Oracle 基于 RMAN 的不完全恢复(incomplete recovery by RMAN)

wangpanyang 2013-07-05

Oracle 数据库可以实现数据库不完全恢复与完全恢复。完全恢复是将数据库恢复到最新时刻,也就是无损恢复,保证数据库无丢失的恢复。而不完全恢复则是根据需要特意将数据库恢复到某个过去的特定时间点或特定的SCN以及特定的Sequence。我们可以通过基于用户管理的不完全恢复实现,也可以通过基于RMAN方式来实现。本文主要描述是基于RMAN的不完全恢复的几种情形并给出示例。有关数据库备份恢复,RMAN备份恢复的概念与实战可以参考文章尾部给出的链接。 

一、不完全恢复的步骤
    a、关闭数据库并备份数据库(以防止恢复失败)
    b、启动数据库到mount 状态
    c、还原数据库
    d、将数据库恢复至某个时间点、序列、或系统改变号
    e、使用RESETLOGS关键字打开数据库 

二、不完全恢复的几种类型
  Type of Recovery        Function
  -------------------    ----------------------------
  Time-based recovery    Recovers the data up to a specified point in time.
  Cancel-based recovery  Recovers until you issue the CANCEL statement (not available when using Recovery Manager).
  Change-based recovery  Recovers until the specified SCN.
  Log sequence recovery  Recovers until the specified log sequence number (only available when using Recovery Manager).
 
三、RMAN不完全恢复的主要操作命令

a、基于TIME 参数不完全恢复
run {
      shutdown immediate;
      startup mount;
      set until time "to_date('20130705 10:09:53','yyyymmdd hh24:mi:ss')";
      restore database;
      recover database;
      alter database open resetlogs;
}

b、基于SCN 参数不完全恢复
run {
      shutdown immediate;
      startup mount;
      set until scn 3400;
      restore database;
      recover database;
      alter database open resetlogs;
}

c、基于SEQUENCE 参数不完全恢复:
run {
      shutdown immediate;
      startup mount;
      set until sequence 12903;
      restore database;
      recover database;
      alter database open resetlogs;
}

四、演示RMAN不完全恢复

1、准备环境
--->首先备份数据库
[oracle@node1 ~]$ export ORACLE_SID=oradb
[oracle@node1 ~]$ more rman_full.rcv
run{
allocate channel ch1 device type disk;
allocate channel ch2 device type disk;
crosscheck archivelog all;
delete noprompt expired archivelog all;
backup database format '/u02/rman/full_%d_%U' tag=full_bak
plus archivelog format '/u02/rman/arch_%d_%U' tag=arch;
release channel ch1;
release channel ch2;
}
[oracle@node1 ~]$ rman target / cmdfile=/home/oracle/rman_full.rcv log=/home/oracle/rman_full.log
RMAN> 2> 3> 4> 5> 6> 7> 8> 9> 10> 11>
--下面是产生的备份文件
[oracle@node1 ~]$ ls -hltr /u02/rman
total 1.1G
-rw-r----- 1 oracle asmadmin  31M Jul  5 09:44 arch_ORADB_03odvgv2_1_1
-rw-r----- 1 oracle asmadmin 595M Jul  5 09:45 full_ORADB_04odvgv7_1_1
-rw-r----- 1 oracle asmadmin 490M Jul  5 09:45 full_ORADB_05odvgv7_1_1
-rw-r----- 1 oracle asmadmin  12K Jul  5 09:46 arch_ORADB_06odvh30_1_1 

--演示环境
SQL> select * from v$version where rownum<2;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production

SQL> conn scott/tiger;
Connected.

