Până la versiunea 12c atunci când era nevoie să se recupereze o tabelă dintr-un backup rman trebuia restaurată toată baza de date după care se exporta cu data pump tabela dorită iar în cele din urma tabela era importată în baza de date inițială. Întreg procesul fiind costisitor ca și timp iar efortul logistic nu este de neglijat, în general desfășurându-se pe un host separat. In ultima versiune a bazei de date mecanismul a fost destul de mult simplificat astfel încât nu este nevoie decât sa ne asigurăm că backup-ul este disponibil și putină răbdare după care Oracle va face totul în locul nostru…să vedem cum…
SQL> select count(*) from oe.INVENTORIES; COUNT(*) ---------- 1112 SQL> drop table oe.INVENTORIES purge; Table dropped.
Acum am creat un scenariu cu ajutorul căruia putem verifica dacă putem restaura tabela pierdută.
RMAN> list backup of database summary; List of Backups =============== Key TY LV S Device Type Completion Time #Pieces #Copies Compressed Tag ------- -- -- - ----------- --------------- ------- ------- ---------- --- 2 B F A DISK 17-SEP-16 1 1 NO TAG20160917T154202
[oracle@localhost oradata]$ mkdir test [oracle@localhost oradata]$ du -skh * 3.1G orcl 0 test [oracle@localhost oradata]$ df -h . Filesystem Size Used Avail Use% Mounted on /dev/mapper/ol-root 23G 17G 5.6G 76% /
M-am asigurat că am backup și suficient spațiu disponibil pentru a restaura backup-ul bazei de date în /opt/oracle/oradata/test
Să începem:
RMAN> recover table oe.INVENTORIES until time "to_date('2016-09-17 16:03:00','yyyy-mm-dd hh24:mi:ss')" auxiliary destination '/opt/oracle/oradata/test';
Starting recover at 2016-09-17:16:23:26
using target database control file instead of recovery catalog
current log archived
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=46 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='bjEa'
initialization parameters used for automatic instance:
db_name=ORCL
db_unique_name=bjEa_pitr_ORCL
compatible=12.1.0.2.0
db_block_size=8192
db_files=200
diagnostic_dest=/opt/oracle
_system_trig_enabled=FALSE
sga_target=800M
processes=200
db_create_file_dest=/opt/oracle/oradata/test
log_archive_dest_1='location=/opt/oracle/oradata/test'
#No auxiliary parameter file used
starting up automatic instance ORCL
Oracle instance started
Total System Global Area 838860800 bytes
Fixed Size 2929936 bytes
Variable Size 230689520 bytes
Database Buffers 599785472 bytes
Redo Buffers 5455872 bytes
Automatic instance created
contents of Memory Script:
{
# set requested point in time
set until time "to_date('2016-09-17 16:03:00','yyyy-mm-dd hh24: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 2016-09-17:16:23:35
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=21 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 /opt/oracle/fast_recovery_area/ORCL/backupset/2016_09_17/o1_mf_ncsnf_TAG20160917T154202_cxtgkbfq_.b kp
channel ORA_AUX_DISK_1: piece handle=/opt/oracle/fast_recovery_area/ORCL/backupset/2016_09_17/o1_mf_ncsnf_TAG20160917T154202_cxtgkbfq_.bkp tag=TAG201 60917T154202
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:01
output file name=/opt/oracle/oradata/test/ORCL/controlfile/o1_mf_cxtjyql9_.ctl
Finished restore at 2016-09-17:16:23:36
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('2016-09-17 16:03:00','yyyy-mm-dd hh24: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 /opt/oracle/oradata/test/ORCL/datafile/o1_mf_temp_%u_.tmp in control file
Starting restore at 2016-09-17:16:23:41
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 /opt/oracle/oradata/test/ORCL/datafile/o1_mf_system_%u_.dbf
channel ORA_AUX_DISK_1: restoring datafile 00004 to /opt/oracle/oradata/test/ORCL/datafile/o1_mf_undotbs1_%u_.dbf
channel ORA_AUX_DISK_1: restoring datafile 00003 to /opt/oracle/oradata/test/ORCL/datafile/o1_mf_sysaux_%u_.dbf
channel ORA_AUX_DISK_1: reading from backup piece /opt/oracle/fast_recovery_area/ORCL/backupset/2016_09_17/o1_mf_nnndf_TAG20160917T154202_cxtgjt9g_.b kp
channel ORA_AUX_DISK_1: piece handle=/opt/oracle/fast_recovery_area/ORCL/backupset/2016_09_17/o1_mf_nnndf_TAG20160917T154202_cxtgjt9g_.bkp tag=TAG201 60917T154202
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:15
Finished restore at 2016-09-17:16:23:56
datafile 1 switched to datafile copy
input datafile copy RECID=4 STAMP=922811036 file name=/opt/oracle/oradata/test/ORCL/datafile/o1_mf_system_cxtjyx46_.dbf
datafile 4 switched to datafile copy
