rman制造坏块,bbed修复坏块

在rman中有隐藏的命令clear,可以标记数据块为corrupt,从而实现数据库坏块试验,本篇blog通过dbv,bbed,table select来验证坏块的出现和修复
创建测试表

SQL>  create table t_xifenfei as
  2   select object_id,object_name from dba_objects where rownum<10;
Table created.
SQL>  select rowid,
  2   dbms_rowid.rowid_relative_fno(rowid) rel_fno,
  3   dbms_rowid.rowid_block_number(rowid) block
  4   from chf.t_xifenfei;
ROWID                 REL_FNO      BLOCK
------------------ ---------- ----------
AAAStAAAEAAAACrAAA          4        171
AAAStAAAEAAAACrAAB          4        171
AAAStAAAEAAAACrAAC          4        171
AAAStAAAEAAAACrAAD          4        171
AAAStAAAEAAAACrAAE          4        171
AAAStAAAEAAAACrAAF          4        171
AAAStAAAEAAAACrAAG          4        171
AAAStAAAEAAAACrAAH          4        171
AAAStAAAEAAAACrAAI          4        171
9 rows selected.
SQL> alter system checkpoint;
System altered.

dbv验证坏块

[oracle@xifenfei ~]$ dbv file=/u01/oracle/oradata/ora11g/users01.dbf
DBVERIFY: Release 11.2.0.3.0 - Production on Sun Jan 20 09:12:16 2013
Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved.
DBVERIFY - Verification starting : FILE = /u01/oracle/oradata/ora11g/users01.dbf
DBVERIFY - Verification complete
Total Pages Examined         : 7680
Total Pages Processed (Data) : 3776
Total Pages Failing   (Data) : 0
Total Pages Processed (Index): 167
Total Pages Failing   (Index): 0
Total Pages Processed (Other): 744
Total Pages Processed (Seg)  : 0
Total Pages Failing   (Seg)  : 0
Total Pages Empty            : 2993
Total Pages Marked Corrupt   : 0
Total Pages Influx           : 0
Total Pages Encrypted        : 0
Highest block SCN            : 1006717955 (2956.1006717955)

这里创建了t_xifenfei表,数据存储在file 4 block 171中,现在该block一切正常,本试验就是要通过rman来使得该block corrupt,然后通过bbed来修复

bbed查看kcbh

BBED> set block 171
        BLOCK#          171
BBED> p kcbh
struct kcbh, 20 bytes                       @0
   ub1 type_kcbh                            @0        0x06
   ub1 frmt_kcbh                            @1        0xa2
   ub1 spare1_kcbh                          @2        0x00
   ub1 spare2_kcbh                          @3        0x00
   ub4 rdba_kcbh                            @4        0x010000ab
   ub4 bas_kcbh                             @8        0x3c014bfe
   ub2 wrp_kcbh                             @12       0x0b8c
   ub1 seq_kcbh                             @14       0x02
   ub1 flg_kcbh                             @15       0x04 (KCBHFCKV)
   ub2 chkval_kcbh                          @16       0x6e0c  <--重点关注
   ub2 spare3_kcbh                          @18       0x0000

rman标记坏块

RMAN> BLOCKRECOVER DATAFILE 4 block 171 clear;
Starting recover at 20-JAN-13
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=18 device type=DISK
Finished recover at 20-JAN-13

dbv再次检查坏块

[oracle@xifenfei ~]$ dbv file=/u01/oracle/oradata/ora11g/users01.dbf
DBVERIFY: Release 11.2.0.3.0 - Production on Sun Jan 20 09:53:16 2013
Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved.
DBVERIFY - Verification starting : FILE = /u01/oracle/oradata/ora11g/users01.dbf
Page 171 is marked corrupt
Corrupt block relative dba: 0x010000ab (file 4, block 171)
Bad check value found during dbv:
Data in bad block:
 type: 6 format: 2 rdba: 0x010000ab
 last change scn: 0x0b8c.3c014bfe seq: 0x2 flg: 0x04
 spare1: 0x0 spare2: 0x0 spare3: 0x0
 consistency value in tail: 0x4bfe0602
 check value in block header: 0x6e0c
 computed block checksum: 0xb5bc
DBVERIFY - Verification complete
Total Pages Examined         : 7680
Total Pages Processed (Data) : 3775
Total Pages Failing   (Data) : 0
Total Pages Processed (Index): 167
Total Pages Failing   (Index): 0
Total Pages Processed (Other): 744
Total Pages Processed (Seg)  : 0
Total Pages Failing   (Seg)  : 0
Total Pages Empty            : 2993
Total Pages Marked Corrupt   : 1
Total Pages Influx           : 1
Total Pages Encrypted        : 0
Highest block SCN            : 1006717955 (2956.1006717955)

