我的java天地

Oracle backup&Restore(2)

第四章. 数据库恢复案例


4.1
非归档模式下的备份与恢复


备份方案:采用 OS 冷备份

 

1.  连接数据库并创建测试表

SQL> connect internal/password as sysdba;

Connected.

SQL> create table test(a int);

Table created

SQL> insert into test values(1);

1 row inserted

SQL> commit;

Commit complete

 

2.  备份数据库

SQL> @coldbak.sql 或在 DOS svrmgrl @coldbak.sql

 

3.  再插入记录

SQL> insert into test values(2);

1 row inserted

SQL> commit;

Commit complete

SQL> select * from test;

                         A

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

                         1

                         2

4.  关闭数据库

SQL> shutdown immediate;

Database closed.

Database dismounted.

Oracle instance shut down.

 

5.  毁坏一个或多个数据文件,如删除 user01.dbf

C:\>del D:\Oracle\ORADATA\TEST\USERS01.DBF

模拟媒体毁坏。

 

6.  重新启动数据库,会发现如下错误

SQL> startup

Oracle instance started.

 

Total System Global Area  102020364 bytes

Fixed Size                    70924 bytes

Variable Size              85487616 bytes

Database Buffers           16384000 bytes

Redo Buffers                  77824 bytes

Database mounted.

ORA-01157: cannot identify/lock data file 3 - see DBWR trace file

ORA-01110: data file 3: 'D:\Oracle\ORADATA\TEST\USERS01.DBF'

 

在报警文件中,会有更详细的信息

Errors in file D:\Oracle\admin\test\bdump\testDBW0.TRC:

ORA-01157: cannot identify/lock data file 3 - see DBWR trace file

ORA-01110: data file 3: 'D:\Oracle\ORADATA\TEST\USERS01.DBF'

ORA-27041: unable to open file

OSD-04002: unable to open file

O/S-Error: (OS 2) 系统找不到指定的文件。

 

7.  拷贝备份复原到原来位置 (restore 过程 )

C:\>xcopy d:\database\*.* d:\Oracle\oradata\test/H/R/S

 

8.  打开数据库,检查数据

SQL> alter database open;

Database altered.

SQL> select * from test;

                         A

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

                         1

 

这里可以发现,数据库恢复成功,但在备份之后与崩溃之前的数据丢失了。


说明:

1 、非归档模式下的恢复方案可选性很小,一般情况下只能有一种恢复方式,就是数据库的冷备
份的完全恢复,仅仅需要拷贝原来的备份就可以 (restore) ,不需要 recover

2 、这种情况下的恢复,可以完全恢复到备份的点上,但是可能是丢失数据的,在备份之后与崩溃之前的数据将全部丢失;

3 、不管毁坏了多少数据文件或是联机日志或是控制文件,都可以通过这个办法恢复,因为这个恢复过程是 Restore 所有的冷备份文件,而这个备份点上的所有文件是一致的,与最新的数据库没有关系,就好比把数据库又放到了一个以前的 " " 上;

4 、对于非归档模式下,最好的办法就是采用 OS 的冷备份,建议不要用 RMAN 来作冷备份,效果不好,因为 RMAN 不备份联机日志, restore 不能根本解决问题;

5 、如果没有备份联机日志,如 RMAN 的备份,就需要利用不完全恢复 (until cancel) 的方法来重新创建联机日志文件。


4.2 归档模式下丢失或损坏一个数据文件


4.2.1 OS 备份方案

在归档方式下损坏或丢失一个数据文件,如果存在相应的备份与该备份以来的归档日志,恢复还是比较简单的,可以作到尽量少的 Down 机时间,并能作到数据库的完全恢复。


1 连接数据库,创建测试表并插入记录

SQL> connect internal/password as sysdba;

Connected.

SQL> create table test(a int) tablespace users;

Table created

SQL> insert into test values(1);

1 row inserted

SQL> commit;

Commit complete

 

2 备份数据库

SQL> @hotbak.sql 或在 DOS svrmgrl @hotbak.sql

 

3 继续在测试表中插入记录

SQL> insert into test values(2);

1 row inserted

SQL> commit;

Commit complete

SQL> select * from test;

                         A

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

                         1

                         2

SQL> alter system switch logfile;

System altered.

SQL> alter system switch logfile;

System altered.

 

4 关闭数据库,模拟丢失数据文件

SQL> shutdown immediate;

Database closed.

Database dismounted.

Oracle instance shut down

C:\>del D:\Oracle\ORADATA\TEST\USERS01.DBF

模拟媒体毁坏。

 

5 启动数据库错误,脱机该数据文件:

SQL> startup

Oracle instance started.

 

Total System Global Area  102020364 bytes

Fixed Size                    70924 bytes

Variable Size              85487616 bytes

Database Buffers           16384000 bytes

Redo Buffers                  77824 bytes

Database mounted.