-->下面的查询得到当前已产生的归档日志
SQL> SELECT name,sequence# seq#,status,completion_time FROM v$archived_log;

NAME                                                      SEQ# S COMPLETION_TIME
---------------------------------------------------------- ---- - -----------------
/u02/DB/oradb/arch/2013_07_05/o1_mf_1_26_8xd97058_.arc      26 A 20130705 09:44:01
/u02/DB/oradb/arch/2013_07_05/o1_mf_1_27_8xd9c0f0_.arc      27 A 20130705 09:46:08
/u02/DB/oradb/arch/2013_07_05/o1_mf_1_28_8xdbcrht_.arc      28 A 20130705 10:03:36

-->创建测试用表并插入记录
10:07:01 SQL> create table t2(id varchar2(10), dt varchar2(20));

10:07:57 SQL> insert into t2 select 'Robinson',to_char(sysdate,'yyyymmdd hh24:mi:ss') from dual;

10:08:15 SQL> commit;

10:08:18 SQL> alter system archive log current;  -->对当前日志进行归档

-->下面的查询可知产生新的归档日志29
10:08:28 SQL> SELECT name,sequence# seq#,status,completion_time FROM v$archived_log where sequence#>=28;

NAME                                                        SEQ# S COMPLETION_TIME
------------------------------------------------------------ ---- - -----------------
/u02/DB/oradb/arch/2013_07_05/o1_mf_1_28_8xdbcrht_.arc        28 A 20130705 10:03:36
/u02/DB/oradb/arch/2013_07_05/o1_mf_1_29_8xdbnqx9_.arc        29 A 20130705 10:08:23

-->应证归档日志中包含记录Robinson
10:09:53 SQL> ho strings /u02/DB/oradb/arch/2013_07_05/o1_mf_1_29_8xdbnqx9_.arc | grep "Robinson"
Robinson

--->第二次插入记录
10:10:48 SQL> insert into t2 select 'Jackson',to_char(sysdate,'yyyymmdd hh24:mi:ss') from dual;

10:11:27 SQL> commit;

10:11:30 SQL> alter system archive log current;

10:11:47 SQL> SELECT name,sequence# seq#,status,completion_time FROM v$archived_log where sequence#>=28;

NAME                                                      SEQ# S COMPLETION_TIME
---------------------------------------------------------- ---- - -----------------
/u02/DB/oradb/arch/2013_07_05/o1_mf_1_28_8xdbcrht_.arc      28 A 20130705 10:03:36
/u02/DB/oradb/arch/2013_07_05/o1_mf_1_29_8xdbnqx9_.arc      29 A 20130705 10:08:23
/u02/DB/oradb/arch/2013_07_05/o1_mf_1_30_8xdbv338_.arc      30 A 20130705 10:11:47

10:12:17 SQL> ho strings /u02/DB/oradb/arch/2013_07_05/o1_mf_1_30_8xdbv338_.arc | grep "Jackson"
Jackson

-->查看当前数据库的SCN
10:12:34 SQL> select name,current_scn from v$database;

NAME                          CURRENT_SCN
------------------------------ -----------
ORADB                              1365679

--->第三次插入记录
10:15:07 SQL> insert into t2 select 'Winson',to_char(sysdate,'yyyymmdd hh24:mi:ss') from dual;

10:15:47 SQL> commit;

10:21:18 SQL> alter system switch logfile;     

--->第四次插入记录
10:22:53 SQL> insert into t2 select 'LastRecord',to_char(sysdate,'yyyymmdd hh24:mi:ss') from dual;

10:23:44 SQL> commit;

10:23:47 SQL> select * from t2;

ID        DT
---------- --------------------
Robinson  20130705 10:08:15
Jackson    20130705 10:11:27
Winson    20130705 10:15:47
LastRecord 20130705 10:23:44

10:23:52 SQL> alter system switch logfile;

-->下面是最终的归档日志情况
10:24:00 SQL> SELECT name,sequence# seq#,status,completion_time FROM v$archived_log where sequence#>=28;

NAME                                                        SEQ# S COMPLETION_TIME
------------------------------------------------------------ ---- - -----------------
/u02/DB/oradb/arch/2013_07_05/o1_mf_1_28_8xdbcrht_.arc        28 A 20130705 10:03:36
/u02/DB/oradb/arch/2013_07_05/o1_mf_1_29_8xdbnqx9_.arc        29 A 20130705 10:08:23
/u02/DB/oradb/arch/2013_07_05/o1_mf_1_30_8xdbv338_.arc        30 A 20130705 10:11:47
/u02/DB/oradb/arch/2013_07_05/o1_mf_1_31_8xdcg1wc_.arc        31 A 20130705 10:21:53
/u02/DB/oradb/arch/2013_07_05/o1_mf_1_32_8xdcl0rx_.arc        32 A 20130705 10:24:00

