RMANTablePointInTimeRecovery(PITR)inPDBs
p
1.首先使用RMAN做一次备份(必需有次备份) rman target / backup database; or backup database root; backup pluggable database pdb; 2.在pdb中创建test用户并授权 sqlplus / as sysdba alter session set container=pdb; create user test identified by r
1.首先使用RMAN做一次备份(必需有次备份)
rman target /
backup database;
or
backup database root;
backup pluggable database pdb;
2.在pdb中创建test用户并授权
sqlplus / as sysdba
alter session set container=pdb;
create user test identified by redhat quota unlimited on users;
grant connect,create table to test;
3.用测试用户创建测试表并查询当前scn
create table t1 (id int);
insert into t1 values(1);
commit;
SQL> select * from t1;
ID
----------
1
conn / as sysdba
SQL> SELECT DBMS_FLASHBACK.get_system_change_number FROM dual;
GET_SYSTEM_CHANGE_NUMBER
------------------------
1970004
4.再往t1表中插入一条数据
sqlplus test/redhat@pdb
SQL> insert into t1 values(2);
1 row created.
SQL> commit;
Commit complete.
SQL> select * from t1;
ID
----------
1
2
5.使用RMAN来恢复
rman target /
RECOVER TABLE 'TEST'.'T1' OF PLUGGABLE DATABASE pdb
UNTIL SCN 1970004
AUXILIARY DESTINATION '/u01/aux'
REMAP TABLE 'TEST'.'T1':'T1_old';
or
RECOVER TABLE 'TEST'.'T1' OF PLUGGABLE DATABASE pdb
UNTIL SCN 1970004
AUXILIARY DESTINATION '/u01/aux'
DATAPUMP DESTINATION '/u01/export'
DUMP FILE 'test_t1_old.dmp'--将以前的数据expdp出来
NOTABLEIMPORT;--不会将之前的数据导入
6.查询恢复过来的表t1_old验证恢复的内容
sqlplus test/redhat@pdb
SQL> select * from t1_old;
ID
----------
1
SQL> select * from t1;
ID
----------
1
2
7.总结
此功能效果和flashback table差不多
alter table t1 enable row movement;
先将t1备份
create table t1_bak as select * from t1;
flashback table t1 to scn 1970004;--基于SCN闪回
flashback table t1 to timestamp to_timestamp('2014-06-07 14:41:19','yyyy-mm-dd hh24:mi:ss'); --基于时间戳闪回
8.下面是日志
[oracle@source admin]$ rman target /
Recovery Manager: Release 12.1.0.1.0 - Production on Sat Jun 7 14:42:27 2014
Copyright (c) 1982, 2013, Oracle and/or its affiliates. All rights reserved.
connected to target database: CDB1 (DBID=823327692)
RMAN> RECOVER TABLE 'TEST'.'T1' OF PLUGGABLE DATABASE pdb
UNTIL SCN 1970004
AUXILIARY DESTINATION '/u01/aux'
REMAP TABLE 'TEST'.'T1':'T1_OLD';2> 3> 4>
Starting recover at 07-JUN-14
using target database control file instead of recovery catalog
current log archived
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=269 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='peCr'
initialization parameters used for automatic instance:
db_name=CDB1
db_unique_name=peCr_pitr_pdb_CDB1
compatible=12.1.0.0.0
db_block_size=8192
db_files=200
sga_target=1G
processes=80
diagnostic_dest=/u01/app/oracle
db_create_file_dest=/u01/aux
log_archive_dest_1='location=/u01/aux'
enable_pluggable_database=true
_clone_one_pdb_recovery=true
#No auxiliary parameter file used
starting up automatic instance CDB1
Oracle instance started
Total System Global Area 1068937216 bytes
Fixed Size 2296576 bytes
Variable Size 281019648 bytes
Database Buffers 780140544 bytes
Redo Buffers 5480448 bytes
Automatic instance created
contents of Memory Script:
{
# set requested point in time
set until scn 1970004;
# 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 07-JUN-14
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=75 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/recovery_area/CDB1/autobackup/2014_06_07/o1_mf_s_849623963_9s5dwvr3_.bkp
channel ORA_AUX_DISK_1: piece handle=/u01/app/oracle/recovery_area/CDB1/autobackup/2014_06_07/o1_mf_s_849623963_9s5dwvr3_.bkp tag=TAG20140607T143923
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:01
output file name=/u01/aux/CDB1/controlfile/o1_mf_9s5f3180_.ctl
Finished restore at 07-JUN-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 1970004;