ORA-01157: cannot identify/lock data file 3 - see DBWR trace file

ORA-01110: data file 3: 'D:\Oracle\ORADATA\TEST\USERS01.DBF'


还可以查看报警文件(见上一个恢复案例)或动态视图 v$recover_file

SQL> select * from v$recover_file;

 

     FILE# ONLINE  ERROR                    CHANGE#    TIME

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

         3   ONLINE                        1013500    2003-05-07

 

脱机数据文件

SQL> alter database datafile 3 offline drop;

Database altered.

 

6 打开数据库,拷贝备份回来 (restore) ,恢复 (recover) 该数据文件,并联机 :


SQL> alter database open;

Database altered.


拷贝备份从备份处

copy d:\databak\ users01.dbf d:\Oracle\oradata\test;


恢复该数据文件

SQL> recover datafile 3;


ORA-00279: change 1053698 generated at 05/07/2003 17:51:26 needed for

thread 1

ORA-00289: suggestion :
D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00304.ARC

ORA-00280: change 1053698 for thread 1 is in sequence #304

 

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

AUTO

ORA-00279: change 1053701 generated at 05/07/2003 17:51:39 needed for

thread 1

ORA-00289: suggestion : D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00305.ARC

ORA-00280: change 1053701 for thread 1 is in sequence #305

ORA-00278: log file 'D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00304.ARC' no longer needed for this recovery Log applied.

Media recovery complete.


恢复成功,联机该数据文件

SQL> alter database datafile 3 online;

Database altered.

 

7 检查数据库的数据(完全恢复)

SQL> select * from test;

                         A

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

                         1

                         2

说明:

1 、采用热备份,需要运行在归档模式下,可以实现数据库的完全恢复,也就是说,从备份后到数据库崩溃时的数据都不会丢失 ;

2 、可以采用全备份数据库的方式备份,对于特殊情况,也可以只备份特定的数据文件,如只备份用户表空间(一般情况下对于某些写特别频繁的数据文件,可以单独加大备份频率);

3 、如果在恢复过程中,发现损坏的是多个数据文件,即可以采用一个一个数据文件的恢复方法(第 5 步中需要对数据文件一一脱机,第 6 步中需要对数据文件分别恢复),也可以采用整个数据库的恢复方法;

4 、如果是系统表空间的损坏,不能采用此方法。

 

4.2.2 RMAN 备份方案


RMAN 也可以进行联机备份,而且备份与恢复方法将比 OS 备份更简单可靠。

1 、连接数据库,创建测试表并插入记录

SQL> connect internal/password as sysdba;

Connected.

 

SQL> create table test(a int) tablespace users;

Table created

SQL> insert into test values(1);

1 row inserted

SQL> commit;

Commit complete

 

2 备份数据库表空间 users

C:\>rman

Recovery Manager: Release 8.1.6.0.0 - Production

RMAN> connect rcvcat rman/rman@back

RMAN-06008: connected to recovery catalog database

RMAN> connect target internal/virpure

RMAN-06005: connected to target database: TEST (DBID=1788174720)

 

RMAN> run{

2> allocate channel c1 type disk;

3> backup tag 'tsuser' format 'd:\backup\tsuser_%u_%s_%p'

4> tablespace users;

5> release channel c1;

6> }

 

RMAN-03022: compiling command: allocate

RMAN-03023: executing command: allocate

RMAN-08030: allocated channel: c1

RMAN-08500: channel c1: sid=16 devtype=DISK

 

RMAN-03022: compiling command: backup

RMAN-03025: performing implicit partial resync of recovery catalog

RMAN-03023: executing command: partial resync

RMAN-08003: starting partial resync of recovery catalog

RMAN-08005: partial resync complete

RMAN-03023: executing command: backup

RMAN-08008: channel c1: starting full datafile backupset

RMAN-08502: set_count=5 set_stamp=494177612 creation_time=16-MAY-03

RMAN-08010: channel c1: specifying datafile(s) in backupset

RMAN-08522: input datafile fno=00003 name=D:\Oracle\ORADATA\TEST\USER01.DBF

RMAN-08013: channel c1: piece 1 created

RMAN-08503: piece handle=D:\BACKUP\TSUSER_05EN93AC_5_1 comment=NONE

RMAN-08525: backup set complete, elapsed time: 00:00:01

RMAN-03023: executing command: partial resync

RMAN-08003: starting partial resync of recovery catalog

RMAN-08005: partial resync complete

RMAN-03022: compiling command: release

RMAN-03023: executing command: release

RMAN-08031: released channel: c1

RMAN>

 

3 继续在测试表中插入记录

SQL> insert into test values(2);

1 row inserted

SQL> commit;

Commit complete

SQL> select * from test;

                         A

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

                         1

                         2

SQL> alter system switch logfile;

System altered.