10:24:12 SQL> ho strings /u02/DB/oradb/arch/2013_07_05/o1_mf_1_31_8xdcg1wc_.arc | grep "Winson"
Winson

--->最后一次插入记录
10:25:16 SQL> insert into t2 select 'Completed',to_char(sysdate,'yyyymmdd hh24:mi:ss') from dual;

10:26:20 SQL> commit;

-->此时数据库当前的redo log并没有归档,因此插入的数据位于联机日志
10:27:40 SQL> ho strings /u02/DB/oradb/redo/redo03.log | grep "Completed"
        Completed

--->下面列出完成的记录与日志对照关系
SQL> select * from t2;

ID        DT                    对应的归档日志            对应的sequence
---------- --------------------  ------------------------  --------------
Robinson  20130705 10:08:15    o1_mf_1_29_8xdbnqx9_.arc              29
Jackson    20130705 10:11:27    o1_mf_1_30_8xdbv338_.arc              30
Winson    20130705 10:15:47    o1_mf_1_31_8xdcg1wc_.arc              31
LastRecord 20130705 10:23:44    o1_mf_1_32_8xdcl0rx_.arc              32
Completed  20130705 10:26:20    redo03.log

2、实施不完全恢复
a、基于时间点的不完全恢复
[oracle@node1 ~]$ rman target /

Recovery Manager: Release 11.2.0.1.0 - Production on Fri Jul 5 10:28:53 2013

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

connected to target database: ORADB (DBID=2557712192)

RMAN> run{
2> shutdown immediate;
3> startup mount;
4> set until time "to_date('20130705 10:09:53','yyyymmdd hh24:mi:ss')";
5> restore database;
6> recover database;
7> }

using target database control file instead of recovery catalog
database closed
database dismounted
Oracle instance shut down

connected to target database (not started)
Oracle instance started
database mounted

Total System Global Area    263639040 bytes

executing command: SET until clause

Starting restore at 20130705 10:33:36
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=24 device type=DISK

channel ORA_DISK_1: starting datafile backup set restore      ---->启动数据文件还原
channel ORA_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_DISK_1: restoring datafile 00001 to /u02/DB/oradb/oradata/system01.dbf
channel ORA_DISK_1: restoring datafile 00003 to /u02/DB/oradb/oradata/undotbs01.dbf
channel ORA_DISK_1: reading from backup piece /u02/rman/full_ORADB_04odvgv7_1_1
channel ORA_DISK_1: piece handle=/u02/rman/full_ORADB_04odvgv7_1_1 tag=FULL_BAK
channel ORA_DISK_1: restored backup piece 1
channel ORA_DISK_1: restore complete, elapsed time: 00:01:05
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 /u02/DB/oradb/oradata/sysaux01.dbf
channel ORA_DISK_1: restoring datafile 00004 to /u02/DB/oradb/oradata/users01.dbf
channel ORA_DISK_1: restoring datafile 00005 to /u02/DB/oradb/oradata/example01.dbf
channel ORA_DISK_1: reading from backup piece /u02/rman/full_ORADB_05odvgv7_1_1
channel ORA_DISK_1: piece handle=/u02/rman/full_ORADB_05odvgv7_1_1 tag=FULL_BAK
channel ORA_DISK_1: restored backup piece 1
channel ORA_DISK_1: restore complete, elapsed time: 00:00:45    --->完成数据文件还原
Finished restore at 20130705 10:35:28

Starting recover at 20130705 10:35:29  --->启动数据恢复
using channel ORA_DISK_1

starting media recovery
---->下面提示归档日志已经存在,是由于我们备份归档日志后并没有对其清除           
archived log for thread 1 with sequence 27 is already on disk as file /u02/DB/oradb/arch/2013_07_05/o1_mf_1_27_8xd9c0f0_.arc
archived log for thread 1 with sequence 28 is already on disk as file /u02/DB/oradb/arch/2013_07_05/o1_mf_1_28_8xdbcrht_.arc
archived log for thread 1 with sequence 29 is already on disk as file /u02/DB/oradb/arch/2013_07_05/o1_mf_1_29_8xdbnqx9_.arc
archived log for thread 1 with sequence 30 is already on disk as file /u02/DB/oradb/arch/2013_07_05/o1_mf_1_30_8xdbv338_.arc
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_27_8xd9c0f0_.arc thread=1 sequence=27 --->列出日志对应的sequence
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_28_8xdbcrht_.arc thread=1 sequence=28
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_29_8xdbnqx9_.arc thread=1 sequence=29
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_30_8xdbv338_.arc thread=1 sequence=30
media recovery complete, elapsed time: 00:00:09  --->介质恢复完成,可以看到介质恢复,日志apply到了30(不包含sequence 30的内容)
Finished recover at 20130705 10:35:42            --->完成恢复

