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這篇文章主要講解了“Oracle12 RMAN 新特性 Recover Table 有什么作用”，文中的講解內(nèi)容簡(jiǎn)單清晰，易于學(xué)習(xí)與理解，下面請(qǐng)大家跟著丸趣 TV 小編的思路慢慢深入，一起來研究和學(xué)習(xí)“Oracle12 RMAN 新特性 Recover Table 有什么作用”吧！
在 Oracle 12c 之前，如果誤刪一張表，常規(guī)的方法是 Flashback 閃回或 TSPITR。而開啟 flashback 會(huì)消耗磁盤空間，且如果被 purge 或者經(jīng)過 DDL，將無法 flashback。如果需要恢復(fù)的表空間過大，TSPITR 會(huì)耗時(shí)非常久。12c 中提供了 Table Recovery 的新特性，可以針對(duì)單表（或單個(gè)表分區(qū)）基于時(shí)間點(diǎn)進(jìn)行恢復(fù)，該特性用以直接從 RMAN 備份中恢復(fù)表的方法，該特性有以下特點(diǎn)：
不影響數(shù)據(jù)庫中的其他數(shù)據(jù)庫對(duì)象
減少時(shí)間和磁盤空間的消耗，和早期的 TSPIRT 工作流程類似
從另一個(gè)磁盤路徑恢復(fù)表空間
導(dǎo)出想要的表數(shù)據(jù)
導(dǎo)入到原數(shù)據(jù)庫（可選）
recover table 可以將一個(gè)或多個(gè)表或表分區(qū)恢復(fù)到指定的時(shí)間點(diǎn)，而不會(huì)影響其余的數(shù)據(jù)庫對(duì)象。可以使用以前創(chuàng)建的 RMAN 備份將表和表分區(qū)恢復(fù)到指定的時(shí)間點(diǎn)。
該表被恢復(fù)到一個(gè)輔助實(shí)例中，并且可以選擇：
使用 REMAP 選項(xiàng)將恢復(fù)的表導(dǎo)入新表或分區(qū)
僅在恢復(fù)的表中創(chuàng)建 expdp dump 文件，以便在其他時(shí)間進(jìn)行導(dǎo)入
先決條件
目標(biāo)數(shù)據(jù)庫必須處于讀寫模式。
目標(biāo)數(shù)據(jù)庫必須處于 ARCHIVELOG 模式。
您必須擁有表或表分區(qū)的 RMAN 備份，因?yàn)樗鼈兇嬖谟谝謴?fù)這些對(duì)象的時(shí)間點(diǎn)。
要恢復(fù)單個(gè)表分區(qū)，目標(biāo)數(shù)據(jù)庫的 COMPATIBLE 初始化參數(shù)必須設(shè)置為 11.1.0 或更高。
請(qǐng)確保 AUXILIARY DESTINATION 有足夠的空間來恢復(fù) system、sysaux、undo 以及恢復(fù)表所需的表空間。
請(qǐng)注意，表恢復(fù)后，輔助目標(biāo)中的這些文件將自動(dòng)刪除
必須使用 AUXILIARY DESTINATION 子句和后面其中一個(gè)子句來指定恢復(fù)的時(shí)間點(diǎn)：UNTIL TIME、UNTIL SCN 或 UNTIL SEQUENCE。
使用限制
屬于 SYS 模式的表和表分區(qū)無法恢復(fù)。
SYSTEM 和 SYSAUX 表空間中的表和表分區(qū)無法恢復(fù)。
standby 數(shù)據(jù)庫上的表和表分區(qū)無法恢復(fù)。
命名為 NOT NULL 約束的表不能用 REMAP 選項(xiàng)恢復(fù)。
RMAN 從備份中自動(dòng)處理恢復(fù)表或者表分區(qū)時(shí)會(huì)執(zhí)行如下步驟：
1. 判斷哪些備份包含需要恢復(fù)的表或表分區(qū)，然后根據(jù)指定的時(shí)間來進(jìn)行恢復(fù)。
2. 判斷目標(biāo)主機(jī)上是否有足夠的空間來創(chuàng)建 auxiliary instance，該實(shí)例用于處理表或分區(qū)的恢復(fù)。如果需要的空間不足，那么 RMAN 會(huì)報(bào)錯(cuò)并退出恢復(fù)操作。
3. 創(chuàng)建 auxiliary database，并根據(jù)指定的時(shí)間來恢復(fù)指定的表或表分區(qū)到 auxiliary database 中。輔助數(shù)據(jù)庫的數(shù)據(jù)文件位置可以在命令中指定。
4. 創(chuàng)建包含恢復(fù)表或表分區(qū)的數(shù)據(jù)泵文件（expdp dump file）。數(shù)據(jù)泵的名稱和位置也可以在命令中指定。
5.（可選操作）將上一步生產(chǎn)的數(shù)據(jù)泵文件導(dǎo)入到目標(biāo)實(shí)例中。當(dāng)然也可以選擇不導(dǎo)入，如果選擇不導(dǎo)入就必須使用 impdp 手工導(dǎo)入。
6.（可選操作）在目標(biāo)數(shù)據(jù)庫中 rename 恢復(fù)表或表分區(qū)。
使用場(chǎng)景
RMAN 的表級(jí)和表分區(qū)級(jí)恢復(fù)在以下場(chǎng)景中非常適用：
（1） 需要將非常少量的表恢復(fù)至特定的時(shí)間點(diǎn)。在這種情況下，TSPITR 不是最有效的解決方案，因?yàn)樗鼤?huì)將表空間中的所有對(duì)象恢復(fù)到指定的時(shí)間點(diǎn)。
（2） 需要恢復(fù)已被邏輯損壞或已被
drop 和 purge
的表。
（3） flashback
不可用，比如需要的 undo 數(shù)據(jù)被覆蓋。
（4） DDL
操作修改表結(jié)構(gòu)后丟失的數(shù)據(jù)。flashback table 不能跨越 DDL（例如 truncate）來回滾表。
在這 Recover table 過程演示
創(chuàng)建測(cè)試表
SQL create table t_recover_test as select * from dba_objects;
Table created.