# 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 datafile 8 to new;
set newname for clone datafile 9 to new;
set newname for clone tempfile 1 to new;
set newname for clone tempfile 3 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, 8, 9;
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
executing command: SET NEWNAME
executing command: SET NEWNAME
executing command: SET NEWNAME
renamed tempfile 1 to /u01/aux/CDB1/datafile/o1_mf_temp_%u_.tmp in control file
renamed tempfile 3 to /u01/aux/CDB1/datafile/o1_mf_temp_%u_.tmp in control file
Starting restore at 07-JUN-14
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 /u01/aux/CDB1/datafile/o1_mf_system_%u_.dbf
channel ORA_AUX_DISK_1: restoring datafile 00004 to /u01/aux/CDB1/datafile/o1_mf_undotbs1_%u_.dbf
channel ORA_AUX_DISK_1: restoring datafile 00003 to /u01/aux/CDB1/datafile/o1_mf_sysaux_%u_.dbf
channel ORA_AUX_DISK_1: reading from backup piece /u01/app/oracle/recovery_area/CDB1/backupset/2014_06_07/o1_mf_nnndf_TAG20140607T143730_9s5dsblv_.bkp
channel ORA_AUX_DISK_1: piece handle=/u01/app/oracle/recovery_area/CDB1/backupset/2014_06_07/o1_mf_nnndf_TAG20140607T143730_9s5dsblv_.bkp tag=TAG20140607T143730
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:55
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 00008 to /u01/aux/CDB1/datafile/o1_mf_system_%u_.dbf
channel ORA_AUX_DISK_1: restoring datafile 00009 to /u01/aux/CDB1/datafile/o1_mf_sysaux_%u_.dbf
channel ORA_AUX_DISK_1: reading from backup piece /u01/app/oracle/recovery_area/CDB1/FB373ED0C69817BBE0436405A8C0E168/backupset/2014_06_07/o1_mf_nnndf_TAG20140607T143848_9s5dvrc5_.bkp
channel ORA_AUX_DISK_1: piece handle=/u01/app/oracle/recovery_area/CDB1/FB373ED0C69817BBE0436405A8C0E168/backupset/2014_06_07/o1_mf_nnndf_TAG20140607T143848_9s5dvrc5_.bkp tag=TAG20140607T143848
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:36
Finished restore at 07-JUN-14
datafile 1 switched to datafile copy
input datafile copy RECID=8 STAMP=849624258 file name=/u01/aux/CDB1/datafile/o1_mf_system_9s5f37pd_.dbf
datafile 4 switched to datafile copy
input datafile copy RECID=9 STAMP=849624258 file name=/u01/aux/CDB1/datafile/o1_mf_undotbs1_9s5f37py_.dbf
datafile 3 switched to datafile copy
input datafile copy RECID=10 STAMP=849624258 file name=/u01/aux/CDB1/datafile/o1_mf_sysaux_9s5f37pt_.dbf
datafile 8 switched to datafile copy
input datafile copy RECID=11 STAMP=849624258 file name=/u01/aux/CDB1/datafile/o1_mf_system_9s5f4zb5_.dbf
datafile 9 switched to datafile copy
input datafile copy RECID=12 STAMP=849624258 file name=/u01/aux/CDB1/datafile/o1_mf_sysaux_9s5f4z79_.dbf
contents of Memory Script:
{
# set requested point in time
set until scn 1970004;
# 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";
sql clone 'PDB' "alter database datafile
8 online";
sql clone 'PDB' "alter database datafile
9 online";
# recover and open database read only
recover clone database tablespace "SYSTEM", "UNDOTBS1", "SYSAUX", "PDB":"SYSTEM", "PDB":"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
sql statement: alter database datafile 8 online
sql statement: alter database datafile 9 online
Starting recover at 07-JUN-14
using channel ORA_AUX_DISK_1
starting media recovery
archived log for thread 1 with sequence 27 is already on disk as file /u01/app/oracle/recovery_area/CDB1/archivelog/2014_06_07/o1_mf_1_27_9s5f2pgz_.arc
archived log file name=/u01/app/oracle/recovery_area/CDB1/archivelog/2014_06_07/o1_mf_1_27_9s5f2pgz_.arc thread=1 sequence=27
media recovery complete, elapsed time: 00:00:01
Finished recover at 07-JUN-14
sql statement: alter database open read only
contents of Memory Script:
