full datafile backup set channel ORA_DISK_1: specifying datafile(s) in backup set input datafile file number=00005 name=+DATA/ORA12C/DATAFILE/examples.265.949764515 channel ORA_DISK_1: starting piece 1 at 20170720 17:12:38 channel ORA_DISK_1: finished piece 1 at 20170720 17:12:39 piece handle=/u01/app/oracle/product/12.2/db_home1/dbs/12s9ras6_1_1 tag=TAG20170720T171206 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 input datafile file number=00008 name=/tmp/FY_RST_DATA.DAT input datafile file number=00007 name=/tmp/FY_REC_DATA.DAT input datafile file number=00003 name=+DATA/ORA12C/DATAFILE/undotbs1.264.949764541 input datafile file number=00006 name=+DATA/ORA12C/DATAFILE/t_move.dbf channel ORA_DISK_1: starting piece 1 at 20170720 17:12:40 channel ORA_DISK_1: finished piece 1 at 20170720 17:12:41 piece handle=/u01/app/oracle/product/12.2/db_home1/dbs/13s9ras8_1_1 tag=TAG20170720T171206 comment=NONE channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01 Finished backup at 20170720 17:12:41 Starting Control File and SPFILE Autobackup at 20170720 17:12:41 piece handle=/u01/app/oracle/product/12.2/db_home1/dbs/c-326793150-20170720-00 comment=NONE Finished Control File and SPFILE Autobackup at 20170720 17:12:42
2、创建测试表，插入测试数据并记录中间的scn号
zx@ORA12C>create table t2 (id number,name varchar2(10),birthday date); Table created. zx@ORA12C>insert into t2 values(1,'zx',sysdate); 1 row created. zx@ORA12C>commit; Commit complete. zx@ORA12C>select current_scn from v$database; CURRENT_SCN ----------- 650101 zx@ORA12C>insert into t2 values(2,'lx',sysdate); 1 row created. zx@ORA12C>commit; Commit complete. zx@ORA12C>select * from t2; ID NAME BIRTHDAY ---------- ---------- ----------------- 1 zx 20170720 17:18:52 2 lx 20170720 17:19:34
3、执行表级别恢复，使用remap table参数不覆盖原表，恢复成t2_r表
RMAN> recover table zx.t2 until scn 650101 remap table zx.t2:t2_r auxiliary destination '/tmp';
Starting recover at 20170720 17:23:50
current log archived
using channel ORA_DISK_1
RMAN-05026: warning: presuming following set of tablespaces applies to specified point-in-time
List of tablespaces expected to have UNDO segments
Tablespace SYSTEM
Tablespace UNDOTBS1
Creating automatic instance, with SID='htzD'
initialization parameters used for automatic instance:
db_name=ORA12C
db_unique_name=htzD_pitr_ORA12C
compatible=12.2.0
db_block_size=8192
db_files=200
diagnostic_dest=/u01/app/oracle
_system_trig_enabled=FALSE
sga_target=1712M
processes=200
db_create_file_dest=/tmp
log_archive_dest_1='location=/tmp'
#No auxiliary parameter file used
starting up automatic instance ORA12C
Oracle instance started
Total System Global Area 1795162112 bytes
Fixed Size 8621760 bytes
Variable Size 436207936 bytes
Database Buffers 1342177280 bytes
Redo Buffers 8155136 bytes
Automatic instance created
contents of Memory Script:
{
# set requested point in time
set until scn 650101;
# restore the controlfile
restore clone controlfile;
# mount the controlfile
sql clone 'alter database mount clone database';
# archive current online log
sql 'alter system archive log current';
}
executing Memory Script
executing command: SET until clause
Starting restore at 20170720 17:24:12
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=18 device type=DISK
channel ORA_AUX_DISK_1: starting datafile backup set restore
channel ORA_AUX_DISK_1: restoring control file
channel ORA_AUX_DISK_1: reading from backup piece /u01/app/oracle/product/12.2/db_home1/dbs/c-326793150-20170720-00
channel ORA_AUX_DISK_1: piece handle=/u01/app/oracle/product/12.2/db_home1/dbs/c-326793150-20170720-00 tag=TAG20170720T171241
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:01
output file name=/tmp/ORA12C/controlfile/o1_mf_dq0xoxot_.ctl
Finished restore at 20170720 17:24:14
sql statement: alter database mount clone database
sql statement: alter system archive log current
contents of Memory Script:
{
# set requested point in time
set until scn 650101;
