Saturday, 17 October 2015

Table recovery in 12c

Tables point in time recovery 12c

It is now possible to recover a particular table to a point in time. 

When to use table point in time recovery?

Tablespace point in time is not recommend for the following scenario
                               Small number of tables to be recovered.
                              When tablespace is not self contained.

Flashback is not possible
a)       When the drop table is purged from recyclebin.
b)       Flashback table is not possible (Undo not available /  table structural change).

Steps
1)  Connect the target instance.
2)  Recover table command
3)  RMAN creates auxiliary instance in the auxiliary destination provided.
4)  RMAN recovers the table or table partition to the specified time.
5)  Exports the table to the auxiliary dump destination.
6)  Imports the table in to the target database if not NOTABLE IMPORT specified.
7)  Optionally remaps the table to different name.
Eg.

SQL> select count(*) from manzoor.emp;

  COUNT(*)
----------
      1000

SQL> select current_scn from V$database;

CURRENT_SCN
-----------
    6971250

SQL> delete from manzoor.emp where rownum <500;

499 rows deleted.

SQL> commit;

Commit complete.


[oracle@rhel11gr2rac1 ~]$ mkdir -p /backup/aux_dest
[oracle@rhel11gr2rac1 ~]$ mkdir -p /backup/aux_dest/dump_dest

The below will create a auxiliary destination and startup an auxiliary destination, restores the system/sysaux/undo & the tablespace in which the said objects resides, recovers it until scn, takes export dump in the below said directory, import into the table with remap tables clause in the main database.


RMAN> RMAN> run
 {
 recover table manzoor.emp
 until scn 6971250
 auxiliary destination '/backup/aux_dest'
 datapump  destination '/backup/aux_dest/dump_dest'
 dump file 'manzoor_emp_table.dmp'
 remap table manzoor.emp:emp_reco;
 }
2> 3> 4> 5> 6> 7> 8> 9>

Starting recover at 08-SEP-15
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=57 device type=DISK
allocated channel: ORA_DISK_2
channel ORA_DISK_2: SID=66 device type=DISK
allocated channel: ORA_DISK_3
channel ORA_DISK_3: SID=67 device type=DISK
allocated channel: ORA_DISK_4
channel ORA_DISK_4: SID=61 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='ciah'

initialization parameters used for automatic instance:
db_name=PURCHASE
db_unique_name=ciah_pitr_PURCHASE
compatible=12.1.0.0.0
db_block_size=8192
db_files=200
diagnostic_dest=/oracle/product
_system_trig_enabled=FALSE
sga_target=1024M
processes=200
db_create_file_dest=/backup/aux_dest
log_archive_dest_1='location=/backup/aux_dest'
#No auxiliary parameter file used


starting up automatic instance PURCHASE

Oracle instance started

Total System Global Area    1073741824 bytes

Fixed Size                     2932632 bytes
Variable Size                281018472 bytes
Database Buffers             784334848 bytes
Redo Buffers                   5455872 bytes
Automatic instance created

contents of Memory Script:
{
# set requested point in time
set until  scn 6971250;
# 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 08-SEP-15
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=24 device type=DISK
allocated channel: ORA_AUX_DISK_2
channel ORA_AUX_DISK_2: SID=25 device type=DISK
allocated channel: ORA_AUX_DISK_3
channel ORA_AUX_DISK_3: SID=26 device type=DISK
allocated channel: ORA_AUX_DISK_4
channel ORA_AUX_DISK_4: SID=27 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 /oracle/purchase_bkp/purchase_bkp_4nqgkhhm_1_1.bkp
channel ORA_AUX_DISK_1: piece handle=/oracle/purchase_bkp/purchase_bkp_4nqgkhhm_1_1.bkp tag=TAG20150908T085620
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:03
output file name=/backup/aux_dest/PURCHASE/controlfile/o1_mf_bywj44lq_.ctl
Finished restore at 08-SEP-15

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 6971250;
# 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 /backup/aux_dest/PURCHASE/datafile/o1_mf_temp_%u_.tmp in control file

Starting restore at 08-SEP-15
using channel ORA_AUX_DISK_1
using channel ORA_AUX_DISK_2
using channel ORA_AUX_DISK_3
using channel ORA_AUX_DISK_4