{
sql clone 'alter pluggable database PDB open read only';
}
executing Memory Script
sql statement: alter pluggable database PDB 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 =
''/u01/aux/CDB1/controlfile/o1_mf_9s5f3180_.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 1068937216 bytes
Fixed Size 2296576 bytes
Variable Size 285213952 bytes
Database Buffers 775946240 bytes
Redo Buffers 5480448 bytes
sql statement: alter system set control_files = ''/u01/aux/CDB1/controlfile/o1_mf_9s5f3180_.ctl'' comment= ''RMAN set'' scope=spfile
Oracle instance shut down
connected to auxiliary database (not started)
Oracle instance started
Total System Global Area 1068937216 bytes
Fixed Size 2296576 bytes
Variable Size 285213952 bytes
Database Buffers 775946240 bytes
Redo Buffers 5480448 bytes
sql statement: alter database mount clone database
contents of Memory Script:
{
# set requested point in time
set until scn 1970004;
# set destinations for recovery set and auxiliary set datafiles
set newname for datafile 10 to new;
# restore the tablespaces in the recovery set and the auxiliary set
restore clone datafile 10;
switch clone datafile all;
}
executing Memory Script
executing command: SET until clause
executing command: SET NEWNAME
Starting restore at 07-JUN-14
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=11 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 00010 to /u01/aux/PECR_PITR_PDB_CDB1/datafile/o1_mf_users_%u_.dbf
channel ORA_AUX_DISK_1: reading from backup piece /u01/app/oracle/recovery_area/CDB1/FB373ED0C69817BBE0436405A8C0E168/backupset/2014_06_07/o1_mf_nnndf_TAG20140607T143848_9s5dvrc5_.bkp
channel ORA_AUX_DISK_1: piece handle=/u01/app/oracle/recovery_area/CDB1/FB373ED0C69817BBE0436405A8C0E168/backupset/2014_06_07/o1_mf_nnndf_TAG20140607T143848_9s5dvrc5_.bkp tag=TAG20140607T143848
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:01
Finished restore at 07-JUN-14
datafile 10 switched to datafile copy
input datafile copy RECID=14 STAMP=849624303 file name=/u01/aux/PECR_PITR_PDB_CDB1/datafile/o1_mf_users_9s5f7gol_.dbf
contents of Memory Script:
{
# set requested point in time
set until scn 1970004;
# online the datafiles restored or switched
sql clone 'PDB' "alter database datafile
10 online";
# recover and open resetlogs
recover clone database tablespace "PDB":"USERS", "SYSTEM", "UNDOTBS1", "SYSAUX", "PDB":"SYSTEM", "PDB":"SYSAUX" delete archivelog;
alter clone database open resetlogs;
}
executing Memory Script
executing command: SET until clause
sql statement: alter database datafile 10 online
Starting recover at 07-JUN-14
using channel ORA_AUX_DISK_1
starting media recovery
archived log for thread 1 with sequence 27 is already on disk as file /u01/app/oracle/recovery_area/CDB1/archivelog/2014_06_07/o1_mf_1_27_9s5f2pgz_.arc
archived log file name=/u01/app/oracle/recovery_area/CDB1/archivelog/2014_06_07/o1_mf_1_27_9s5f2pgz_.arc thread=1 sequence=27
media recovery complete, elapsed time: 00:00:00
Finished recover at 07-JUN-14
database opened
contents of Memory Script:
{
sql clone 'alter pluggable database PDB open';
}
executing Memory Script
sql statement: alter pluggable database PDB open
contents of Memory Script:
{
# create directory for datapump import
sql 'PDB' "create or replace directory
TSPITR_DIROBJ_DPDIR as ''
/u01/aux''";
# create directory for datapump export
sql clone 'PDB' "create or replace directory
TSPITR_DIROBJ_DPDIR as ''
/u01/aux''";
}
executing Memory Script
sql statement: create or replace directory TSPITR_DIROBJ_DPDIR as ''/u01/aux''
sql statement: create or replace directory TSPITR_DIROBJ_DPDIR as ''/u01/aux''
Performing export of tables...