RMAN> alter database open resetlogs;              --->手动open resetlogs

database opened

RMAN> host;     

[oracle@node1 ~]$ more query_t2.sh
#!/bin/bash
if [ -f ~/.bashrc ]; then 
        . ~/.bashrc 
fi 

export ORACLE_SID=oradb
sqlplus -S /nolog <<EOF
connect scott/tiger
select * from scott.t2;
exit;
EOF
exit

-->验证结果,记录Robinson已经被恢复
[oracle@node1 ~]$ ./query_t2.sh

ID        DT
---------- --------------------
Robinson  20130705 10:08:15

[oracle@node1 ~]$ exit
exit
host command complete

-->新的incarnation已经被产生,为3
RMAN> list incarnation;

List of Database Incarnations
DB Key  Inc Key DB Name  DB ID            STATUS  Reset SCN  Reset Time
------- ------- -------- ---------------- --- ---------- ----------
1      1      ORADB    2557712192      PARENT  1          20090813 23:00:48
2      2      ORADB    2557712192      PARENT  754488    20130111 17:37:07
3      3      ORADB    2557712192      CURRENT 1365530    20130705 10:37:15

b、基于SCN的不完全恢复
RMAN> shutdown immediate;
RMAN> startup mount;
RMAN> reset database to incarnation 2;  --->在此需要reset incarnation
database reset to incarnation 2

RMAN> run{
2> set until scn 1365679;
3> restore database;
4> recover database;
5> alter database open resetlogs;}

executing command: SET until clause

Starting restore at 20130705 11:01:14
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=25 device type=DISK

channel ORA_DISK_1: starting datafile backup set restore
          ......................
channel ORA_DISK_1: restored backup piece 1
channel ORA_DISK_1: restore complete, elapsed time: 00:00:55
Finished restore at 20130705 11:03:05

Starting recover at 20130705 11:03:06
using channel ORA_DISK_1

starting media recovery

archived log for thread 1 with sequence 27 is already on disk as file /u02/DB/oradb/arch/2013_07_05/o1_mf_1_27_8xd9c0f0_.arc
                .............................
archived log for thread 1 with sequence 31 is already on disk as file /u02/DB/oradb/arch/2013_07_05/o1_mf_1_31_8xdcg1wc_.arc
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_27_8xd9c0f0_.arc thread=1 sequence=27
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_28_8xdbcrht_.arc thread=1 sequence=28
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_29_8xdbnqx9_.arc thread=1 sequence=29
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_30_8xdbv338_.arc thread=1 sequence=30  --->该日志包含记录Jackson
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_31_8xdcg1wc_.arc thread=1 sequence=31 
media recovery complete, elapsed time: 00:00:10                              --->此时apply到了31(不包含sequence 31的内容)
Finished recover at 20130705 11:03:19

database opened

RMAN> host;

-->验证结果,记录Jackson已经被恢复
[oracle@node1 ~]$ ./query_t2.sh

ID        DT
---------- --------------------
Robinson  20130705 10:08:15
Jackson    20130705 10:11:27

c、基于sequence的不完全恢复
RMAN> shutdown immediate;
RMAN> startup mount;
RMAN> reset database to incarnation 2;
RMAN> run{
2> set until sequence 32;
3> restore database;
4> recover database;
5> alter database open resetlogs;}

executing command: SET until clause

Starting restore at 05-JUL-13
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=24 device type=DISK
              ...................
channel ORA_DISK_1: restore complete, elapsed time: 00:00:45
Finished restore at 05-JUL-13

Starting recover at 05-JUL-13
using channel ORA_DISK_1

starting media recovery
            ...................................
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_30_8xdbv338_.arc thread=1 sequence=30
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_31_8xdcg1wc_.arc thread=1 sequence=31 --->此时也是apply到了31
media recovery complete, elapsed time: 00:00:07                --->我们指定了sequence为32(但不包含sequence 32)
Finished recover at 05-JUL-13

database opened

RMAN> host;

Recovery Manager complete.