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 /backup/aux_dest/PURCHASE/datafile/o1_mf_sysaux_%u_.dbf
channel ORA_AUX_DISK_1: reading from backup piece /oracle/purchase_bkp/purchase_bkp_4mqgkhhm_1_1.bkp
channel ORA_AUX_DISK_2: starting datafile backup set restore
channel ORA_AUX_DISK_2: specifying datafile(s) to restore from backup set
channel ORA_AUX_DISK_2: restoring datafile 00001 to /backup/aux_dest/PURCHASE/datafile/o1_mf_system_%u_.dbf
channel ORA_AUX_DISK_2: reading from backup piece /oracle/purchase_bkp/purchase_bkp_4lqgkhhm_1_1.bkp
channel ORA_AUX_DISK_3: starting datafile backup set restore
channel ORA_AUX_DISK_3: specifying datafile(s) to restore from backup set
channel ORA_AUX_DISK_3: restoring datafile 00004 to /backup/aux_dest/PURCHASE/datafile/o1_mf_undotbs1_%u_.dbf
channel ORA_AUX_DISK_3: reading from backup piece /oracle/purchase_bkp/purchase_bkp_4kqgkhhl_1_1.bkp
channel ORA_AUX_DISK_3: piece handle=/oracle/purchase_bkp/purchase_bkp_4kqgkhhl_1_1.bkp tag=TAG20150908T085620
channel ORA_AUX_DISK_3: restored backup piece 1
channel ORA_AUX_DISK_3: restore complete, elapsed time: 00:01:17
channel ORA_AUX_DISK_1: piece handle=/oracle/purchase_bkp/purchase_bkp_4mqgkhhm_1_1.bkp tag=TAG20150908T085620
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:04:39
channel ORA_AUX_DISK_2: piece handle=/oracle/purchase_bkp/purchase_bkp_4lqgkhhm_1_1.bkp tag=TAG20150908T085620
channel ORA_AUX_DISK_2: restored backup piece 1
channel ORA_AUX_DISK_2: restore complete, elapsed time: 00:04:58
Finished restore at 08-SEP-15

datafile 1 switched to datafile copy
input datafile copy RECID=4 STAMP=889869754 file name=/backup/aux_dest/PURCHASE/datafile/o1_mf_system_bywj4h8s_.dbf
datafile 4 switched to datafile copy
input datafile copy RECID=5 STAMP=889869754 file name=/backup/aux_dest/PURCHASE/datafile/o1_mf_undotbs1_bywj4j2g_.dbf
datafile 3 switched to datafile copy
input datafile copy RECID=6 STAMP=889869754 file name=/backup/aux_dest/PURCHASE/datafile/o1_mf_sysaux_bywj4hs2_.dbf

contents of Memory Script:
{
# set requested point in time
set until  scn 6971250;
# 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 08-SEP-15
using channel ORA_AUX_DISK_1
using channel ORA_AUX_DISK_2
using channel ORA_AUX_DISK_3
using channel ORA_AUX_DISK_4

starting media recovery

archived log for thread 1 with sequence 242 is already on disk as file /oracle/product/fast_recovery_area/PURCHASE/archivelog/2015_09_08/o1_mf_1_242_bywgrc1k_.arc
channel ORA_AUX_DISK_1: starting archived log restore to default destination
channel ORA_AUX_DISK_1: restoring archived log
archived log thread=1 sequence=240
channel ORA_AUX_DISK_1: reading from backup piece /oracle/purchase_bkp/purchase_bkp_4qqgki95_1_1.bkp
channel ORA_AUX_DISK_2: starting archived log restore to default destination
channel ORA_AUX_DISK_2: restoring archived log
archived log thread=1 sequence=241
channel ORA_AUX_DISK_2: reading from backup piece /oracle/purchase_bkp/purchase_bkp_4sqgki96_1_1.bkp
channel ORA_AUX_DISK_2: piece handle=/oracle/purchase_bkp/purchase_bkp_4sqgki96_1_1.bkp tag=TAG20150908T090852
channel ORA_AUX_DISK_2: restored backup piece 1
channel ORA_AUX_DISK_2: restore complete, elapsed time: 00:00:01
channel ORA_AUX_DISK_1: piece handle=/oracle/purchase_bkp/purchase_bkp_4qqgki95_1_1.bkp tag=TAG20150908T090852
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:03
archived log file name=/backup/aux_dest/1_240_888427429.dbf thread=1 sequence=240
archived log file name=/backup/aux_dest/1_241_888427429.dbf thread=1 sequence=241
archived log file name=/oracle/product/fast_recovery_area/PURCHASE/archivelog/2015_09_08/o1_mf_1_242_bywgrc1k_.arc thread=1 sequence=242
media recovery complete, elapsed time: 00:00:05
Finished recover at 08-SEP-15

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 =
  ''/backup/aux_dest/PURCHASE/controlfile/o1_mf_bywj44lq_.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    1073741824 bytes