input datafile copy RECID=5 STAMP=922811036 file name=/opt/oracle/oradata/test/ORCL/datafile/o1_mf_undotbs1_cxtjyx4q_.dbf
datafile 3 switched to datafile copy
input datafile copy RECID=6 STAMP=922811036 file name=/opt/oracle/oradata/test/ORCL/datafile/o1_mf_sysaux_cxtjyx4n_.dbf
contents of Memory Script:
{
# set requested point in time
set until time "to_date('2016-09-17 16:03:00','yyyy-mm-dd hh24: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 2016-09-17:16:23:56
using channel ORA_AUX_DISK_1
starting media recovery
archived log for thread 1 with sequence 15 is already on disk as file /opt/oracle/fast_recovery_area/ORCL/archivelog/2016_09_17/o1_mf_1_15_cxtgkckn_. arc
archived log for thread 1 with sequence 16 is already on disk as file /opt/oracle/fast_recovery_area/ORCL/archivelog/2016_09_17/o1_mf_1_16_cxtjyg7f_. arc
archived log file name=/opt/oracle/fast_recovery_area/ORCL/archivelog/2016_09_17/o1_mf_1_15_cxtgkckn_.arc thread=1 sequence=15
archived log file name=/opt/oracle/fast_recovery_area/ORCL/archivelog/2016_09_17/o1_mf_1_16_cxtjyg7f_.arc thread=1 sequence=16
media recovery complete, elapsed time: 00:00:01
Finished recover at 2016-09-17:16:23:57
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 =
''/opt/oracle/oradata/test/ORCL/controlfile/o1_mf_cxtjyql9_.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 838860800 bytes
Fixed Size 2929936 bytes
Variable Size 230689520 bytes
Database Buffers 599785472 bytes
Redo Buffers 5455872 bytes
sql statement: alter system set control_files = ''/opt/oracle/oradata/test/ORCL/controlfile/o1_mf_cxtjyql9_.ctl'' comment= ''RMAN set'' scope=spfile
Oracle instance shut down
connected to auxiliary database (not started)
Oracle instance started
Total System Global Area 838860800 bytes
Fixed Size 2929936 bytes
Variable Size 230689520 bytes
Database Buffers 599785472 bytes
Redo Buffers 5455872 bytes
sql statement: alter database mount clone database
contents of Memory Script:
{
# set requested point in time
set until time "to_date('2016-09-17 16:03:00','yyyy-mm-dd hh24: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 2016-09-17:16:24:39
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=21 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 /opt/oracle/oradata/test/BJEA_PITR_ORCL/datafile/o1_mf_example_%u_.dbf
channel ORA_AUX_DISK_1: reading from backup piece /opt/oracle/fast_recovery_area/ORCL/backupset/2016_09_17/o1_mf_nnndf_TAG20160917T154202_cxtgjt9g_.bkp
channel ORA_AUX_DISK_1: piece handle=/opt/oracle/fast_recovery_area/ORCL/backupset/2016_09_17/o1_mf_nnndf_TAG20160917T154202_cxtgjt9g_.bkp tag=TAG20160917T154202
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:15
Finished restore at 2016-09-17:16:24:54
datafile 5 switched to datafile copy
input datafile copy RECID=8 STAMP=922811094 file name=/opt/oracle/oradata/test/BJEA_PITR_ORCL/datafile/o1_mf_example_cxtk0qcg_.dbf
contents of Memory Script:
{
# set requested point in time
set until time "to_date('2016-09-17 16:03:00','yyyy-mm-dd hh24:mi:ss')";
# online the datafiles restored or switched
sql clone "alter database datafile 5 online";
# recover and open resetlogs
recover clone database tablespace "EXAMPLE", "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 2016-09-17:16:24:54
using channel ORA_AUX_DISK_1
starting media recovery
archived log for thread 1 with sequence 15 is already on disk as file /opt/oracle/fast_recovery_area/ORCL/archivelog/2016_09_17/o1_mf_1_15_cxtgkckn_.arc
archived log for thread 1 with sequence 16 is already on disk as file /opt/oracle/fast_recovery_area/ORCL/archivelog/2016_09_17/o1_mf_1_16_cxtjyg7f_.arc
archived log file name=/opt/oracle/fast_recovery_area/ORCL/archivelog/2016_09_17/o1_mf_1_15_cxtgkckn_.arc thread=1 sequence=15
archived log file name=/opt/oracle/fast_recovery_area/ORCL/archivelog/2016_09_17/o1_mf_1_16_cxtjyg7f_.arc thread=1 sequence=16
media recovery complete, elapsed time: 00:00:00
Finished recover at 2016-09-17:16:24:54
database opened
contents of Memory Script:
{
# create directory for datapump import
sql "create or replace directory TSPITR_DIROBJ_DPDIR as ''
/opt/oracle/oradata/test''";
# create directory for datapump export
sql clone "create or replace directory TSPITR_DIROBJ_DPDIR as ''
/opt/oracle/oradata/test''";
}
executing Memory Script
sql statement: create or replace directory TSPITR_DIROBJ_DPDIR as ''/opt/oracle/oradata/test''
sql statement: create or replace directory TSPITR_DIROBJ_DPDIR as ''/opt/oracle/oradata/test''
Performing export of tables...