EXPDP> Starting "SYS"."TSPITR_EXP_peCr_crua":
EXPDP> Estimate in progress using BLOCKS method...
EXPDP> Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
EXPDP> Total estimation using BLOCKS method: 64 KB
EXPDP> Processing object type TABLE_EXPORT/TABLE/TABLE
EXPDP> Processing object type TABLE_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
EXPDP> Processing object type TABLE_EXPORT/TABLE/STATISTICS/MARKER
EXPDP> . . exported "TEST"."T1" 5.039 KB 1 rows
EXPDP> Master table "SYS"."TSPITR_EXP_peCr_crua" successfully loaded/unloaded
EXPDP> ******************************************************************************
EXPDP> Dump file set for SYS.TSPITR_EXP_peCr_crua is:
EXPDP> /u01/aux/tspitr_peCr_89262.dmp
EXPDP> Job "SYS"."TSPITR_EXP_peCr_crua" successfully completed at Sat Jun 7 14:46:09 2014 elapsed 0 00:00:29
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_peCr_xgeA" successfully loaded/unloaded
IMPDP> Starting "SYS"."TSPITR_IMP_peCr_xgeA":
IMPDP> Processing object type TABLE_EXPORT/TABLE/TABLE
IMPDP> Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
IMPDP> . . imported "TEST"."T1_OLD" 5.039 KB 1 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_peCr_xgeA" successfully completed at Sat Jun 7 14:46:15 2014 elapsed 0 00:00:02
Import completed
Removing automatic instance
Automatic instance removed
auxiliary instance file /u01/aux/CDB1/datafile/o1_mf_temp_9s5f6jdq_.tmp deleted
auxiliary instance file /u01/aux/CDB1/datafile/o1_mf_temp_9s5f66jr_.tmp deleted
auxiliary instance file /u01/aux/PECR_PITR_PDB_CDB1/onlinelog/o1_mf_3_9s5f7m7c_.log deleted
auxiliary instance file /u01/aux/PECR_PITR_PDB_CDB1/onlinelog/o1_mf_2_9s5f7l9n_.log deleted
auxiliary instance file /u01/aux/PECR_PITR_PDB_CDB1/onlinelog/o1_mf_1_9s5f7jps_.log deleted
auxiliary instance file /u01/aux/PECR_PITR_PDB_CDB1/datafile/o1_mf_users_9s5f7gol_.dbf deleted
auxiliary instance file /u01/aux/CDB1/datafile/o1_mf_sysaux_9s5f4z79_.dbf deleted
auxiliary instance file /u01/aux/CDB1/datafile/o1_mf_system_9s5f4zb5_.dbf deleted
auxiliary instance file /u01/aux/CDB1/datafile/o1_mf_sysaux_9s5f37pt_.dbf deleted
auxiliary instance file /u01/aux/CDB1/datafile/o1_mf_undotbs1_9s5f37py_.dbf deleted
auxiliary instance file /u01/aux/CDB1/datafile/o1_mf_system_9s5f37pd_.dbf deleted
auxiliary instance file /u01/aux/CDB1/controlfile/o1_mf_9s5f3180_.ctl deleted
auxiliary instance file tspitr_peCr_89262.dmp deleted
Finished recover at 07-JUN-14登入後複製
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MySQL与其他编程语言相比，主要用于存储和管理数据，而其他语言如Python、Java、C 则用于逻辑处理和应用开发。MySQL以其高性能、可扩展性和跨平台支持著称，适合数据管理需求，而其他语言在各自领域如数据分析、企业应用和系统编程中各有优势。
MySQL索引基數如何影響查詢性能？
Apr 14, 2025 am 12:18 AM
MySQL索引基数对查询性能有显著影响：1.高基数索引能更有效地缩小数据范围，提高查询效率；2.低基数索引可能导致全表扫描，降低查询性能；3.在联合索引中，应将高基数列放在前面以优化查询。