SQL>r

1* alter system switch logfile;

System altered.

 

4 关闭数据库,模拟丢失数据文件

SQL> shutdown immediate;

Database closed.

Database dismounted.

Oracle instance shut down

 

C:\>del D:\Oracle\ORADATA\TEST\USER01.DBF

 

5 启动数据库,检查错误

SQL> startup

Oracle instance started.

Total System Global Area  102020364 bytes

Fixed Size                    70924 bytes

Variable Size              85487616 bytes

Database Buffers           16384000 bytes

Redo Buffers                  77824 bytes

Database mounted.

ORA-01157: cannot identify/lock data file 3 - see DBWR trace file

ORA-01110: data file 3: 'D:\Oracle\ORADATA\TEST\USER01.DBF'

 

6 先打开数据库

SQL> alter database datafile 3 offline drop;

Database altered.

SQL> alter database open;

Database altered.

 

7 恢复该表空间

恢复脚本可以是恢复单个数据文件

run{

allocate channel c1 type disk;

restore datafile 3;

recover datafile 3;

sql 'alter database datafile 3 online';

release channel c1;

}

也可以是 , 恢复表空间

run{

allocate channel c1 type disk;

restore tablespace users;

recover tablespace users;

sql 'alter database datafile 3 online';

release channel c1;

}

过程如下:

C:\>rman

Recovery Manager: Release 8.1.6.0.0 - Production

RMAN> connect rcvcat rman/rman@back

RMAN-06008: connected to recovery catalog database

RMAN> connect target internal/virpure

RMAN-06005: connected to target database: TEST (DBID=1788174720)

 

RMAN> run{

2> allocate channel c1 type disk;

3> restore datafile 3;

4> recover datafile 3;

5> sql 'alter database datafile 3 online';

6> release channel c1;

7> }

 

// 输出内容冗长,省略 -- 编者

RMAN>

 

8 检查数据是否完整

SQL> alter database open;

Database altered.

 

SQL> select * from test;

                         A

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

                         1

                         2

说明:

1 RMAN 也可以实现单个表空间或数据文件的恢复,恢复过程可以在 mount 下或 open 方式下,如果在 open 方式下恢复,可以减少 down 机时间 ;

2 、如果损坏的是一个数据文件,建议 offline 并在 open 方式下恢复 ;

3 、这里可以看到, RMAN 进行数据文件与表空间恢复的时候,代码都比较简单,而且能保证备份与恢复的可靠性,所以建议采用 RMAN 的备份与恢复 .

 

4.3 丢失多个数据文件,实现整个数据库的恢复 .

 

4.3.1 OS 备份方案

OS 备份归档模式下损坏(丢失)多个数据文件,进行整个数据库的恢复

1 连接数据库,创建测试表并插入记录

SQL> connect internal/password as sysdba;

Connected.

 

SQL> create table test(a int);

Table created

SQL> insert into test values(1);

1 row inserted

SQL> commit;

Commit complete

 

2 备份数据库,备份除临时数据文件后的所数据文件

SQL> @hotbak.sql 或在 DOS svrmgrl @hotbak.sql

 

3 继续在测试表中插入记录

SQL> insert into test values(2);

1 row inserted

SQL> commit;

Commit complete

SQL> select * from test;

                         A

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

                         1

                         2

SQL> alter system switch logfile;

System altered.

SQL> alter system switch logfile;

System altered.

 

4 关闭数据库,模拟丢失数据文件

SQL> shutdown immediate;

Database closed.

Database dismounted.

Oracle instance shut down

 

C:\>del D:\Oracle\ORADATA\TEST\SYSTEM01.DBF

C:\>del D:\Oracle\ORADATA\TEST\INDX01.DBF

C:\>del D:\Oracle\ORADATA\TEST\TOOLS01.DBF

C:\>del D:\Oracle\ORADATA\TEST\RBS01.DBF

模拟媒体毁坏(这里删除多个数据文件)

 

5 启动数据库,检查错误

SQL> STARTUP

Oracle instance started.

Total System Global Area  102020364 bytes

Fixed Size                    70924 bytes

Variable Size              85487616 bytes

Database Buffers           16384000 bytes

Redo Buffers                  77824 bytes

Database mounted.

ORA-01157: cannot identify/lock data file 1 - see DBWR trace file

ORA-01110: data file 1: 'D:\Oracle\ORADATA\TEST\SYSTEM01.DBF'

 

详细信息可以查看报警文件

ORA-1157 signalled during: ALTER DATABASE OPEN...