EXPDP> Starting "SYS"."TSPITR_EXP_bjEa_Fwds":
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/GRANT/OWNER_GRANT/OBJECT_GRANT
EXPDP> Processing object type TABLE_EXPORT/TABLE/COMMENT
EXPDP> Processing object type TABLE_EXPORT/TABLE/INDEX/INDEX
EXPDP> Processing object type TABLE_EXPORT/TABLE/CONSTRAINT/CONSTRAINT
EXPDP> Processing object type TABLE_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS
EXPDP> Processing object type TABLE_EXPORT/TABLE/CONSTRAINT/REF_CONSTRAINT
EXPDP> Processing object type TABLE_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
EXPDP> Processing object type TABLE_EXPORT/TABLE/STATISTICS/MARKER
EXPDP> . . exported "OE"."INVENTORIES" 21.77 KB 1112 rows
EXPDP> Master table "SYS"."TSPITR_EXP_bjEa_Fwds" successfully loaded/unloaded
EXPDP> ******************************************************************************
EXPDP> Dump file set for SYS.TSPITR_EXP_bjEa_Fwds is:
EXPDP> /opt/oracle/oradata/test/tspitr_bjEa_77335.dmp
EXPDP> Job "SYS"."TSPITR_EXP_bjEa_Fwds" successfully completed at Sat Sep 17 16:25:34 2016 elapsed 0 00:00:18
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_bjEa_kEax" successfully loaded/unloaded
IMPDP> Starting "SYS"."TSPITR_IMP_bjEa_kEax":
IMPDP> Processing object type TABLE_EXPORT/TABLE/TABLE
IMPDP> Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
IMPDP> . . imported "OE"."INVENTORIES" 21.77 KB 1112 rows
IMPDP> Processing object type TABLE_EXPORT/TABLE/GRANT/OWNER_GRANT/OBJECT_GRANT
IMPDP> Processing object type TABLE_EXPORT/TABLE/COMMENT
IMPDP> Processing object type TABLE_EXPORT/TABLE/INDEX/INDEX
IMPDP> Processing object type TABLE_EXPORT/TABLE/CONSTRAINT/CONSTRAINT
IMPDP> Processing object type TABLE_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS
IMPDP> Processing object type TABLE_EXPORT/TABLE/CONSTRAINT/REF_CONSTRAINT
IMPDP> Processing object type TABLE_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
IMPDP> Processing object type TABLE_EXPORT/TABLE/STATISTICS/MARKER
IMPDP> Job "SYS"."TSPITR_IMP_bjEa_kEax" successfully completed at Sat Sep 17 16:25:53 2016 elapsed 0 00:00:14
Import completed
Removing automatic instance
Automatic instance removed
auxiliary instance file /opt/oracle/oradata/test/ORCL/datafile/o1_mf_temp_cxtjzfg8_.tmp deleted
auxiliary instance file /opt/oracle/oradata/test/BJEA_PITR_ORCL/onlinelog/o1_mf_3_cxtk175y_.log deleted
auxiliary instance file /opt/oracle/oradata/test/BJEA_PITR_ORCL/onlinelog/o1_mf_2_cxtk171b_.log deleted
auxiliary instance file /opt/oracle/oradata/test/BJEA_PITR_ORCL/onlinelog/o1_mf_1_cxtk16s8_.log deleted
auxiliary instance file /opt/oracle/oradata/test/BJEA_PITR_ORCL/datafile/o1_mf_example_cxtk0qcg_.dbf deleted
auxiliary instance file /opt/oracle/oradata/test/ORCL/datafile/o1_mf_sysaux_cxtjyx4n_.dbf deleted
auxiliary instance file /opt/oracle/oradata/test/ORCL/datafile/o1_mf_undotbs1_cxtjyx4q_.dbf deleted
auxiliary instance file /opt/oracle/oradata/test/ORCL/datafile/o1_mf_system_cxtjyx46_.dbf deleted
auxiliary instance file /opt/oracle/oradata/test/ORCL/controlfile/o1_mf_cxtjyql9_.ctl deleted
auxiliary instance file tspitr_bjEa_77335.dmp deleted
Finished recover at 2016-09-17:16:25:54
SQL> select count(*) from oe.INVENTORIES; COUNT(*) ---------- 1112
Din output-ul restaurarii se vede destul de clar că rman-ul urmează exact aceeași procedura despre care vorbeam la începutul articolului cu mențiunea ca totul se întâmplă cu ajutorul unei singure comenzi
„recover tables oe.INVENTORIES until time „to_date(‘2016-09-17 16:03:00′,’yyyy-mm-dd hh24:mi:ss’)”
auxiliary destination ‘/opt/oracle/oradata/test’;”.
In funcție de situația în care vă aflați există posibilitatea de a restaura tabela cu altă denumire, de exemplu:
„recover tables oe.INVENTORIES until time „to_date(‘2016-09-17 16:03:00′,’yyyy-mm-dd hh24:mi:ss’)”
auxiliary destination ‘/opt/oracle/oradata/test’
remap table ‘OE’.’INVENTORIES’:’INVENTORIES_RECOVER’;”
oradbaro 