Oracle bbed的使用(跨归档恢复)
正常情况下，数据库要打开则数据文件头的SCN号要和控制文件记录的一致（数据文件或表空间离线的情况例外），我们可以利用这个特性，通过修改数据文件头上SCN的方式来跨过相应归档实现不完全恢复，这种方法在非常规的恢复中可能会用到，当然最好还是从备份中恢复，提前做好备份方案，这样心里才有底，下面简单演示如果跨归档恢复，仅仅演示而已，希望生产环境中永远不会碰到。
1、 删除一个数据文件，查看相应SCN号
SQL> select name,status,checkpoint_change# from v$datafile_header;
NAME STATUS CHECKPOINT_CHANGE#
---------------------------------------------------------- ------------------
/u02/app/oracle/oradata/ora10g/system01.dbf ONLINE 1490772
/u02/app/oracle/oradata/ora10g/undotbs01.dbf ONLINE 1490772
/u02/app/oracle/oradata/ora10g/sysaux01.dbf ONLINE 1490772
ONLINE 0
可以看到数据文件已经丢失，下面从RMAN备份中还原一个但不做恢复
2、从RMAN备份中还原一个数据文件，但不做恢复
RMAN> restore datafile4;
Startingrestore at 12-8月 -13
allocatedchannel: ORA_DISK_1
channelORA_DISK_1: sid=155 devtype=DISK
channelORA_DISK_1: starting datafile backupset restore
channelORA_DISK_1: specifying datafile(s) to restore from backup set
restoringdatafile 00004 to /u02/app/oracle/oradata/ora10g/users01.dbf
channelORA_DISK_1: reading from backup piece /u01/backup/0doh4ghj_1_1.bkp
channelORA_DISK_1: restored backup piece 1
piecehandle=/u01/backup/0doh4ghj_1_1.bkp tag=TAG20130812T165619
channelORA_DISK_1: restore complete, elapsed time: 00:00:02
Finishedrestore at 12-8月 -13
再次查看数据文件头
SQL> select name,status,checkpoint_change# from v$datafile_header;
NAME STATUS CHECKPOINT_CHANGE#
---------------------------------------------------------- ------------------
/u02/app/oracle/oradata/ora10g/system01.dbf ONLINE 1490772
/u02/app/oracle/oradata/ora10g/undotbs01.dbf ONLINE 1490772
/u02/app/oracle/oradata/ora10g/sysaux01.dbf ONLINE 1490772
/u02/app/oracle/oradata/ora10g/users01.dbf ONLINE 1378511
现在打开数据库：
SQL> alter database open;
alterdatabase open
*
ERRORat line 1:
ORA-01113:file 4 needs media recovery if it was restored from backup, or END BACKUP if itwas not
ORA-01110:data file 4: '/u02/app/oracle/oradata/ora10g/users01.dbf'
SQL>recover database;##此时归档已经删除
ORA-00279:change 1378511 generated at 08/12/2013 16:56:19 needed for thread 1
ORA-00289:suggestion :
/u02/app/oracle/flash_recovery_area/ORA10G/archivelog/2013_08_12/o1_mf_1_54_%u_.arc
ORA-00280:change 1378511 for thread 1 is in sequence #54
Specifylog: {<RET>=suggested | filename | AUTO | CANCEL}
auto
ORA-00308:cannot open archived log
'/u02/app/oracle/flash_recovery_area/ORA10G/archivelog/2013_08_12/o1_mf_1_54_%u_.arc'
ORA-27037:unable to obtain file status
Linux-x86_64Error: 2: No such file or directory
Additionalinformation: 3
ORA-00308:cannot open archived log '/u02/app/oracle/flash_recovery_area/ORA10G/archivelog/2013_08_12/o1_mf_1_54_%u_.arc'
ORA-27037:unable to obtain file status
Linux-x86_64Error: 2: No such file or directory
Additionalinformation: 3
3、使用BBED修改4号文件头上的SCN号，使他和其他数据文件一致，然后再打开数据库
[oracle@hadoop1 bbed]$ bbed parfile=bbed.par
BBED:Release 2.0.0.0.0 - Limited Production on 星期一 8月12 21:50:52 2013
Copyright(c) 1982, 2007, Oracle. All rightsreserved.