SQL select count(*) from t_recover_test;
COUNT(*)
———-
72652
備份
[oracle@localhost ~]$ rman target /
Recovery Manager: Release 12.2.0.1.0 – Production on Thu Jun 28 21:06:17 2018
Copyright (c) 1982, 2017, Oracle and/or its affiliates. All rights reserved.
connected to target database: PCC (DBID=3164878903)
RMAN
backup database format /home/oracle/bak/db_%U
Starting backup at 28-JUN-18
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=61 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=/home/oracle/oradata/pcc/system01.dbf
input datafile file number=00003 name=/home/oracle/oradata/pcc/sysaux01.dbf
input datafile file number=00004 name=/home/oracle/oradata/pcc/undotbs01.dbf
input datafile file number=00005 name=/home/oracle/oradata/pcc/tbs_zyq01.dbf
input datafile file number=00007 name=/home/oracle/oradata/pcc/users01.dbf
channel ORA_DISK_1: starting piece 1 at 28-JUN-18
channel ORA_DISK_1: finished piece 1 at 28-JUN-18
piece handle=/home/oracle/bak/db_01t6k254_1_1 tag=TAG20180628T215236 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:15
Finished backup at 28-JUN-18
Starting Control File and SPFILE Autobackup at 28-JUN-18
piece handle=/u01/app/oracle/product/12.2.0.1/dbs/c-3164878903-20180628-00 comment=NONE
Finished Control File and SPFILE Autobackup at 28-JUN-18
恢復(fù)表
[oracle@localhost ~]$ rman target /
Recovery Manager: Release 12.2.0.1.0 – Production on Fri Jun 29 00:52:29 2018
Copyright (c) 1982, 2017, Oracle and/or its affiliates. All rights reserved.
connected to target database: PCC (DBID=3164878903)
RMAN
RECOVER TABLE zyq.t_recover_test
until time to_date(2018-06-28 23:56:06 , yyyy-mm-dd hh34:mi:ss)
AUXILIARY DESTINATION /data01
REMAP TABLE zyq.t_recover_test:t_recover_test_map;
Starting recover at 29-JUN-18
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=66 device type=DISK
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= hCed
initialization parameters used for automatic instance:
db_name=PCC
db_unique_name=hCed_pitr_PCC
compatible=12.2.0
db_block_size=8192
db_files=200
diagnostic_dest=/u01/app/oracle
_system_trig_enabled=FALSE
sga_target=732M
processes=200
db_create_file_dest=/data01
log_archive_dest_1= location=/data01
#No auxiliary parameter file used
starting up automatic instance PCC
Oracle instance started
Total System Global Area 767557632 bytes
Fixed Size 8625416 bytes
Variable Size 213910264 bytes
Database Buffers 541065216 bytes
Redo Buffers 3956736 bytes
Automatic instance created
contents of Memory Script:
{
# set requested point in time
set until time to_date(2018-06-28 23:56:06 , yyyy-mm-dd hh34:mi:ss)
# 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 29-JUN-18
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=35 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/12.2.0.1/dbs/c-3164878903-20180628-01
channel ORA_AUX_DISK_1: piece handle=/u01/app/oracle/product/12.2.0.1/dbs/c-3164878903-20180628-01 tag=TAG20180628T234914
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:02
output file name=/data01/PCC/controlfile/o1_mf_fmcsc00p_.ctl
Finished restore at 29-JUN-18
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 time to_date(2018-06-28 23:56:06 , yyyy-mm-dd hh34:mi:ss)
# set destinations for recovery set and auxiliary set datafiles
set newname for clone datafile 1 to new;
set newname for clone datafile 4 to new;
set newname for clone datafile 3 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, 4, 3;
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 /data01/PCC/datafile/o1_mf_temp_%u_.tmp in control file
Starting restore at 29-JUN-18
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 /data01/PCC/datafile/o1_mf_system_%u_.dbf
channel ORA_AUX_DISK_1: restoring datafile 00004 to /data01/PCC/datafile/o1_mf_undotbs1_%u_.dbf