# set destinations for recovery set and auxiliary set datafiles
set newname for clone datafile 1 to new;
set newname for clone datafile 3 to new;
set newname for clone datafile 2 to new;
set newname for clone tempfile 1 to new;
# switch all tempfiles
switch clone tempfile all;
# restore the tablespaces in the recovery set and the auxiliary set
restore clone datafile 1, 3, 2;
switch clone datafile all;
}
executing Memory Script
executing command: SET until clause
executing command: SET NEWNAME
executing command: SET NEWNAME
executing command: SET NEWNAME
executing command: SET NEWNAME
renamed tempfile 1 to /tmp/ORA12C/datafile/o1_mf_temp_%u_.tmp in control file
Starting restore at 20170720 17:24:19
using channel ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: starting datafile backup set restore
channel ORA_AUX_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_AUX_DISK_1: restoring datafile 00001 to /tmp/ORA12C/datafile/o1_mf_system_%u_.dbf
channel ORA_AUX_DISK_1: reading from backup piece /u01/app/oracle/product/12.2/db_home1/dbs/0vs9rar7_1_1
channel ORA_AUX_DISK_1: piece handle=/u01/app/oracle/product/12.2/db_home1/dbs/0vs9rar7_1_1 tag=TAG20170720T171206
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:45
channel ORA_AUX_DISK_1: starting datafile backup set restore
channel ORA_AUX_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_AUX_DISK_1: restoring datafile 00002 to /tmp/ORA12C/datafile/o1_mf_sysaux_%u_.dbf
channel ORA_AUX_DISK_1: reading from backup piece /u01/app/oracle/product/12.2/db_home1/dbs/11s9rarn_1_1
channel ORA_AUX_DISK_1: piece handle=/u01/app/oracle/product/12.2/db_home1/dbs/11s9rarn_1_1 tag=TAG20170720T171206
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:35
channel ORA_AUX_DISK_1: starting datafile backup set restore
channel ORA_AUX_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_AUX_DISK_1: restoring datafile 00003 to /tmp/ORA12C/datafile/o1_mf_undotbs1_%u_.dbf
channel ORA_AUX_DISK_1: reading from backup piece /u01/app/oracle/product/12.2/db_home1/dbs/13s9ras8_1_1
channel ORA_AUX_DISK_1: piece handle=/u01/app/oracle/product/12.2/db_home1/dbs/13s9ras8_1_1 tag=TAG20170720T171206
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:15
Finished restore at 20170720 17:25:55
datafile 1 switched to datafile copy
input datafile copy RECID=16 STAMP=949857956 file name=/tmp/ORA12C/datafile/o1_mf_system_dq0xp4jt_.dbf
datafile 3 switched to datafile copy
input datafile copy RECID=17 STAMP=949857956 file name=/tmp/ORA12C/datafile/o1_mf_undotbs1_dq0xrnq2_.dbf
datafile 2 switched to datafile copy
input datafile copy RECID=18 STAMP=949857956 file name=/tmp/ORA12C/datafile/o1_mf_sysaux_dq0xqkm0_.dbf
contents of Memory Script:
{
# set requested point in time
set until scn 650101;
# online the datafiles restored or switched
sql clone "alter database datafile 1 online";
sql clone "alter database datafile 3 online";
sql clone "alter database datafile 2 online";
# recover and open database read only
recover clone database tablespace "SYSTEM", "UNDOTBS1", "SYSAUX";
sql clone 'alter database open read only';
}
executing Memory Script
executing command: SET until clause
sql statement: alter database datafile 1 online
sql statement: alter database datafile 3 online
sql statement: alter database datafile 2 online
Starting recover at 20170720 17:26:02
using channel ORA_AUX_DISK_1
starting media recovery
archived log for thread 1 with sequence 2 is already on disk as file /u01/app/oracle/product/12.2/db_home1/dbs/arch1_2_949077789.dbf
archived log for thread 1 with sequence 3 is already on disk as file /u01/app/oracle/product/12.2/db_home1/dbs/arch1_3_949077789.dbf
archived log file name=/u01/app/oracle/product/12.2/db_home1/dbs/arch1_2_949077789.dbf thread=1 sequence=2
archived log file name=/u01/app/oracle/product/12.2/db_home1/dbs/arch1_3_949077789.dbf thread=1 sequence=3
media recovery complete, elapsed time: 00:00:02
Finished recover at 20170720 17:26:07