Thu May 08 09:39:36 2003

Errors in file D:\Oracle\admin\test\bdump\testDBW0.TRC:

ORA-01157: cannot identify/lock data file 1 - see DBWR trace file

ORA-01110: data file 1: 'D:\Oracle\ORADATA\TEST\SYSTEM01.DBF'

ORA-27041: unable to open file

OSD-04002: unable to open file

O/S-Error: (OS 2) 系统找不到指定的文件。

 

Thu May 08 09:39:36 2003

Errors in file D:\Oracle\admin\test\bdump\testDBW0.TRC:

ORA-01157: cannot identify/lock data file 2 - see DBWR trace file

ORA-01110: data file 2: 'D:\Oracle\ORADATA\TEST\RBS01.DBF'

ORA-27041: unable to open file

OSD-04002: unable to open file

O/S-Error: (OS 2) 系统找不到指定的文件。

 

Thu May 08 09:39:36 2003

Errors in file D:\Oracle\admin\test\bdump\testDBW0.TRC:

ORA-01157: cannot identify/lock data file 5 - see DBWR trace file

ORA-01110: data file 5: 'D:\Oracle\ORADATA\TEST\TOOLS01.DBF'

ORA-27041: unable to open file

OSD-04002: unable to open file

O/S-Error: (OS 2) 系统找不到指定的文件。

 

Thu May 08 09:39:36 2003

Errors in file D:\Oracle\admin\test\bdump\testDBW0.TRC:

ORA-01157: cannot identify/lock data file 6 - see DBWR trace file

ORA-01110: data file 6: 'D:\Oracle\ORADATA\TEST\INDX01.DBF'

ORA-27041: unable to open file

OSD-04002: unable to open file

O/S-Error: (OS 2) 系统找不到指定的文件。

 

通过查询 v$recover_file 可以看到

SQL> select * from v$recover_file;

 

     FILE# ONLINE  ERROR                 CHANGE# TIME

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

         1 ONLINE  FILE NOT FOUND              0

         2 ONLINE  FILE NOT FOUND              0

         5 ONLINE  FILE NOT FOUND              0

         6 ONLINE  FILE NOT FOUND              0

有四个数据文件需要恢复

 

6 拷贝备份回到原地点 (restore) ,开始恢复数据库 (recover)

restore 过程 :

C:\>copy D:\DATABAK\SYSTEM01.DBF D:\Oracle\ORADATA\TEST\

C:\>copy D:\DATABAK\TEST\INDX01.DBF D:\Oracle\ORADATA\TEST\

C:\>copy D:\DATABAK\TEST\TOOLS01.DBF D:\Oracle\ORADATA\TEST\

C:\>copy D:\DATABAK\TEST\RBS01.DBF.DBF D:\Oracle\ORADATA\TEST\

 

Recover 过程 :

SQL> recover database [0001191]   ;

 

ORA-00279: change 1073849 generated at 05/08/2003 08:58:35 needed for thread 1

ORA-00289: suggestion : D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00311.ARC

ORA-00280: change 1073849 for thread 1 is in sequence #311

 

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

auto

ORA-00279: change 1073856 generated at 05/08/2003 09:03:27 needed for thread 1

ORA-00289: suggestion : D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00312.ARC

ORA-00280: change 1073856 for thread 1 is in sequence #312

ORA-00278: log file 'D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00311.ARC' no

longer needed for this recovery

 

ORA-00279: change 1073858 generated at 05/08/2003 09:11:43 needed for thread 1

ORA-00289: suggestion : D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00313.ARC

ORA-00280: change 1073858 for thread 1 is in sequence #313

ORA-00278: log file 'D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00312.ARC' no

longer needed for this recovery

 

ORA-00279: change 1073870 generated at 05/08/2003 09:11:46 needed for thread 1

ORA-00289: suggestion : D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00314.ARC

ORA-00280: change 1073870 for thread 1 is in sequence #314

ORA-00278: log file 'D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00313.ARC' no

longer needed for this recovery

 

Log applied.

Media recovery complete.

 

7 打开数据库,检查数据库的数据(完全恢复)

SQL> alter database open;

Database altered.

SQL> select * from test;

                         A

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

                         1

                         2

 

说明:

1 、只要有备份与归档存在,就可以实现数据库的完全恢复(不丢失数据) ;

2 、适合于丢失大量数据文件,或包含系统数据文件在内的数据库的恢复 ;

3 、恢复过程在 mount 下进行,如果恢复成功,再打开数据库, down 机时间可能比较长一些。

 

4.3.2 RMAN 备份方案

RMAN 备份归档模式下损坏(丢失)多个数据文件,进行整个数据库的恢复

1 、连接数据库,创建测试表并插入记录

 

SQL> connect internal/password as sysdba;

Connected.