channel ORA_AUX_DISK_1: restoring datafile 00003 to /data01/PCC/datafile/o1_mf_sysaux_%u_.dbf
channel ORA_AUX_DISK_1: reading from backup piece /home/oracle/bak/db_01t6k254_1_1
channel ORA_AUX_DISK_1: piece handle=/home/oracle/bak/db_01t6k254_1_1 tag=TAG20180628T215236
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:15
Finished restore at 29-JUN-18
datafile 1 switched to datafile copy
input datafile copy RECID=4 STAMP=980038406 file name=/data01/PCC/datafile/o1_mf_system_fmcsc755_.dbf
datafile 4 switched to datafile copy
input datafile copy RECID=5 STAMP=980038406 file name=/data01/PCC/datafile/o1_mf_undotbs1_fmcsc75h_.dbf
datafile 3 switched to datafile copy
input datafile copy RECID=6 STAMP=980038406 file name=/data01/PCC/datafile/o1_mf_sysaux_fmcsc75c_.dbf
contents of Memory Script:
{
# set requested point in time
set until time to_date(2018-06-28 23:56:06 , yyyy-mm-dd hh34:mi:ss)
# online the datafiles restored or switched
sql clone alter database datafile 1 online
sql clone alter database datafile 4 online
sql clone alter database datafile 3 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 4 online
sql statement: alter database datafile 3 online
Starting recover at 29-JUN-18
using channel ORA_AUX_DISK_1
starting media recovery
archived log for thread 1 with sequence 3 is already on disk as file /u01/app/oracle/product/12.2.0.1/dbs/arch2_3_979872889.dbf
archived log for thread 1 with sequence 4 is already on disk as file /u01/app/oracle/product/12.2.0.1/dbs/arch2_4_979872889.dbf
archived log file name=/u01/app/oracle/product/12.2.0.1/dbs/arch2_3_979872889.dbf thread=1 sequence=3
archived log file name=/u01/app/oracle/product/12.2.0.1/dbs/arch2_4_979872889.dbf thread=1 sequence=4
media recovery complete, elapsed time: 00:00:11
Finished recover at 29-JUN-18
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 =
/data01/PCC/controlfile/o1_mf_fmcsc00p_.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 767557632 bytes
Fixed Size 8625416 bytes
Variable Size 213910264 bytes
Database Buffers 541065216 bytes
Redo Buffers 3956736 bytes
sql statement: alter system set control_files = /data01/PCC/controlfile/o1_mf_fmcsc00p_.ctl comment= RMAN set scope=spfile
Oracle instance shut down
connected to auxiliary database (not started)
Oracle instance started
Total System Global Area 767557632 bytes
Fixed Size 8625416 bytes
Variable Size 213910264 bytes
Database Buffers 541065216 bytes
Redo Buffers 3956736 bytes
sql statement: alter database mount clone database
contents of Memory Script:
{
# set requested point in time
set until time to_date(2018-06-28 23:56:06 , yyyy-mm-dd hh34:mi:ss)
# set destinations for recovery set and auxiliary set datafiles
set newname for datafile 5 to new;
# restore the tablespaces in the recovery set and the auxiliary set
restore clone datafile 5;
switch clone datafile all;
}
executing Memory Script
executing command: SET until clause
executing command: SET NEWNAME
Starting restore at 29-JUN-18
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=34 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 00005 to /data01/HCED_PITR_PCC/datafile/o1_mf_tbs_zyq_%u_.dbf
channel ORA_AUX_DISK_1: reading from backup piece /home/oracle/bak/db_01t6k254_1_1
channel ORA_AUX_DISK_1: piece handle=/home/oracle/bak/db_01t6k254_1_1 tag=TAG20180628T215236
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:03
Finished restore at 29-JUN-18
datafile 5 switched to datafile copy
input datafile copy RECID=8 STAMP=980038478 file name=/data01/HCED_PITR_PCC/datafile/o1_mf_tbs_zyq_fmcsfttn_.dbf
contents of Memory Script:
{
# set requested point in time
set until time to_date(2018-06-28 23:56:06 , yyyy-mm-dd hh34:mi:ss)
# online the datafiles restored or switched
sql clone alter database datafile 5 online