sql statement: alter database open read only
contents of Memory Script:
{
sql clone "create spfile from memory";
shutdown clone immediate;
startup clone nomount;
sql clone "alter system set control_files =
''/tmp/ORA12C/controlfile/o1_mf_dq0xoxot_.ctl'' comment=
''RMAN set'' scope=spfile";
shutdown clone immediate;
startup clone nomount;
# mount database
sql clone 'alter database mount clone database';
}
executing Memory Script
sql statement: create spfile from memory
database closed
database dismounted
Oracle instance shut down
connected to auxiliary database (not started)
Oracle instance started
Total System Global Area 1795162112 bytes
Fixed Size 8621760 bytes
Variable Size 436207936 bytes
Database Buffers 1342177280 bytes
Redo Buffers 8155136 bytes
sql statement: alter system set control_files = ''/tmp/ORA12C/controlfile/o1_mf_dq0xoxot_.ctl'' comment= ''RMAN set'' scope=spfile
Oracle instance shut down
connected to auxiliary database (not started)
Oracle instance started
Total System Global Area 1795162112 bytes
Fixed Size 8621760 bytes
Variable Size 436207936 bytes
Database Buffers 1342177280 bytes
Redo Buffers 8155136 bytes
sql statement: alter database mount clone database
contents of Memory Script:
{
# set requested point in time
set until scn 650101;
# set destinations for recovery set and auxiliary set datafiles
set newname for datafile 4 to new;
# restore the tablespaces in the recovery set and the auxiliary set
restore clone datafile 4;
switch clone datafile all;
}
executing Memory Script
executing command: SET until clause
executing command: SET NEWNAME
Starting restore at 20170720 17:27:18
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=23 device type=DISK
channel ORA_AUX_DISK_1: starting datafile backup set restore
channel ORA_AUX_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_AUX_DISK_1: restoring datafile 00004 to /tmp/HTZD_PITR_ORA12C/datafile/o1_mf_users_%u_.dbf
channel ORA_AUX_DISK_1: reading from backup piece /u01/app/oracle/product/12.2/db_home1/dbs/10s9rarm_1_1
channel ORA_AUX_DISK_1: piece handle=/u01/app/oracle/product/12.2/db_home1/dbs/10s9rarm_1_1 tag=TAG20170720T171206
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:25
Finished restore at 20170720 17:27:44
datafile 4 switched to datafile copy
input datafile copy RECID=20 STAMP=949858064 file name=/tmp/HTZD_PITR_ORA12C/datafile/o1_mf_users_dq0xvq9q_.dbf
contents of Memory Script:
{
# set requested point in time
set until scn 650101;
# online the datafiles restored or switched
sql clone "alter database datafile 4 online";
# recover and open resetlogs
recover clone database tablespace "USERS", "SYSTEM", "UNDOTBS1", "SYSAUX" delete archivelog;
alter clone database open resetlogs;
}
executing Memory Script
executing command: SET until clause
sql statement: alter database datafile 4 online
Starting recover at 20170720 17:27:44
using channel ORA_AUX_DISK_1
starting media recovery
archived log for thread 1 with sequence 2 is already on disk as file /u01/app/oracle/product/12.2/db_home1/dbs/arch1_2_949077789.dbf
archived log for thread 1 with sequence 3 is already on disk as file /u01/app/oracle/product/12.2/db_home1/dbs/arch1_3_949077789.dbf
archived log file name=/u01/app/oracle/product/12.2/db_home1/dbs/arch1_2_949077789.dbf thread=1 sequence=2
archived log file name=/u01/app/oracle/product/12.2/db_home1/dbs/arch1_3_949077789.dbf thread=1 sequence=3
media recovery complete, elapsed time: 00:00:01
Finished recover at 20170720 17:27:48
database opened
contents of Memory Script:
{
# create directory for datapump import
sql "create or replace directory TSPITR_DIROBJ_DPDIR as ''
/tmp''";
# create directory for datapump export
sql clone "create or replace directory TSPITR_DIROBJ_DPDIR as ''
/tmp''";
}
executing Memory Script
sql statement: create or replace directory TSPITR_DIROBJ_DPDIR as ''/tmp''
sql statement: create or replace directory TSPITR_DIROBJ_DPDIR as ''/tmp''
Performing export of tables...