SQL> create table test(a int);

Table created

SQL> insert into test values(1);

1 row inserted

SQL> commit;

Commit complete

 

2 、备份数据库

DOS C:>\ rman cmdfile=bakup.rcv msglog=backup.log;

 

以下是 backup.log 内容。

Recovery Manager: Release 8.1.6.0.0 - Production

RMAN> #     script:bakup.rcv

2> #     creater:chenjiping

3> #     date:5.8.2003

4> #     desc:backup all database datafile in archive with rman

5>

6> #connect database

7> connect rcvcat rman/rman@back;

8> connect target internal/virpure;

9>

10> #start backup database

11> run{

12> allocate channel c1 type disk;

13> backup full tag 'dbfull' format 'd:\backup\full%u_%s_%p' database

14> include current controlfile;

15> sql 'alter system archive log current';

16> release channel c1;

17> }

18> #end

19>

 

RMAN-06008: connected to recovery catalog database

RMAN-06005: connected to target database: TEST (DBID=1788174720)

RMAN-03022: compiling command: allocate

RMAN-03023: executing command: allocate

RMAN-08030: allocated channel: c1

RMAN-08500: channel c1: sid=15 devtype=DISK

RMAN-03022: compiling command: backup

RMAN-03023: executing command: backup

RMAN-08008: channel c1: starting full datafile backupset

RMAN-08502: set_count=4 set_stamp=494074368 creation_time=15-MAY-03

RMAN-08010: channel c1: specifying datafile(s) in backupset

RMAN-08522: input datafile fno=00002 name=D:\Oracle\ORADATA\TEST\RBS01.DBF

RMAN-08522: input datafile fno=00001 name=D:\Oracle\ORADATA\TEST\SYSTEM01.DBF

RMAN-08011: including current controlfile in backupset

RMAN-08522: input datafile fno=00005 name=D:\Oracle\ORADATA\TEST\TOOLS01.DBF

RMAN-08522: input datafile fno=00004 name=D:\Oracle\ORADATA\TEST\TEMP01.DBF

RMAN-08522: input datafile fno=00006 name=D:\Oracle\ORADATA\TEST\INDX01.DBF

RMAN-08522: input datafile fno=00003 name=D:\Oracle\ORADATA\TEST\USER01.DBF

RMAN-08013: channel c1: piece 1 created

RMAN-08503: piece handle=D:\BACKUP\FULL04EN5UG0_4_1 comment=NONE

RMAN-08525: backup set complete, elapsed time: 00:01:16

RMAN-03023: executing command: partial resync

RMAN-08003: starting partial resync of recovery catalog

RMAN-08005: partial resync complete

RMAN-03022: compiling command: sql

RMAN-06162: sql statement: alter system archive log current

RMAN-03023: executing command: sql

RMAN-03022: compiling command: release

RMAN-03023: executing command: release

RMAN-08031: released channel: c1

Recovery Manager complete.

到这里表示备份成功。

 

3 继续在测试表中插入记录

SQL> insert into test values(2);

1 row inserted

SQL> commit;

Commit complete

SQL> select * from test;

                         A

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

                         1

                         2

SQL>alter system switch logfile;

System altered.

SQL> alter system switch logfile;

System altered.

 

4 关闭数据库,模拟丢失数据文件

SQL> shutdown immediate;

Database closed.

Database dismounted.

Oracle instance shut down

C:\>del D:\Oracle\ORADATA\TEST\SYSTEM01.DBF

C:\>del D:\Oracle\ORADATA\TEST\INDX01.DBF

C:\>del D:\Oracle\ORADATA\TEST\TOOLS01.DBF

C:\>del D:\Oracle\ORADATA\TEST\RBS01.DBF

 

5 、启动数据库,检查错误

SQL> STARTUP

Oracle instance started.

Total System Global Area  102020364 bytes

Fixed Size                    70924 bytes

Variable Size              85487616 bytes

Database Buffers           16384000 bytes

Redo Buffers                  77824 bytes

Database mounted.

ORA-01157: cannot identify/lock data file 1 - see DBWR trace file

ORA-01110: data file 1: 'D:\Oracle\ORADATA\TEST\SYSTEM01.DBF'

 

查询 v$recover_file

SQL> select * from v$recover_file;

 

     FILE# ONLINE  ERROR                 CHANGE# TIME

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

         1 ONLINE  FILE NOT FOUND              0

         2 ONLINE  FILE NOT FOUND              0

         5 ONLINE  FILE NOT FOUND              0

         6 ONLINE  FILE NOT FOUND              0


可以知道有四个数据文件需要恢复 .

