下面做一個實驗，使用scn進行不完全恢復（做之前要確保資料庫有有效備份）：
首先在hh使用者下建立一張表h2，在表中插入資料：
SQL> create table h2(id int);

Table created.

SQL> insert into h2 values(1);

1 row created.

SQL> commit;

Commit complete.

SQL> insert into h2 values(2);

1 row created.

SQL> select * from h2;

ID
----------
1
2

然後記錄下此時的scn：
SQL> conn /as sysdba
Connected.

SQL> select dbms_flashback.get_system_change_number scn from dual;

SCN
----------
850798

接著刪除表h2:
SQL> conn hh/hh
Connected.
SQL> drop table h2;

Table dropped.

現在使用rman將資料庫恢復到h2被刪除之前：
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.

[oracle@localhost ~]$ rman target / nocatalog

Recovery Manager: Release 11.2.0.1.0 - Production on Fri Aug 22 23:49:41 2014

Copyright (c) 1982, 2009, Oracle and/or its affiliates. All rights reserved.

connected to target database (not started)

RMAN> startup mount;

Oracle instance started
database mounted

Total System Global Area 849530880 bytes

Fixed Size 1339824 bytes
Variable Size 553651792 bytes
Database Buffers 289406976 bytes
Redo Buffers 5132288 bytes

RMAN> restore database until scn 850798
2> ;

Starting restore at 22-AUG-14
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=18 device type=DISK

skipping datafile 6; already restored to file /u01/app/datafile/test01.dbf
channel ORA_DISK_1: starting datafile backup set restore
channel ORA_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_DISK_1: restoring datafile 00003 to /u01/app/oracle/oradata/orcl/undotbs01.dbf
channel ORA_DISK_1: restoring datafile 00005 to /u01/app/oracle/oradata/orcl/example01.dbf
channel ORA_DISK_1: reading from backup piece /u01/app/backup/fulldb_0lpgkfcr_1_1
channel ORA_DISK_1: piece handle=/u01/app/backup/fulldb_0lpgkfcr_1_1 tag=FULLDB
channel ORA_DISK_1: restored backup piece 1
channel ORA_DISK_1: restore complete, elapsed time: 00:00:07
channel ORA_DISK_1: starting datafile backup set restore
channel ORA_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_DISK_1: restoring datafile 00002 to /u01/app/oracle/oradata/orcl/sysaux01.dbf
channel ORA_DISK_1: restoring datafile 00004 to /u01/app/oracle/oradata/orcl/users01.dbf
channel ORA_DISK_1: restoring datafile 00007 to /u01/app/oracle/oradata/orcl/hh01.dbf
channel ORA_DISK_1: reading from backup piece /u01/app/backup/fulldb_0kpgkfcr_1_1
channel ORA_DISK_1: piece handle=/u01/app/backup/fulldb_0kpgkfcr_1_1 tag=FULLDB
channel ORA_DISK_1: restored backup piece 1
channel ORA_DISK_1: restore complete, elapsed time: 00:00:35
channel ORA_DISK_1: starting datafile backup set restore
channel ORA_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_DISK_1: restoring datafile 00001 to /u01/app/oracle/oradata/orcl/system01.dbf
channel ORA_DISK_1: reading from backup piece /u01/app/backup/fulldb_0jpgkfcr_1_1
channel ORA_DISK_1: piece handle=/u01/app/backup/fulldb_0jpgkfcr_1_1 tag=FULLDB
channel ORA_DISK_1: restored backup piece 1
channel ORA_DISK_1: restore complete, elapsed time: 00:00:45
Finished restore at 22-AUG-14

RMAN> recover database until scn 850798
2> ;

Starting recover at 22-AUG-14
using channel ORA_DISK_1

starting media recovery

archived log for thread 1 with sequence 11 is already on disk as file /u01/app/archivelog/dest1/1_11_856205535.dbf
archived log for thread 1 with sequence 1 is already on disk as file /u01/app/archivelog/dest1/1_1_856304357.dbf
archived log for thread 1 with sequence 2 is already on disk as file /u01/app/archivelog/dest1/1_2_856304357.dbf
archived log file name=/u01/app/archivelog/dest1/1_11_856205535.dbf thread=1 sequence=11
media recovery complete, elapsed time: 00:00:03
Finished recover at 22-AUG-14

使用resetlogs開啟資料庫：
SQL> alter database open resetlogs;

Database altered.

SQL> select * from hh.h2;

ID
----------
1
2

表h2已經回來了。

oracle基於scn的不完全恢復

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