尝试查询数据

SQL> select count(*) from t_xifenfei;
select count(*) from t_xifenfei
                     *
ERROR at line 1:
ORA-01578: ORACLE data block corrupted (file # 4, block # 171)
ORA-01110: data file 4: '/u01/oracle/oradata/ora11g/users01.dbf'

bbed验证坏块

BBED> set block 171
        BLOCK#          171
BBED> p kcbh
struct kcbh, 20 bytes                       @0
   ub1 type_kcbh                            @0        0x06
   ub1 frmt_kcbh                            @1        0xa2
   ub1 spare1_kcbh                          @2        0x00
   ub1 spare2_kcbh                          @3        0x00
   ub4 rdba_kcbh                            @4        0x010000ab
   ub4 bas_kcbh                             @8        0x3c014bfe
   ub2 wrp_kcbh                             @12       0x0b8c
   ub1 seq_kcbh                             @14       0x02
   ub1 flg_kcbh                             @15       0x04 (KCBHFCKV)
   ub2 chkval_kcbh                          @16       0x6e0c  <--注意该值未变化
   ub2 spare3_kcbh                          @18       0x0000
BBED> verify
DBVERIFY - Verification starting
FILE = /u01/oracle/oradata/ora11g/users01.dbf
BLOCK = 171
Block 171 is corrupt
Corrupt block relative dba: 0x010000ab (file 0, block 171)
Bad check value found during verification
Data in bad block:
 type: 6 format: 2 rdba: 0x010000ab
 last change scn: 0x0b8c.3c014bfe seq: 0x2 flg: 0x04
 spare1: 0x0 spare2: 0x0 spare3: 0x0
 consistency value in tail: 0x4bfe0602
 check value in block header: 0x6e0c
 computed block checksum: 0xb5bc
DBVERIFY - Verification complete
Total Blocks Examined         : 1
Total Blocks Processed (Data) : 0
Total Blocks Failing   (Data) : 0
Total Blocks Processed (Index): 0
Total Blocks Failing   (Index): 0
Total Blocks Empty            : 0
Total Blocks Marked Corrupt   : 1
Total Blocks Influx           : 0
Message 531 not found;  product=RDBMS; facility=BBED

这里通过dbv,bbed,select table都证明rman能够标记block为Corrupt.
这里需要分析:block已经被标记,那证明该块肯定有修改,也就是说chkval_kcbh一定要变化,但是这里没有变化,证明该处异常

bbed修复rman生成坏块

BBED> sum apply
Warning: contents of previous BIFILE will be lost. Proceed? (Y/N) y
Check value for File 0, Block 171:
current = 0xdbb0, required = 0xdbb0
BBED> verify
DBVERIFY - Verification starting
FILE = /u01/oracle/oradata/ora11g/users01.dbf
BLOCK = 171
DBVERIFY - Verification complete
Total Blocks Examined         : 1
Total Blocks Processed (Data) : 1
Total Blocks Failing   (Data) : 0
Total Blocks Processed (Index): 0
Total Blocks Failing   (Index): 0
Total Blocks Empty            : 0
Total Blocks Marked Corrupt   : 0
Total Blocks Influx           : 0
Message 531 not found;  product=RDBMS; facility=BBED

bbed测试坏块已经修复

dbv验证坏块

[oracle@xifenfei ~]$ dbv file=/u01/oracle/oradata/ora11g/users01.dbf
DBVERIFY: Release 11.2.0.3.0 - Production on Sun Jan 20 10:01:46 2013
Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved.
DBVERIFY - Verification starting : FILE = /u01/oracle/oradata/ora11g/users01.dbf
DBVERIFY - Verification complete
Total Pages Examined         : 7680
Total Pages Processed (Data) : 3776
Total Pages Failing   (Data) : 0
Total Pages Processed (Index): 167
Total Pages Failing   (Index): 0
Total Pages Processed (Other): 744
Total Pages Processed (Seg)  : 0
Total Pages Failing   (Seg)  : 0
Total Pages Empty            : 2993
Total Pages Marked Corrupt   : 0
Total Pages Influx           : 0
Total Pages Encrypted        : 0
Highest block SCN            : 1006717955 (2956.1006717955)

dbv测试坏块也被修复

查询表验证

SQL> select count(*) from t_xifenfei;
  COUNT(*)
----------
         9

数据也可以正常查询,证明rman的坏块问题通过bbed解决

总结说明
1.我们可以通过rman的clear命令来标记坏块(BLOCKRECOVER DATAFILE file# BLOCK block1#, block2#, block3#… CLEAR 😉
2.我们可以通过bbed的sum apply命令来修复该类型坏块