 

6 、利用 RMAN 进行恢复

C:\>rman

Recovery Manager: Release 8.1.6.0.0 - Production

RMAN> connect rcvcat rman/rman@back

RMAN-06008: connected to recovery catalog database

RMAN> connect target internal/virpure

RMAN-06005: connected to target database: TEST (DBID=1788174720)

RMAN> run{

2> allocate channel c1 type disk;

3> restore database;

4> recover database;

5> sql 'alter database open';

6> release channel c1;

7> }

 

RMAN-03022: compiling command: allocate

RMAN-03023: executing command: allocate

RMAN-08030: allocated channel: c1

RMAN-08500: channel c1: sid=17 devtype=DISK

RMAN-03022: compiling command: restore

RMAN-03025: performing implicit partial resync of recovery catalog

RMAN-03023: executing command: partial resync

RMAN-08003: starting partial resync of recovery catalog

RMAN-08005: partial resync complete

RMAN-03022: compiling command: IRESTORE

RMAN-03023: executing command: IRESTORE

RMAN-08016: channel c1: starting datafile backupset restore

RMAN-08502: set_count=4 set_stamp=494074368 creation_time=15-MAY-03

RMAN-08089: channel c1: specifying datafile(s) to restore from backup set

RMAN-08523: restoring datafile 00001 to D:\Oracle\ORADATA\TEST\SYSTEM01.DBF

RMAN-08523: restoring datafile 00002 to D:\Oracle\ORADATA\TEST\RBS01.DBF

RMAN-08523: restoring datafile 00003 to D:\Oracle\ORADATA\TEST\USER01.DBF

RMAN-08523: restoring datafile 00004 to D:\Oracle\ORADATA\TEST\TEMP01.DBF

RMAN-08523: restoring datafile 00005 to D:\Oracle\ORADATA\TEST\TOOLS01.DBF

RMAN-08523: restoring datafile 00006 to D:\Oracle\ORADATA\TEST\INDX01.DBF

RMAN-08023: channel c1: restored backup piece 1

RMAN-08511: piece handle=D:\BACKUP\FULL04EN5UG0_4_1 tag=DBFULL params=NULL

RMAN-08024: channel c1: restore complete

RMAN-03023: executing command: partial resync

RMAN-08003: starting partial resync of recovery catalog

RMAN-08005: partial resync complete

RMAN-03022: compiling command: recover

RMAN-03022: compiling command: recover(1)

RMAN-03022: compiling command: recover(2)

RMAN-03022: compiling command: recover(3)

RMAN-03023: executing command: recover(3)

RMAN-08054: starting media recovery

RMAN-03022: compiling command: recover(4)

RMAN-06050: archivelog thread 1 sequence 327 is already on disk as file D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00327.ARC

RMAN-06050: archivelog thread 1 sequence 328 is already on disk as file D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00328.ARC

RMAN-06050: archivelog thread 1 sequence 329 is already on disk as file D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00329.ARC

RMAN-06050: archivelog thread 1 sequence 330 is already on disk as file D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00330.ARC

RMAN-03023: executing command: recover(4)

RMAN-08515: archivelog filename=D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00327.ARC thread=1 sequence=327

RMAN-08515: archivelog filename=D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00328.ARC thread=1 sequence=328

RMAN-08055: media recovery complete

RMAN-03022: compiling command: sql

RMAN-06162: sql statement: alter database open

RMAN-03023: executing command: sql

RMAN-03022: compiling command: release

RMAN-03023: executing command: release

RMAN-08031: released channel: c1

RMAN>

 

7 检查数据库的数据(完全恢复)

SQL> select * from test;

                         A

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

                         1

                         2

 

说明:

1 、只要有备份与归档存在, RMAN 也可以实现数据库的完全恢复(不丢失数据) ;

2 、同 OS 备份数据库恢复,适合于丢失大量数据文件,或包含系统数据文件在内的数据库的恢复 ;

3 、目标数据库在 mount 下进行,如果恢复成功,再打开数据库 ;

4 RMAN 的备份与恢复命令相对比较简单并可靠,建议有条件的话,都采用 RMAN 进行数据库的备份。

 

4.4 不完全恢复案例

 

4.4.1 OS 备份下的基于时间的恢复

 

不完全恢复可以分为基于时间的恢复,基于改变的恢复与基于撤消的恢复,这里已基于时间的恢复为例子来说明不完全恢复过程。

 

基于时间的恢复可以不完全恢复到现在时间之前的某一个时间,对于某些误操作,如删除了一个数据表,可以在备用恢复环境上恢复到表的删除时间之前,然后把该表导出到正式环境,避免一个人为的错误。

 

1 连接数据库,创建测试表并插入记录 :

SQL> connect internal/password as sysdba;

Connected.