# recover and open resetlogs
recover clone database tablespace TBS_ZYQ , SYSTEM , UNDOTBS1 , SYSAUX delete archivelog;
alter clone database open resetlogs;
}
executing Memory Script
executing command: SET until clause
sql statement: alter database datafile 5 online
Starting recover at 29-JUN-18
using channel ORA_AUX_DISK_1
starting media recovery
archived log for thread 1 with sequence 3 is already on disk as file /u01/app/oracle/product/12.2.0.1/dbs/arch2_3_979872889.dbf
archived log for thread 1 with sequence 4 is already on disk as file /u01/app/oracle/product/12.2.0.1/dbs/arch2_4_979872889.dbf
archived log file name=/u01/app/oracle/product/12.2.0.1/dbs/arch2_3_979872889.dbf thread=1 sequence=3
archived log file name=/u01/app/oracle/product/12.2.0.1/dbs/arch2_4_979872889.dbf thread=1 sequence=4
media recovery complete, elapsed time: 00:00:01
Finished recover at 29-JUN-18
database opened
contents of Memory Script:
{
# create directory for datapump import
sql create or replace directory TSPITR_DIROBJ_DPDIR as
/data01
# create directory for datapump export
sql clone create or replace directory TSPITR_DIROBJ_DPDIR as
/data01
}
executing Memory Script
sql statement: create or replace directory TSPITR_DIROBJ_DPDIR as /data01
sql statement: create or replace directory TSPITR_DIROBJ_DPDIR as /data01
Performing export of tables…
EXPDP Starting SYS . TSPITR_EXP_hCed_Dhxe :
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/STATISTICS/MARKER
EXPDP Processing object type TABLE_EXPORT/TABLE/TABLE
EXPDP . . exported ZYQ . T_RECOVER_TEST 9.324 MB 72652 rows
EXPDP Master table SYS . TSPITR_EXP_hCed_Dhxe successfully loaded/unloaded
EXPDP ******************************************************************************
EXPDP Dump file set for SYS.TSPITR_EXP_hCed_Dhxe is:
EXPDP /data01/tspitr_hCed_71393.dmp
EXPDP Job SYS . TSPITR_EXP_hCed_Dhxe successfully completed at Fri Jun 29 00:55:41 2018 elapsed 0 00:00:35
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_hCed_Arhm successfully loaded/unloaded
IMPDP Starting SYS . TSPITR_IMP_hCed_Arhm :
IMPDP Processing object type TABLE_EXPORT/TABLE/TABLE
IMPDP Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
IMPDP . . imported ZYQ . T_RECOVER_TEST_MAP 9.324 MB 72652 rows
IMPDP Processing object type TABLE_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
IMPDP Processing object type TABLE_EXPORT/TABLE/STATISTICS/MARKER
IMPDP Job SYS . TSPITR_IMP_hCed_Arhm successfully completed at Fri Jun 29 00:56:43 2018 elapsed 0 00:00:45
Import completed
Removing automatic instance
Automatic instance removed
auxiliary instance file /data01/PCC/datafile/o1_mf_temp_fmcsd5ny_.tmp deleted
auxiliary instance file /data01/HCED_PITR_PCC/onlinelog/o1_mf_3_fmcsg3y6_.log deleted
auxiliary instance file /data01/HCED_PITR_PCC/onlinelog/o1_mf_2_fmcsg07o_.log deleted
auxiliary instance file /data01/HCED_PITR_PCC/onlinelog/o1_mf_1_fmcsfzr1_.log deleted
auxiliary instance file /data01/HCED_PITR_PCC/datafile/o1_mf_tbs_zyq_fmcsfttn_.dbf deleted
auxiliary instance file /data01/PCC/datafile/o1_mf_sysaux_fmcsc75c_.dbf deleted
auxiliary instance file /data01/PCC/datafile/o1_mf_undotbs1_fmcsc75h_.dbf deleted
auxiliary instance file /data01/PCC/datafile/o1_mf_system_fmcsc755_.dbf deleted
auxiliary instance file /data01/PCC/controlfile/o1_mf_fmcsc00p_.ctl deleted
auxiliary instance file tspitr_hCed_71393.dmp deleted
Finished recover at 29-JUN-18
RMAN
驗(yàn)證
SQL select count(*) from T_RECOVER_TEST_MAP;
COUNT(*)
———-
72652
感謝各位的閱讀，以上就是“Oracle12 RMAN 新特性 Recover Table 有什么作用”的內(nèi)容了，經(jīng)過本文的學(xué)習(xí)后，相信大家對(duì) Oracle12 RMAN 新特性 Recover Table 有什么作用這一問題有了更深刻的體會(huì)，具體使用情況還需要大家實(shí)踐驗(yàn)證。這里是丸趣 TV，丸趣 TV 小編將為大家推送更多相關(guān)知識(shí)點(diǎn)的文章，歡迎關(guān)注！
