dbv检测，dd块恢复

湖北佛

sys@OMREP> select segment_name,tablespace_id,header_file,header_block from sys_dba_segs where segment_name='T';

SEGMENT_NAME                                                                      TABLESPACE_ID HEADER_FILE HEADER_BLOCK
--------------------------------------------------------------------------------- ------------- ----------- ------------
T                                                                                             4           4        21578

sys@OMREP> !dbv segment_id=4.4.21578 userid=scott/tiger

DBVERIFY: Release 11.2.0.1.0 - Production on Wed Sep 4 15:17:39 2013

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

DBVERIFY - Verification starting : SEGMENT_ID = 4.4.21578


DBVERIFY - Verification complete

Total Pages Examined         : 256
Total Pages Processed (Data) : 244
Total Pages Failing   (Data) : 0
Total Pages Processed (Index): 0
Total Pages Failing   (Index): 0
Total Pages Processed (Other): 11
Total Pages Processed (Seg)  : 1
Total Pages Failing   (Seg)  : 0
Total Pages Empty            : 0
Total Pages Marked Corrupt   : 0
Total Pages Influx           : 0
Total Pages Encrypted        : 0
Highest block SCN            : 1928594 (0.1928594)

冷备份，dd逐块恢复
sys@OMREP> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.

[oracle@localhost omrep]$ dd of=users01.dbf bs=8192 conv=notrunc seek=21578 <<EOF
corrupt me
EOF
0+1 records in
0+1 records out
11 bytes (11 B) copied, 8.0791e-05 s, 136 kB/s

sys@OMREP> startup
ORACLE instance started.

Total System Global Area  422670336 bytes
Fixed Size                  1336960 bytes
Variable Size             335546752 bytes
Database Buffers           79691776 bytes
Redo Buffers                6094848 bytes
Database mounted.
Database opened.
sys@OMREP> select count(*) from scott.t;
select count(*) from scott.t
                           *
ERROR at line 1:
ORA-01578: ORACLE data block corrupted (file # 4, block # 21578)
ORA-01110: data file 4: '/u01/app/oracle/oradata/omrep/users01.dbf'

[oracle@localhost omrep]$ dd if=users01.bak of=users01.dbf bs=8192 count=1 conv=notrunc skip=21578 seek=21578      
1+0 records in
1+0 records out
8192 bytes (8.2 kB) copied, 0.000132787 s, 61.7 MB/s

sys@OMREP> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
sys@OMREP> startup
ORACLE instance started.

Total System Global Area  422670336 bytes
Fixed Size                  1336960 bytes
Variable Size             335546752 bytes
Database Buffers           79691776 bytes
Redo Buffers                6094848 bytes
Database mounted.
Database opened.

sys@OMREP> select count(*) from scott.t;

  COUNT(*)
----------
     13281

如果数据文件老的，之前数据有更新怎么办，还需要测试，

sys@OMREP> !dbv file=/u01/app/oracle/oradata/omrep/users01.dbf feedback=1000;

DBVERIFY: Release 11.2.0.1.0 - Production on Wed Sep 4 08:54:23 2013

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

DBVERIFY - Verification starting : FILE = /u01/app/oracle/oradata/omrep/users01.dbf
.......................

DBVERIFY - Verification complete

Total Pages Examined         : 22560
Total Pages Processed (Data) : 20644
Total Pages Failing   (Data) : 0
Total Pages Processed (Index): 50
Total Pages Failing   (Index): 0
Total Pages Processed (Other): 513
Total Pages Processed (Seg)  : 0
Total Pages Failing   (Seg)  : 0
Total Pages Empty            : 1353
Total Pages Marked Corrupt   : 0
Total Pages Influx           : 0
Total Pages Encrypted        : 0
Highest block SCN            : 1896412 (0.1896412)