ORA-600 kghstack_free2异常恢复

今天接触一案例ORA-00600[kghstack_free2],恢复起来很简单,顺便记录下，供其他人遇到类似情况参考.

Wed Feb 20 15:05:04 2013
SMON: enabling cache recovery
Wed Feb 20 15:05:05 2013
Successfully onlined Undo Tablespace 1.
Wed Feb 20 15:05:05 2013
SMON: enabling tx recovery
Wed Feb 20 15:05:06 2013
Errors in file f:\oracle\product\10.2.0\admin\cksoltp\bdump\cksoltp_smon_3556.trc:
ORA-00600: internal error code, arguments: [kghstack_free2], [], [], [], [], [], [], []
Wed Feb 20 15:05:06 2013
Database Characterset is AL32UTF8
replication_dependency_tracking turned off (no async multimaster replication found)
Wed Feb 20 15:05:08 2013
Errors in file f:\oracle\product\10.2.0\admin\cksoltp\bdump\cksoltp_smon_3556.trc:
ORA-07445: exception encountered: core dump [ACCESS_VIOLATION] [_kghstack_err+101]
[PC:0x603CC77F] [ADDR:0x59004E04] [UNABLE_TO_READ] []
ORA-00600: internal error code, arguments: [kghstack_free2], [], [], [], [], [], [], []
Starting background process QMNC
QMNC started with pid=18, OS id=3504
Wed Feb 20 15:05:13 2013
Errors in file f:\oracle\product\10.2.0\admin\cksoltp\bdump\cksoltp_pmon_4064.trc:
ORA-00474: SMON process terminated with error

这个错误很明显是因为smon在回滚事务的时候，遇到异常从而出现ORA-00600[kghstack_free2]错误，使得数据库不能被正常open，通过分析trace文件发现回滚段36中有事务未提交，需要回滚，针对这样的数据库恢复方法很简单:1.屏蔽事务回滚，2.屏蔽回滚段强制offline等
1) EVENT=”10513 trace name context forever”
2）_offline_rollback_segments= _SYSSMU36$
数据库启动后，通过分析trace文件，找出来异常对象，然后重建该对象,除掉event/_offline_rollback_segments即可

通过rowid获取segment header坏块数据

在上篇(table中各种坏块对select/dml操作影响)中说到如果segment header异常了，不能通过ctas来获得相关数据，在群的讨论中，EZIO说到可以通过rowid方式来获得相关数据，通过测试证明，确实可以通过该方法获得数据，以后遇到此类错误，大家也不必惊慌.
创建测试表

SQL> create table t_xifenfei
  2  as
  3  select * from dba_objects where object_id is not null;
SQL> alter table t_xifenfei
  2  add constraint PK_t_xifenfei primary key (object_id)
  3  ;
Table altered.
SQL> alter system checkpoint;
System altered.
SQL> select count(*) from chf.t_xifenfei;
  COUNT(*)
----------
     74762
SQL> select header_file,header_block from
  2  DBA_SEGments where segment_name='T_XIFENFEI' AND OWNER='CHF';
HEADER_FILE HEADER_BLOCK
----------- ------------
          4          170

dump block

alter system dump datafile 4 block 170;
Dump of buffer cache at level 4 for tsn=4 rdba=16777386
Block dump from disk:
buffer tsn: 4 rdba: 0x010000aa (4/170)
scn: 0x0b8c.3c0092e4 seq: 0x01 flg: 0x04 tail: 0x91e42301
frmt: 0x02 chkval: 0xa531 type: 0x23=PAGETABLE SEGMENT HEADER