SQL> create table test(a int);

Table created

SQL> insert into test values(1);

1 row inserted

SQL> commit;

Commit complete

 

2 备份数据库,这里最好备份所有的数据文件,包括临时数据文件 :

SQL> @hotbak.sql 或在 DOS svrmgrl @hotbak.sql

或冷备份也可以

 

3 删除测试表,假定删除前的时间为 T1 ,在删除之前,便于测试,继续插入数据并应用到归  

档。

SQL> insert into test values(2);

1 row inserted

SQL> commit;

Commit complete

SQL> select * from test;

                         A

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

                         1

                         2

SQL> alter system switch logfile;

Statement processed.

SQL> alter system switch logfile;

Statement processed.

 

SQL> select to_char(sysdate,'yyyy-mm-dd hh24:mi:ss') from dual;

TO_CHAR(SYSDATE,'YY

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

2003-05-21 14:43:01

SQL> drop table test;

Table dropped.

 

4 准备恢复到时间点 T1 ,找回删除的表,先关闭数据库 :

SQL> shutdown immediate;

Database closed.

Database dismounted.

Oracle instance shut down.

 

5 拷贝刚才备份的所有数据文件回来

C:\>copy D:\DATABAK\*.DBF D:\Oracle\ORADATA\TEST\

 

6 启动到 mount

SQL> startup mount;

Oracle instance started.

Total System Global Area  102020364 bytes

Fixed Size                    70924 bytes

Variable Size              85487616 bytes

Database Buffers           16384000 bytes

Redo Buffers                  77824 bytes

Database mounted.

 

7 开始不完全恢复数据库到 T1 时间

SQL> recover database until time '2003-05-21:14:43:01';

ORA-00279: change 30944 generated at 05/21/2003 14:40:06 needed for thread 1

ORA-00289: suggestion : D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00191.ARC

ORA-00280: change 30944 for thread 1 is in sequence #191

 

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

auto

Log applied.

Media recovery complete.


8 打开数据库,检查数据

SQL> alter database open resetlogs;

 

Database altered.

SQL> select * from test;

                         A

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

                         1

                         2

 

说明:

1 、不完全恢复最好备份所有的数据,冷备份亦可,因为恢复过程是从备份点往后恢复的,如果因为其中一个数据文件的时间戳 (SCN) 大于要恢复的时间点,那么恢复都是不可能成功的 ;

2 、不完全恢复有三种方式,过程都一样,仅仅是 recover 命令有所不一样,这里用基于时间的恢复作为示例 ;

3 、不完全恢复之后,都必须用 resetlogs 的方式打开数据库,建议马上再做一次全备份,因为 resetlogs 之后再用以前的备份恢复是很难了 ;

4 、以上是在删除之前获得时间,但是实际应用中,很难知道删除之前的实际时间,但可以采用大致时间即可,或可以采用分析日志文件 (logmnr) ,取得精确的需要恢复的时间 ;

5 、一般都是在测试机后备用机器上采用这种不完全恢复,恢复之后导出 / 导入被误删的表回生产系统 .

 

4.4.2 RMAN 备份下的基于改变的恢复

以上用 OS 备份说明了一个基于时间的恢复,现在用 RMAN 说明一个基于改变的恢复

 

1 连接数据库,创建测试表并插入记录

 

SQL> connect internal/password as sysdba;

Connected.

SQL> create table test(a int);

Table created

SQL> insert into test values(1);

1 row inserted

SQL> commit;

Commit complete

 

2 备份数据库

C:\>rman

Recovery Manager: Release 8.1.6.0.0 - Production

RMAN> connect rcvcat rman/rman@back

RMAN-06008: connected to recovery catalog database

RMAN> connect target internal/virpure

RMAN-06005: connected to target database: TEST (DBID=874705288)

 

RMAN> run{

2> allocate channel c1 type disk;

3> backup full tag 'dbfull' format 'd:\backup\full%u_%s_%p' database

4> include current controlfile;

5> sql 'alter system archive log current';

6> release channel c1;

7> }

 

    // 屏幕输出内容冗长,省略 -- 编辑

RMAN>

 

3 删除测试表,在删除之前,便于测试,继续插入数据并应用到归档,并获取删除前的 scn 号。

SQL> insert into test values(2);

1 row inserted

SQL> commit;

Commit complete

SQL> select * from test;

                         A

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

                         1

                         2

SQL> alter system switch logfile;

Statement processed.

SQL> alter system switch logfile;

Statement processed.

 

SQL> select max(ktuxescnw * power(2, 32) + ktuxescnb) scn from x$ktuxe;

       SCN

----------

  31014

SQL> drop table test;

Table dropped.

 

4 准备恢复到 SCN 31014 ,先关闭数据库,然后启动到 mount

SQL> shutdown immediate;

Database closed.

Database dismounted.

Oracle instance shut down.