*************!!! For Oracle Internal Use only !!! ***************
BBED> p dba 4,1 kcvfhckp
structkcvfhckp, 36 bytes @484
struct kcvcpscn, 8 bytes @484
ub4 kscnbas @484 0x001508cf
ub2 kscnwrp @488 0x0000
ub4 kcvcptim @492 0x31124233
ub2 kcvcpthr @496 0x0001
union u, 12 bytes @500
struct kcvcprba, 12 bytes @500
ub4 kcrbaseq @500 0x00000036
ub4 kcrbabno @504 0x00000002
ub2 kcrbabof @508 0x0010
ub1 kcvcpetb[0] @512 0x02
ub1 kcvcpetb[1] @513 0x00
ub1 kcvcpetb[2] @514 0x00
ub1 kcvcpetb[3] @515 0x00
ub1 kcvcpetb[4] @516 0x00
ub1 kcvcpetb[5] @517 0x00
ub1 kcvcpetb[6] @518 0x00
ub1 kcvcpetb[7] @519 0x00
BBED> p dba 2,1 kcvfhckp
structkcvfhckp, 36 bytes @484
struct kcvcpscn, 8 bytes @484
ub4kscnbas @484 0x0016bf54
ub2 kscnwrp @488 0x0000
ub4 kcvcptim @492 0x3112838f
ub2 kcvcpthr @496 0x0001
union u, 12 bytes @500
struct kcvcprba, 12 bytes @500
ub4 kcrbaseq @500 0x0000003c
ub4 kcrbabno @504 0x00000002
ub2 kcrbabof @508 0x0010
ub1 kcvcpetb[0] @512 0x02
ub1 kcvcpetb[1] @513 0x00
ub1 kcvcpetb[2] @514 0x00
ub1 kcvcpetb[3] @515 0x00
ub1 kcvcpetb[4] @516 0x00
ub1 kcvcpetb[5] @517 0x00
ub1 kcvcpetb[6] @518 0x00
ub1 kcvcpetb[7] @519 0x00
BBED> p dba 3,1kcvfhckp
struct kcvfhckp, 36 bytes @484
struct kcvcpscn, 8 bytes @484
ub4kscnbas @484 0x0016bf54
ub2 kscnwrp @488 0x0000
ub4 kcvcptim @492 0x3112838f
ub2 kcvcpthr @496 0x0001
union u, 12 bytes @500
struct kcvcprba, 12 bytes @500
ub4 kcrbaseq @500 0x0000003c
ub4 kcrbabno @504 0x00000002
ub2 kcrbabof @508 0x0010
ub1 kcvcpetb[0] @512 0x02
ub1 kcvcpetb[1] @513 0x00
ub1 kcvcpetb[2] @514 0x00
ub1 kcvcpetb[3] @515 0x00
ub1 kcvcpetb[4] @516 0x00
ub1 kcvcpetb[5] @517 0x00
ub1 kcvcpetb[6] @518 0x00
ub1 kcvcpetb[7] @519 0x00
可以看到4号文件SCN号所在位置
ub4kscnbas @484 0x001508cf
与2和3两个数据文件的SCN是不一样的
ub4kscnbas @484 0x0016bf54
ub4kscnbas @484 0x0016bf54
4、修改4号文件的SCN使其和其他数据文件一致
总共修改了三个地方：
ub4 kscnbas @484 0x0016bf54
ub4 kcvcptim @492 0x3112838f
ub4 kcrbaseq @500 0x0000003c
BBED> d /v dba 3,1 offset 484 count 10
File:/u02/app/oracle/oradata/ora10g/sysaux01.dbf (3)
Block: 1 Offsets: 484 to 493 Dba:0x00c00001
-------------------------------------------------------
54bf1600 00001e22 8f83 l T......"..
<16 bytes per line>
BBED> d /v dba 4,1 offset484 count 10
File:/u02/app/oracle/oradata/ora10g/users01.dbf (4)
Block: 1 Offsets: 484 to 493 Dba:0x01000001
-------------------------------------------------------
cf081500 00000000 3342 l ........3B
<16 bytes per line>
BBED> m /x 54bf1600 dba4,1 offset 484
Warning:contents of previous BIFILE will be lost. Proceed? (Y/N) Y
File:/u02/app/oracle/oradata/ora10g/users01.dbf (4)
Block: 1 Offsets: 484 to 493 Dba:0x01000001
------------------------------------------------------------------------
54bf1600 00000000 3342
<32 bytes per line>
BBED> d /v dba 4,1offset 484 count 10
File:/u02/app/oracle/oradata/ora10g/users01.dbf (4)
Block: 1 Offsets: 484 to 493 Dba:0x01000001
-------------------------------------------------------
54bf1600 00000000 3342 l T.......3B
<16 bytes per line>
BBED> d /v dba 3,1offset 484 count 10
File:/u02/app/oracle/oradata/ora10g/sysaux01.dbf (3)
Block: 1 Offsets: 484 to 493 Dba:0x00c00001
-------------------------------------------------------
54bf1600 00001e22 8f83 l T......"..
<16 bytes per line>
需要修改的地方还有：
ub4 kcvcptim @492 0x3112838f
BBED> m /x 8f83 dba 4,1 offset 492
Warning: contents ofprevious BIFILE will be lost. Proceed? (Y/N) Y
File: /u02/app/oracle/oradata/ora10g/users01.dbf(4)
Block: 1 Offsets: 492 to 501 Dba:0x01000001
------------------------------------------------------------------------
8f831231 01000000 3600
<32 bytes per line>
ub4 kcrbaseq @500 0x0000003c
BBED> m /x 3c00 dba 4,1 offset 500
File:/u02/app/oracle/oradata/ora10g/users01.dbf (4)
Block: 1 Offsets: 500 to 509 Dba:0x01000001
------------------------------------------------------------------------
3c000000 02000000 1000
<32 bytes per line>
BBED> sum apply
Check value for File3, Block 1:
current = 0x2f20,required = 0x2f20
BBED> exit
4、查看数据文件SCN号
SQL> select name,checkpoint_change# fromv$datafile_header;
NAME CHECKPOINT_CHANGE#
---------------------------------------------------------------
/u02/app/oracle/oradata/ora10g/system01.dbf 1490772
/u02/app/oracle/oradata/ora10g/undotbs01.dbf 1490772
/u02/app/oracle/oradata/ora10g/sysaux01.dbf 1490772
/u02/app/oracle/oradata/ora10g/users01.dbf 1490772
SQL> alter database open;
alter database open
*
ERRORat line 1:
ORA-01113:file 4 needs media recovery if it was restored from backup, or END
BACKUPif it was not
ORA-01110:data file 4: '/u02/app/oracle/oradata/ora10g/users01.dbf'
SQL>recover datafile 4;
Mediarecovery complete.
SQL> alter database open;
Databasealtered.
SQL>