通过header_block和dump block确定block 170即为PAGETABLE SEGMENT HEADER

bbed制造SEGMENT HEADER坏块

BBED> set block 170
        BLOCK#          170
BBED> set offset 8188
        OFFSET          8188
BBED> d
 File: /u01/oracle/oradata/ora11g/users01.dbf (0)
 Block: 170              Offsets: 8188 to 8191           Dba:0x00000000
------------------------------------------------------------------------
 0123e492
 <32 bytes per line>
BBED> m /x 0123e491
Warning: contents of previous BIFILE will be lost. Proceed? (Y/N) y
 File: /u01/oracle/oradata/ora11g/users01.dbf (0)
 Block: 170              Offsets: 8188 to 8191           Dba:0x00000000
------------------------------------------------------------------------
 0123e491
 <32 bytes per line>
BBED> sum apply
Check value for File 0, Block 170:
current = 0xa531, required = 0xa531
BBED> verify
DBVERIFY - Verification starting
FILE = /u01/oracle/oradata/ora11g/users01.dbf
BLOCK = 170
Block 170 is corrupt
Corrupt block relative dba: 0x010000aa (file 0, block 170)
Fractured block found during verification
Data in bad block:
 type: 35 format: 2 rdba: 0x010000aa
 last change scn: 0x0b8c.3c0092e4 seq: 0x1 flg: 0x04
 spare1: 0x0 spare2: 0x0 spare3: 0x0
 consistency value in tail: 0x91e42301
 check value in block header: 0xa531
 computed block checksum: 0x0
DBVERIFY - Verification complete
Total Blocks Examined         : 1
Total Blocks Processed (Data) : 0
Total Blocks Failing   (Data) : 0
Total Blocks Processed (Index): 0
Total Blocks Failing   (Index): 0
Total Blocks Empty            : 0
Total Blocks Marked Corrupt   : 1
Total Blocks Influx           : 2
Message 531 not found;  product=RDBMS; facility=BBED

测试segment header坏块后select操作

SQL> select * from chf.t_xifenfei;
select * from chf.t_xifenfei
                         *
ERROR at line 1:
ORA-01578: ORACLE data block corrupted (file # 4, block # 170)
ORA-01110: data file 4: '/u01/oracle/oradata/ora11g/users01.dbf'
SQL> select /*+index(t PK_T_XIFENFEI)*/  count(rowid) from chf.t_xifenfei t;
COUNT(ROWID)
------------
       74762

基于rowid获取segment header 坏块对象数据

SQL> create table chf.bad_rows (table_name varchar2(60),
   2 row_id rowid, oracle_error_code number);
Table created.
SQL> DECLARE
  2   TYPE RowIDTab IS TABLE OF ROWID INDEX BY BINARY_INTEGER;
  3   CURSOR c1 IS  select /*+index(t PK_T_XIFENFEI)*/ rowid from chf.t_xifenfei t;
  4   r RowIDTab;
  5   rows  NATURAL := 20000;
  6   bad_rows number := 0 ;
  7   errors number;
  8   error_code number;
  9   myrowid rowid;
 10  BEGIN
 11   OPEN c1;
 12   LOOP
 13     FETCH  c1 BULK COLLECT INTO r LIMIT rows;
 14     EXIT WHEN r.count=0;
 15     BEGIN
 16      FORALL i IN r.FIRST..r.LAST SAVE EXCEPTIONS
 17       insert into chf.t_xifenfei_new
 18       select /*+ ROWID(A) */ *
 19       from chf.t_xifenfei A where rowid = r(i);
 20     EXCEPTION
 21     when OTHERS then
 22      BEGIN
 23       errors := SQL%BULK_EXCEPTIONS.COUNT;
 24       FOR err1 IN 1..errors LOOP
 25           error_code := SQL%BULK_EXCEPTIONS(err1).ERROR_CODE;
 26           myrowid := r(SQL%BULK_EXCEPTIONS(err1).ERROR_INDEX);
 27           bad_rows := bad_rows + 1;
 28           insert into chf.bad_rows values('chf.t_xifenfei',myrowid, error_code);
 29       END LOOP;
 30       END;
 31     END;
 32    commit;
 33   END LOOP;
 34   commit;
 35   CLOSE c1;
 36   dbms_output.put_line('Total Bad Rows: '||bad_rows);
 37  END;
 38  /
Total Bad Rows: 0
PL/SQL procedure successfully completed.
SQL> select count(*) from chf.t_xifenfei_new;
  COUNT(*)
----------
     74762

