不完全恢复之--基于时间恢复

探索ORACLE不完全恢复之--基于时间恢复

作者：吴伟龙 Name：Prodence Woo

QQ：286507175 msn:[e-mail]

基于时间（time）恢复

基于时间的恢复将数据库恢复到备份点与失败点之间的某个时间点。基于时间的恢复不仅在介质失败的时候使用，也可以在数据库正常运行的时候使用。例如：某个用户误删除了某个表的数据，这个时候我们可以通过基于时间的恢复来将删除的数据恢复出来，示例如下：

1、查看当前用户下的表，只有一张WWL001

21:07:31 SQL> select * from tab;

TNAME TABTYPE CLUSTERID

------------------------------ -----------------

WWL001 TABLE

Elapsed: 00:00:00.06

我们通过WWL001来创建WWL002-WWL005 共四张表用来测试不完全恢复

21:08:28 SQL> create table wwl002 asselect * from wwl001;

Table created.

Elapsed: 00:00:00.17

21:08:55 SQL> create table wwl003 asselect * from wwl001;

Table created.

Elapsed: 00:00:00.04

21:09:00 SQL> create table wwl004 asselect * from wwl001;

Table created.

Elapsed: 00:00:00.03

21:09:06 SQL> create table wwl005 asselect * from wwl001;

Table created.

Elapsed: 00:00:00.05

如上表已经创建完成

2、我们在21:13:13开始删除表（请注意时间）

21:13:13 SQL> drop table wwl002 purge;

Table dropped.

Elapsed: 00:00:00.16

21:13:28 SQL> drop table wwl003 purge;

Table dropped.

Elapsed: 00:00:00.11

21:13:34 SQL> truncate table wwl004;

Table truncated.

Elapsed: 00:00:00.32

21:13:44 SQL> truncate table wwl005;

Table truncated.

Elapsed: 00:00:00.07

21:13:47 SQL>

因为我们是要做基于时间的恢复，那么我们只有将数据库恢复到21:13:13之前的这个时间段，才能把我们刚才创建的表找回来。

3、开始执行恢复，先将数据库启动到mount状态

21:14:40 SQL> conn / as sysdba

Connected.

21:14:44 SQL> shutdown immediate

Database closed.

Database dismounted.

ORACLE instance shut down.

21:15:20 SQL> startup mount;

ORACLE instance started.

Total System Global Area 100663296 bytes

Fixed Size 1217884 bytes

Variable Size 88083108 bytes

Database Buffers 8388608 bytes

Redo Buffers 2973696 bytes

Database mounted.

21:15:46 SQL> e

4、开始执行restore到备份数据库的当前状态：

RMAN> restore database;

Starting restore at 12-JUL-12

using target database control file insteadof recovery catalog

allocated channel: ORA_DISK_1

channel ORA_DISK_1: sid=47 devtype=DISK

channel ORA_DISK_1: starting datafilebackupset restore

channel ORA_DISK_1: specifying datafile(s)to restore from backup set

restoring datafile 00001 to/DBBak2/oradata/WWL/system01.dbf

restoring datafile 00002 to/DBBak2/oradata/WWL/undotbs01.dbf

restoring datafile 00003 to/DBBak2/oradata/WWL/sysaux01.dbf

restoring datafile 00004 to/DBBak2/oradata/WWL/users01.dbf

restoring datafile 00005 to/DBBak2/oradata/WWL/wwl01.dbf

restoring datafile 00006 to/DBBak2/oradata/WWL/wwl02.dbf

restoring datafile 00007 to/DBBak2/oradata/WWL/wwl03.dbf

channel ORA_DISK_1: reading from backuppiece /DBSoft/product/10.2.0/db_1/dbs/01nft4mu_1_1

channel ORA_DISK_1: restored backup piece1

piecehandle=/DBSoft/product/10.2.0/db_1/dbs/01nft4mu_1_1 tag=TAG20120712T095437

channel ORA_DISK_1: restore complete,elapsed time: 00:01:35

Finished restore at 12-JUL-12

RMAN> exit

5、执行基于时间点的恢复：

21:27:54 SQL> recover database untiltime ‘YYYY-mm-dd hh24:mi:ss’