SQL> startup mount;

 

5 开始恢复到改变点 SCN 31014

RMAN> run{

2>      allocate channel c1 type disk;

3>      restore database;

4>      recover database until scn 31014;

5>      sql 'ALTER DATABASE OPEN RESETLOGS';

6>      release channel c1;

7> }

 

RMAN-03022: compiling command: allocate

RMAN-03023: executing command: allocate

RMAN-08030: allocated channel: c1

RMAN-08500: channel c1: sid=10 devtype=DISK

RMAN-03022: compiling command: restore

RMAN-03022: compiling command: IRESTORE

RMAN-03023: executing command: IRESTORE

RMAN-08016: channel c1: starting datafile backupset restore

RMAN-08502: set_count=1 set_stamp=494613682 creation_time=21-MAY-03

RMAN-08089: channel c1: specifying datafile(s) to restore from backup set

RMAN-08523: restoring datafile 00001 to D:\Oracle\ORADATA\TEST\SYSTEM01.DBF

RMAN-08523: restoring datafile 00002 to D:\Oracle\ORADATA\TEST\RBS01.DBF

RMAN-08523: restoring datafile 00003 to D:\Oracle\ORADATA\TEST\USERS01.DBF

RMAN-08523: restoring datafile 00004 to D:\Oracle\ORADATA\TEST\TEMP01.DBF

RMAN-08523: restoring datafile 00005 to D:\Oracle\ORADATA\TEST\TOOLS01.DBF

RMAN-08523: restoring datafile 00006 to D:\Oracle\ORADATA\TEST\INDX01.DBF

RMAN-08023: channel c1: restored backup piece 1

RMAN-08511: piece handle=D:\BACKUP\FULL01ENMD5I_1_1 tag=DBFULL params=NULL

RMAN-08024: channel c1: restore complete

RMAN-03023: executing command: partial resync

RMAN-08003: starting partial resync of recovery catalog

RMAN-08005: partial resync complete

RMAN-03022: compiling command: recover

RMAN-03022: compiling command: recover(1)

RMAN-03022: compiling command: recover(2)

RMAN-03022: compiling command: recover(3)

RMAN-03023: executing command: recover(3)

RMAN-08054: starting media recovery

RMAN-03022: compiling command: recover(4)

RMAN-06050: archivelog thread 1 sequence 191 is already on disk as file D:\ORACL

E\ORADATA\TEST\ARCHIVE\TESTT001S00191.ARC

RMAN-06050: archivelog thread 1 sequence 192 is already on disk as file D:\ORACL

E\ORADATA\TEST\ARCHIVE\TESTT001S00192.ARC

RMAN-03023: executing command: recover(4)

RMAN-08515: archivelog filename=D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00191.AR

C thread=1 sequence=191

RMAN-08515:archivelog filename=D:\Oracle\ORADATA\TEST\ARCHIVE\TESTT001S00192.ARC

Thread=1 sequence=192

RMAN-08055: media recovery complete

RMAN-03022: compiling command: sql

RMAN-06162: sql statement: ALTER DATABASE OPEN RESETLOGS

RMAN-03023: executing command: sql

RMAN-03022: compiling command: release

RMAN-03023: executing command: release

RMAN-08031: released channel: c1

 

6 检查数据

Database altered.

SQL> select * from test;

                         A

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

                         1

                         2

可以看到,表依然存在。

 

说明:

1 RMAN 也可以实现不完全恢复,方法比 OS 备份恢复的方法更简单可靠;

2 RMAN 可以基于时间,基于改变与基于日志序列的不完全恢复,基于日志序列的恢复可以指定恢复到哪个日志序列,如

run { 

        allocate channel ch1 type disk; 

        allocate channel ch2 type 'sbt_tape';

        set until logseq 1234 thread 1;

        restore controlfile to '$Oracle_HOME/dbs/cf1.f' ; 

        replicate controlfile from '$Oracle_HOME/dbs/cf1.f';

         alter database mount; 

        restore database; 

        recover database; 

        sql "ALTER DATABASE OPEN RESETLOGS";

}

3 与所有的不完全恢复一样,必须在 mount 下, restore 所有备份数据文件,需要 resetlogs

4 基于改变的恢复比基于时间的恢复更可靠,但是可能也更复杂,需要知道需要恢复到哪一个改变号 (SCN) ,在正常生产中,获取 SCN 的办法其实也有很多,如查询数据库字典表 (V$archived_log or v$log_history) ,或分析归档与联机日志 (logmnr)

posted on 2009-05-07 21:33 tobyxiong 阅读(1635) 评论(0)  编辑  收藏 所属分类: DATABASES


只有注册用户登录后才能发表评论。


网站导航:
 
<2009年5月>
262728293012
3456789
10111213141516
17181920212223
24252627282930
31123456

导航

统计

常用链接

留言簿(3)

随笔分类(144)

随笔档案(157)

相册

最新随笔

搜索

积分与排名

最新评论

阅读排行榜

评论排行榜