通过上面pl/sql，基于rowid成功获得segment header 异常对象中的所有数据记录.如果没有主键的表出现该问题,可以参考:使用plsql抢救数据

table中各种坏块对select/dml操作影响

在春节前写过table中各种类型block坏块是否能被跳过,本来准备节前写完它的姊妹篇关于table中各种blog如果出现坏块,对select/dml操作影响,因为回家一些事情给耽误了,今天补上该文章,这篇文章主要基于试验测试为主,没有从相关block原理上进行分析,如果有时间,后续文章从原理上来分析为什么这些select/dml操作不能执行
创建测试表

SQL> create table t_xifenfei as
  2  select * from dba_objects where rownum<10;
Table created.
SQL> select count(*) from chf.t_xifenfei;
  COUNT(*)
----------
         9
SQL> select
  2  dbms_rowid.rowid_relative_fno(rowid)rel_fno,
  3       max(dbms_rowid.rowid_block_number(rowid)) max_block,
  4       min(dbms_rowid.rowid_block_number(rowid)) min_block
  5       from chf.t_xifenfei
  6       group by dbms_rowid.rowid_relative_fno(rowid);
   REL_FNO  MAX_BLOCK  MIN_BLOCK
---------- ---------- ----------
         4        171        171
SQL> select EXTENT_ID,FILE_ID,BLOCK_ID,blocks from dba_extents where owner='CHF'
  2   AND SEGMENT_NAME='T_XIFENFEI';
 EXTENT_ID    FILE_ID   BLOCK_ID     BLOCKS
---------- ---------- ---------- ----------
         0          4        168          8
SQL> select SEGMENT_NAME,HEADER_FILE,HEADER_BLOCK,blocks,extents from DBA_SEGMENTS
  2  WHERE OWNER='CHF' AND SEGMENT_NAME='T_XIFENFEI';
SEGMENT_NAME                   HEADER_FILE HEADER_BLOCK     BLOCKS    EXTENTS
------------------------------ ----------- ------------ ---------- ----------
T_XIFENFEI                               4          170          8          1

通过alter system dump datafile 4 block n得出相关block数据块类型
168为FIRST LEVEL BITMAP BLOCK
169为SECOND LEVEL BITMAP BLOCK
170为PAGETABLE SEGMENT HEADER
171为trans data

处理block 168

--制造坏块
BBED> set block 168
        BLOCK#          168
BBED> set offset 8188
        OFFSET          8188
BBED> d
 File: /u01/oracle/oradata/ora11g/users01.dbf (0)
 Block: 168              Offsets: 8188 to 8191           Dba:0x00000000
------------------------------------------------------------------------
 0320d14f
 <32 bytes per line>
BBED> m /x 0320d14e
Warning: contents of previous BIFILE will be lost. Proceed? (Y/N) y
 File: /u01/oracle/oradata/ora11g/users01.dbf (0)
 Block: 168              Offsets: 8188 to 8191           Dba:0x00000000
------------------------------------------------------------------------
 0320d14e
 <32 bytes per line>
BBED> sum apply
Check value for File 0, Block 168:
current = 0xf60b, required = 0xf60b
BBED> verify
DBVERIFY - Verification starting
FILE = /u01/oracle/oradata/ora11g/users01.dbf
BLOCK = 168
Block 168 is corrupt
Corrupt block relative dba: 0x010000a8 (file 0, block 168)
Fractured block found during verification
Data in bad block:
 type: 32 format: 2 rdba: 0x010000a8
 last change scn: 0x0b8c.3bff4fd1 seq: 0x3 flg: 0x04
 spare1: 0x0 spare2: 0x0 spare3: 0x0
 consistency value in tail: 0x4ed12003
 check value in block header: 0xf60b
 computed block checksum: 0x0
DBVERIFY - Verification complete
Total Blocks Examined         : 1
Total Blocks Processed (Data) : 0
Total Blocks Failing   (Data) : 0
Total Blocks Processed (Index): 0
Total Blocks Failing   (Index): 0
Total Blocks Empty            : 0
Total Blocks Marked Corrupt   : 1
Total Blocks Influx           : 2
Message 531 not found;  product=RDBMS; facility=BBED
--select操作
SQL> select count(*) from chf.t_xifenfei;
  COUNT(*)
----------
         9
--dml操作
SQL> delete from chf.t_xifenfei where rownum<3;
2 rows deleted.
----注意update操作
SQL> update chf.t_xifenfei set object_name='www.xifenfei.com';
7 rows updated.
SQL> insert into chf.t_xifenfei select * from dba_objects where rownum=1;
insert into chf.t_xifenfei select * from dba_objects where rownum=1
                *
ERROR at line 1:
ORA-01578: ORACLE data block corrupted (file # 4, block # 168)
ORA-01110: data file 4: '/u01/oracle/oradata/ora11g/users01.dbf'