21:27:54 SQL> recover database untiltime '2012-07-12 21:10:00';

ORA-00279: change 1436429 generated at07/12/2012 09:54:38 needed for thread 1

ORA-00289: suggestion :/DBSoft/product/10.2.0/db_1/dbs/arch1_3_788372282.dbf

ORA-00280: change 1436429 for thread 1 isin sequence #3

21:30:09 Specify log:{<RET>=suggested | filename | AUTO | CANCEL}

auto

ORA-00279: change 1440657 generated at 07/12/201214:00:52 needed for thread 1

ORA-00289: suggestion :/DBSoft/product/10.2.0/db_1/dbs/arch1_1_788450452.dbf

ORA-00280: change 1440657 for thread 1 isin sequence #1

ORA-00279: change 1440855 generated at07/12/2012 15:08:58 needed for thread 1

ORA-00289: suggestion :/DBSoft/product/10.2.0/db_1/dbs/arch1_1_788454538.dbf

ORA-00280: change 1440855 for thread 1 isin sequence #1

ORA-00279: change 1441316 generated at07/12/2012 15:19:50 needed for thread 1

ORA-00289: suggestion : /DBSoft/product/10.2.0/db_1/dbs/arch1_1_788455190.dbf

ORA-00280: change 1441316 for thread 1 isin sequence #1

ORA-00279: change 1442275 generated at07/12/2012 15:52:01 needed for thread 1

ORA-00289: suggestion :/DBSoft/product/10.2.0/db_1/dbs/arch1_1_788457121.dbf

ORA-00280: change 1442275 for thread 1 isin sequence #1

ORA-00279: change 1442953 generated at07/12/2012 16:25:06 needed for thread 1

ORA-00289: suggestion :/DBSoft/product/10.2.0/db_1/dbs/arch1_1_788459106.dbf

ORA-00280: change 1442953 for thread 1 is insequence #1

ORA-00279: change 1462958 generated at07/12/2012 16:28:16 needed for thread 1

ORA-00289: suggestion :/DBSoft/product/10.2.0/db_1/dbs/arch1_2_788459106.dbf

ORA-00280: change 1462958 for thread 1 isin sequence #2

ORA-00278: log file '/DBSoft/product/10.2.0/db_1/dbs/arch1_1_788459106.dbf'no longer needed for this recovery

ORA-00279: change 1462963 generated at07/12/2012 17:17:59 needed for thread 1

ORA-00289: suggestion :/DBSoft/product/10.2.0/db_1/dbs/arch1_1_788462279.dbf

ORA-00280: change 1462963 for thread 1 isin sequence #1

ORA-00279: change 1483784 generated at07/12/2012 17:54:25 needed for thread 1

ORA-00289: suggestion :/DBSoft/product/10.2.0/db_1/dbs/arch1_2_788462279.dbf

ORA-00280: change 1483784 for thread 1 isin sequence #2

ORA-00278: log file'/DBSoft/product/10.2.0/db_1/dbs/arch1_1_788462279.dbf' no longer needed forthis recovery

Log applied.

Media recovery complete.

21:30:29 SQL>

至此已经恢复完成。

6、因为做了不完全恢复，必须要做restlogs打开数据库。

21:30:29 SQL> alter database open restlogs;

alter database open restlogs

7、数据已经恢复完成，数据都回来了。

21:34:04 SQL> select * from wwl002;

ID NAME

-------------------------------------------------------

1 wwl

2 prodence

3 woo

4 xgx

5 cms

Elapsed: 00:00:00.01

21:34:16 SQL> select * from wwl003;

ID NAME

-------------------------------------------------------

1 wwl

2 prodence

3 woo

4 xgx

5 cms

Elapsed: 00:00:00.00

21:34:18 SQL> select * from wwl004;

ID NAME

-------------------------------------------------------

1 wwl

2 prodence

3 woo

4 xgx

5 cms

Elapsed: 00:00:00.01

21:34:20 SQL> select * from wwl005;

ID NAME

---------- ---------------------------------------------

1 wwl

2 prodence

3 woo

4 xgx

5 cms

Elapsed: 00:00:00.01

21:34:22 SQL>