Fixed Size                     2932632 bytes
Variable Size                285212776 bytes
Database Buffers             780140544 bytes
Redo Buffers                   5455872 bytes

sql statement: alter system set  control_files =   ''/backup/aux_dest/PURCHASE/controlfile/o1_mf_bywj44lq_.ctl'' comment= ''RMAN set'' scope=spfile

Oracle instance shut down

connected to auxiliary database (not started)
Oracle instance started

Total System Global Area    1073741824 bytes

Fixed Size                     2932632 bytes
Variable Size                285212776 bytes
Database Buffers             780140544 bytes
Redo Buffers                   5455872 bytes

sql statement: alter database mount clone database

contents of Memory Script:
{
# set requested point in time
set until  scn 6971250;
# set destinations for recovery set and auxiliary set datafiles
set newname for datafile  2 to new;
# restore the tablespaces in the recovery set and the auxiliary set
restore clone datafile  2;

switch clone datafile all;
}
executing Memory Script

executing command: SET until clause

executing command: SET NEWNAME

Starting restore at 08-SEP-15
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=21 device type=DISK
allocated channel: ORA_AUX_DISK_2
channel ORA_AUX_DISK_2: SID=24 device type=DISK
allocated channel: ORA_AUX_DISK_3
channel ORA_AUX_DISK_3: SID=25 device type=DISK
allocated channel: ORA_AUX_DISK_4
channel ORA_AUX_DISK_4: SID=26 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 00002 to /backup/aux_dest/CIAH_PITR_PURCHASE/datafile/o1_mf_active_d_%u_.dbf
channel ORA_AUX_DISK_1: reading from backup piece /oracle/purchase_bkp/purchase_bkp_4lqgkhhm_1_1.bkp
channel ORA_AUX_DISK_1: piece handle=/oracle/purchase_bkp/purchase_bkp_4lqgkhhm_1_1.bkp tag=TAG20150908T085620
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:16
Finished restore at 08-SEP-15

datafile 2 switched to datafile copy
input datafile copy RECID=8 STAMP=889869857 file name=/backup/aux_dest/CIAH_PITR_PURCHASE/datafile/o1_mf_active_d_bywjjkt5_.dbf

contents of Memory Script:
{
# set requested point in time
set until  scn 6971250;
# online the datafiles restored or switched
sql clone "alter database datafile  2 online";
# recover and open resetlogs
recover clone database tablespace  "ACTIVE_DATA", "SYSTEM", "UNDOTBS1", "SYSAUX" delete archivelog;
alter clone database open resetlogs;
}
executing Memory Script

executing command: SET until clause

sql statement: alter database datafile  2 online

Starting recover at 08-SEP-15
using channel ORA_AUX_DISK_1
using channel ORA_AUX_DISK_2
using channel ORA_AUX_DISK_3
using channel ORA_AUX_DISK_4

starting media recovery

archived log for thread 1 with sequence 242 is already on disk as file /oracle/product/fast_recovery_area/PURCHASE/archivelog/2015_09_08/o1_mf_1_242_bywgrc1k_.arc
channel ORA_AUX_DISK_1: starting archived log restore to default destination
channel ORA_AUX_DISK_1: restoring archived log
archived log thread=1 sequence=240
channel ORA_AUX_DISK_1: reading from backup piece /oracle/purchase_bkp/purchase_bkp_4qqgki95_1_1.bkp
channel ORA_AUX_DISK_2: starting archived log restore to default destination
channel ORA_AUX_DISK_2: restoring archived log
archived log thread=1 sequence=241
channel ORA_AUX_DISK_2: reading from backup piece /oracle/purchase_bkp/purchase_bkp_4sqgki96_1_1.bkp
channel ORA_AUX_DISK_1: piece handle=/oracle/purchase_bkp/purchase_bkp_4qqgki95_1_1.bkp tag=TAG20150908T090852
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:01
archived log file name=/backup/aux_dest/1_240_888427429.dbf thread=1 sequence=240
channel clone_default: deleting archived log(s)
archived log file name=/backup/aux_dest/1_240_888427429.dbf RECID=194 STAMP=889869861
channel ORA_AUX_DISK_2: piece handle=/oracle/purchase_bkp/purchase_bkp_4sqgki96_1_1.bkp tag=TAG20150908T090852
channel ORA_AUX_DISK_2: restored backup piece 1
channel ORA_AUX_DISK_2: restore complete, elapsed time: 00:00:02
archived log file name=/backup/aux_dest/1_241_888427429.dbf thread=1 sequence=241
channel clone_default: deleting archived log(s)
archived log file name=/backup/aux_dest/1_241_888427429.dbf RECID=193 STAMP=889869860
archived log file name=/oracle/product/fast_recovery_area/PURCHASE/archivelog/2015_09_08/o1_mf_1_242_bywgrc1k_.arc thread=1 sequence=242
media recovery complete, elapsed time: 00:00:00
Finished recover at 08-SEP-15