-->验证结果,记录Winson已经被恢复
[oracle@node1 ~]$ ./query_t2.sh

ID        DT
---------- --------------------
Robinson  20130705 10:08:15
Jackson    20130705 10:11:27
Winson    20130705 10:15:47

d、恢复到最近时刻
-->此处的恢复到最近(新)时刻,也就是我们希望恢复最后的记录"Completed"
-->通常情况下,我们恢复到故障点为完全恢复,此时也可以说是做完全恢复
-->但是由于我们对数据库作了不完全恢复,因此此时即使是做完全恢复,仍然为不完全恢复,见下面的示例
RMAN> shutdown immediate;
RMAN> startup mount;
RMAN> reset database to incarnation 2;
RMAN> run{
2> restore database;
3> recover database;
4> alter database open;}

Starting restore at 05-JUL-13
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=24 device type=DISK
            ...........................
channel ORA_DISK_1: restore complete, elapsed time: 00:00:45
Finished restore at 05-JUL-13

Starting recover at 05-JUL-13
using channel ORA_DISK_1

starting media recovery

archived log for thread 1 with sequence 27 is already on disk as file /u02/DB/oradb/arch/2013_07_05/o1_mf_1_27_8xd9c0f0_.arc
                            ......................
archived log for thread 1 with sequence 33 is already on disk as file /u02/DB/oradb/arch/2013_07_05/o1_mf_1_33_8xddbvsc_.arc
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_27_8xd9c0f0_.arc thread=1 sequence=27
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_28_8xdbcrht_.arc thread=1 sequence=28
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_29_8xdbnqx9_.arc thread=1 sequence=29
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_30_8xdbv338_.arc thread=1 sequence=30
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_31_8xdcg1wc_.arc thread=1 sequence=31
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_32_8xdcl0rx_.arc thread=1 sequence=32
archived log file name=/u02/DB/oradb/arch/2013_07_05/o1_mf_1_33_8xddbvsc_.arc thread=1 sequence=33
unable to find archived log
archived log thread=1 sequence=34
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of recover command at 07/05/2013 11:27:48
RMAN-06054: media recovery requesting unknown archived log for thread 1 with sequence 34 and starting SCN of 1367222

--可以看到,数据库被apply到了sequence为33的归档日志,现在数据库寻找sequence为34为SCN为1367222的归档日志
--细心的朋友可能会发现,我们之前仅仅归档到32,那sequence为33的归档日志从而而来呢,应该是系统自动产生了一次归档
--但这里我的归档日志大小为50MB,因此也不可能是由于redo log满而产生归档