EXPDP> Starting "SYS"."TSPITR_EXP_htzD_mhEh":
EXPDP> Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
EXPDP> Processing object type TABLE_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
EXPDP> Processing object type TABLE_EXPORT/TABLE/TABLE
EXPDP> . . exported "ZX"."T2" 5.898 KB 1 rows
EXPDP> Master table "SYS"."TSPITR_EXP_htzD_mhEh" successfully loaded/unloaded
EXPDP> ******************************************************************************
EXPDP> Dump file set for SYS.TSPITR_EXP_htzD_mhEh is:
EXPDP> /tmp/tspitr_htzD_98436.dmp
EXPDP> Job "SYS"."TSPITR_EXP_htzD_mhEh" successfully completed at Thu Jul 20 17:29:48 2017 elapsed 0 00:01:05
Export completed
contents of Memory Script:
{
# shutdown clone before import
shutdown clone abort
}
executing Memory Script
Oracle instance shut down
Performing import of tables...
IMPDP> Master table "SYS"."TSPITR_IMP_htzD_bhqf" successfully loaded/unloaded
IMPDP> Starting "SYS"."TSPITR_IMP_htzD_bhqf":
IMPDP> Processing object type TABLE_EXPORT/TABLE/TABLE
IMPDP> Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
IMPDP> . . imported "ZX"."T2_R" 5.898 KB 1 rows
IMPDP> Processing object type TABLE_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
IMPDP> Job "SYS"."TSPITR_IMP_htzD_bhqf" successfully completed at Thu Jul 20 17:30:10 2017 elapsed 0 00:00:10
Import completed
Removing automatic instance
Automatic instance removed
auxiliary instance file /tmp/ORA12C/datafile/o1_mf_temp_dq0xskvm_.tmp deleted
auxiliary instance file /tmp/HTZD_PITR_ORA12C/onlinelog/o1_mf_3_dq0xwo3d_.log deleted
auxiliary instance file /tmp/HTZD_PITR_ORA12C/onlinelog/o1_mf_2_dq0xwo3d_.log deleted
auxiliary instance file /tmp/HTZD_PITR_ORA12C/onlinelog/o1_mf_1_dq0xwo0q_.log deleted
auxiliary instance file /tmp/HTZD_PITR_ORA12C/datafile/o1_mf_users_dq0xvq9q_.dbf deleted
auxiliary instance file /tmp/ORA12C/datafile/o1_mf_sysaux_dq0xqkm0_.dbf deleted
auxiliary instance file /tmp/ORA12C/datafile/o1_mf_undotbs1_dq0xrnq2_.dbf deleted
auxiliary instance file /tmp/ORA12C/datafile/o1_mf_system_dq0xp4jt_.dbf deleted
auxiliary instance file /tmp/ORA12C/controlfile/o1_mf_dq0xoxot_.ctl deleted
auxiliary instance file tspitr_htzD_98436.dmp deleted
Finished recover at 20170720 17:30:13
4、验证结果，查询t2_r表
zx@ORA12C>select * from t2_r; ID NAME BIRTHDAY ---------- ---------- ----------------- 1 zx 20170720 17:18:52
5、即使表t2做了DDL操作修改了表结构，也可以用这种方法进行恢复
--表t2添加一个字段 zx@ORA12C>alter table t2 add address varchar2(10); Table altered. --恢复表到t2_r2 RMAN> recover table zx.t2 until scn 650101 remap table zx.t2:t2_r2 auxiliary destination '/tmp'; Starting recover at 20170720 17:57:00 using channel ORA_DISK_1 RMAN-05026: warning: presuming following set of tablespaces applies to specified point-in-time ...... Finished recover at 20170720 18:02:03 --验证表t2_r2 zx@ORA12C>select * from t2_r2; ID NAME BIRTHDAY ---------- ---------- ----------------- 1 zx 20170720 17:18:52 --恢复成功
这一功能很大程度减小了数据恢复的影响范围。
参考：http://docs.oracle.com/database/121/BRADV/rcmresind.htm#BRADV686