database opened

contents of Memory Script:
{
# create directory for datapump import
sql "create or replace directory TSPITR_DIROBJ_DPDIR as ''
/backup/aux_dest/dump_dest''";
# create directory for datapump export
sql clone "create or replace directory TSPITR_DIROBJ_DPDIR as ''
/backup/aux_dest/dump_dest''";
}
executing Memory Script

sql statement: create or replace directory TSPITR_DIROBJ_DPDIR as ''/backup/aux_dest/dump_dest''

sql statement: create or replace directory TSPITR_DIROBJ_DPDIR as ''/backup/aux_dest/dump_dest''

Performing export of tables...
   EXPDP> Starting "SYS"."TSPITR_EXP_ciah_Bmrm":
   EXPDP> Estimate in progress using BLOCKS method...
   EXPDP> Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
   EXPDP> Total estimation using BLOCKS method: 128 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/STATISTICS/TABLE_STATISTICS
   EXPDP> Processing object type TABLE_EXPORT/TABLE/STATISTICS/MARKER
   EXPDP> . . exported "MANZOOR"."EMP"                             71.03 KB    1000 rows
   EXPDP> Master table "SYS"."TSPITR_EXP_ciah_Bmrm" successfully loaded/unloaded
   EXPDP> ******************************************************************************
   EXPDP> Dump file set for SYS.TSPITR_EXP_ciah_Bmrm is:
   EXPDP>   /backup/aux_dest/dump_dest/manzoor_emp_table.dmp
   EXPDP> Job "SYS"."TSPITR_EXP_ciah_Bmrm" successfully completed at Tue Sep 8 10:07:52 2015 elapsed 0 00:02:08
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_ciah_ygCq" successfully loaded/unloaded
   IMPDP> Starting "SYS"."TSPITR_IMP_ciah_ygCq":
   IMPDP> Processing object type TABLE_EXPORT/TABLE/TABLE
   IMPDP> Processing object type TABLE_EXPORT/TABLE/TABLE_DATA
   IMPDP> . . imported "MANZOOR"."EMP_RECO"                        71.03 KB    1000 rows
   IMPDP> Processing object type TABLE_EXPORT/TABLE/GRANT/OWNER_GRANT/OBJECT_GRANT
   IMPDP> Processing object type TABLE_EXPORT/TABLE/STATISTICS/TABLE_STATISTICS
   IMPDP> Processing object type TABLE_EXPORT/TABLE/STATISTICS/MARKER
   IMPDP> Job "SYS"."TSPITR_IMP_ciah_ygCq" successfully completed at Tue Sep 8 10:09:52 2015 elapsed 0 00:01:33
Import completed


Removing automatic instance
Automatic instance removed
auxiliary instance file /backup/aux_dest/PURCHASE/datafile/o1_mf_temp_bywjg9b7_.tmp deleted
auxiliary instance file /backup/aux_dest/CIAH_PITR_PURCHASE/onlinelog/o1_mf_3_bywjk935_.log deleted
auxiliary instance file /backup/aux_dest/CIAH_PITR_PURCHASE/onlinelog/o1_mf_2_bywjk7x9_.log deleted
auxiliary instance file /backup/aux_dest/CIAH_PITR_PURCHASE/onlinelog/o1_mf_1_bywjk6m1_.log deleted
auxiliary instance file /backup/aux_dest/CIAH_PITR_PURCHASE/datafile/o1_mf_active_d_bywjjkt5_.dbf deleted
auxiliary instance file /backup/aux_dest/PURCHASE/datafile/o1_mf_sysaux_bywj4hs2_.dbf deleted
auxiliary instance file /backup/aux_dest/PURCHASE/datafile/o1_mf_undotbs1_bywj4j2g_.dbf deleted
auxiliary instance file /backup/aux_dest/PURCHASE/datafile/o1_mf_system_bywj4h8s_.dbf deleted
auxiliary instance file /backup/aux_dest/PURCHASE/controlfile/o1_mf_bywj44lq_.ctl deleted
auxiliary instance file manzoor_emp_table.dmp deleted
Finished recover at 08-SEP-15

RMAN> select count(*) from manzoor.emp_reco;

  COUNT(*)
----------
      1000

RMAN> drop table manzoor.emp;

Statement processed

RMAN> alter table manzoor.emp_reco rename to emp;

Statement processed

RMAN> select count(*) from manzoor.emp;

  COUNT(*)
----------

      1000

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