--查看alert日志
[oracle@node1 trace]$ tail -1280 alert_oradb.log | more 
Media Recovery Log /u02/DB/oradb/arch/2013_07_05/o1_mf_1_29_8xdbnqx9_.arc
Fri Jul 05 10:35:41 2013
ORA-279 signalled during: alter database recover logfile '/u02/DB/oradb/arch/2013_07_05/o1_mf_1_29_8xdbnqx9_.arc'...
alter database recover logfile '/u02/DB/oradb/arch/2013_07_05/o1_mf_1_30_8xdbv338_.arc'
Media Recovery Log /u02/DB/oradb/arch/2013_07_05/o1_mf_1_30_8xdbv338_.arc
Incomplete Recovery applied until change 1365529 time 07/05/2013 10:09:59
Media Recovery Complete (oradb)    --->提示介质恢复完成
Completed: alter database recover logfile '/u02/DB/oradb/arch/2013_07_05/o1_mf_1_30_8xdbv338_.arc'
Fri Jul 05 10:37:15 2013
alter database open resetlogs      --->执行open resetlogs   
Archived Log entry 8 added for thread 1 sequence 33 ID 0x98733640 dest 1:  --->这个地方是关键
RESETLOGS after incomplete recovery UNTIL CHANGE 1365529
Resetting resetlogs activation ID 2557687360 (0x98733640) 
Errors in file /u01/app/oracle/diag/rdbms/oradb/oradb/trace/oradb_ora_30772.trc: 
ORA-00367: checksum error in log file header    --->下面伴随一堆重置日志文件前的ORA校验错误
ORA-00322: log 1 of thread 1 is not current copy
ORA-00312: online log 1 thread 1: '/u02/DB/oradb/redo/redo01.log'
Fri Jul 05 10:37:18 2013
Errors in file /u01/app/oracle/diag/rdbms/oradb/oradb/trace/oradb_m000_30963.trc:
ORA-00316: log 1 of thread 1, type 0 in header is not log file
ORA-00312: online log 1 thread 1: '/u02/DB/oradb/redo/redo01.log'
Errors in file /u01/app/oracle/diag/rdbms/oradb/oradb/trace/oradb_ora_30772.trc:
ORA-00367: checksum error in log file header
ORA-00322: log 2 of thread 1 is not current copy
ORA-00312: online log 2 thread 1: '/u02/DB/oradb/redo/redo02.log'
Errors in file /u01/app/oracle/diag/rdbms/oradb/oradb/trace/oradb_m000_30963.trc:
ORA-00316: log 2 of thread 1, type 0 in header is not log file
ORA-00312: online log 2 thread 1: '/u02/DB/oradb/redo/redo02.log'
Errors in file /u01/app/oracle/diag/rdbms/oradb/oradb/trace/oradb_ora_30772.trc:
ORA-00367: checksum error in log file header
ORA-00322: log 3 of thread 1 is not current copy
ORA-00312: online log 3 thread 1: '/u02/DB/oradb/redo/redo03.log'
Errors in file /u01/app/oracle/diag/rdbms/oradb/oradb/trace/oradb_m000_30963.trc:
ORA-00316: log 3 of thread 1, type 0 in header is not log file
ORA-00312: online log 3 thread 1: '/u02/DB/oradb/redo/redo03.log'
Fri Jul 05 10:37:23 2013
Setting recovery target incarnation to 3          --->设置新的incarnation

-->下面的归档日志的产生时间与alert日志中的时间相吻合
[oracle@node1 2013_07_05]$ ls -al --full-time o1_mf_1_33_8xddbvsc_.arc
-rw-r----- 1 oracle asmadmin 259584 2013-07-05 10:37:15.000000000 +0800 o1_mf_1_33_8xddbvsc_.arc

-->查询视图也可以得到在RESETLOGS时产生了归档日志
SQL> col name format a60 wrap
SQL> SELECT name,sequence# seq#,status,completion_time,end_of_redo_type eof_type from v$archived_log where sequence#=33;

NAME                                                              SEQ# S COMPLETION_TIME  EOF_TYPE
------------------------------------------------------------ ---------- - ----------------- ----------
/u02/database/oradb/flash_recovery_area/ORADB/archivelog/201        33 A 20130705 10:37:15 RESETLOGS
3_07_05/o1_mf_1_33_8xddbvsc_.arc

-->验证结果
SQL> alter database open resetlogs;

Database altered.

SQL> select * from scott.t2;

ID        DT
---------- --------------------
Robinson  20130705 10:08:15
Jackson    20130705 10:11:27
Winson    20130705 10:15:47
LastRecord 20130705 10:23:44
Completed  20130705 10:26:20

五、小结
a、RMAN支持基于TIME,SCN,SEQUENCE参数的不完全恢复,不支持基于CANCEL的不完全恢复
b、所有实施了不完全恢复的数据库都需要以open resetlogs方式打开数据库,且同时伴随一个新的incarnation产生
c、不完全恢复之后即使是恢复到故障点,或者说想做完全恢复,都只能是做不完全恢复到最近时刻
d、不完全恢复后再次恢复到最新时刻,新的incarnation变为CURRENT状态,中间的incarnation为ORPHAN状态
e、首次不完全恢复以open resetlogs方式打开数据库时,未归档的联机日志被归档
f、注意until子句的用法。until子句是到什么什么,不包括,是一个非半闭包的形式
g、生产环境建议不完全恢复前后备份数据库

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