这里证明对于FIRST LEVEL BITMAP BLOCK,在delete,select操作正常，insert操作异常，update操作待定(update操作不一定能够立马展示效果)

处理block 169

--标记坏块
BBED> set block 169
        BLOCK#          169
BBED> set offset 8188
        OFFSET          8188
BBED> d
 File: /u01/oracle/oradata/ora11g/users01.dbf (0)
 Block: 169              Offsets: 8188 to 8191           Dba:0x00000000
------------------------------------------------------------------------
 0221ce4f
 <32 bytes per line>
BBED> m /x 0221ce4e
Warning: contents of previous BIFILE will be lost. Proceed? (Y/N) y
 File: /u01/oracle/oradata/ora11g/users01.dbf (0)
 Block: 169              Offsets: 8188 to 8191           Dba:0x00000000
------------------------------------------------------------------------
 0221ce4e
 <32 bytes per line>
BBED> sum apply
Check value for File 0, Block 169:
current = 0x9d2f, required = 0x9d2f
BBED> verify
DBVERIFY - Verification starting
FILE = /u01/oracle/oradata/ora11g/users01.dbf
BLOCK = 169
Block 169 is corrupt
Corrupt block relative dba: 0x010000a9 (file 0, block 169)
Fractured block found during verification
Data in bad block:
 type: 33 format: 2 rdba: 0x010000a9
 last change scn: 0x0b8c.3bff4fce seq: 0x2 flg: 0x04
 spare1: 0x0 spare2: 0x0 spare3: 0x0
 consistency value in tail: 0x4ece2102
 check value in block header: 0x9d2f
 computed block checksum: 0x0
DBVERIFY - Verification complete
Total Blocks Examined         : 1
Total Blocks Processed (Data) : 0
Total Blocks Failing   (Data) : 0
Total Blocks Processed (Index): 0
Total Blocks Failing   (Index): 0
Total Blocks Empty            : 0
Total Blocks Marked Corrupt   : 1
Total Blocks Influx           : 2
Message 531 not found;  product=RDBMS; facility=BBED
--select操作
SQL> select count(*) from chf.t_xifenfei;
  COUNT(*)
----------
         9
--dml操作
SQL> delete from chf.t_xifenfei where rownum<2;
1 row deleted.
----注意update操作
SQL> update chf.t_xifenfei set object_name='www.xifenfei.com';
9 rows updated.
SQL> alter table t_xifenfei modify EDITION_NAME varchar2(4000);
Table altered.
SQL> update t_xifenfei set EDITION_NAME=lpad('www.xifenfei.com', 4000, '0');
update t_xifenfei set EDITION_NAME=lpad('www.xifenfei.com', 4000, '0')
       *
ERROR at line 1:
ORA-01578: ORACLE data block corrupted (file # 4, block # 169)
ORA-01110: data file 4: '/u01/oracle/oradata/ora11g/users01.dbf'
SQL> insert into chf.t_xifenfei
  2  select * from dba_objects where rownum<2;
insert into chf.t_xifenfei
                *
ERROR at line 1:
ORA-01578: ORACLE data block corrupted (file # 4, block # 169)
ORA-01110: data file 4: '/u01/oracle/oradata/ora11g/users01.dbf'

SECOND LEVEL BITMAP BLOCK在delete,select操作正常，insert操作异常，update操作分情况(如果更新的列字符串交短，可能不报错，如果更新的字符串较长可能报错)

处理block 170

--标记坏块
BBED> SET BLOCK 170
        BLOCK#          170
BBED> set offset 8188
        OFFSET          8188
BBED> d
 File: /u01/oracle/oradata/ora11g/users01.dbf (0)
 Block: 170              Offsets: 8188 to 8191           Dba:0x00000000
------------------------------------------------------------------------
 0223b91b
 <32 bytes per line>
BBED> m /x  0223b91a
 File: /u01/oracle/oradata/ora11g/users01.dbf (0)
 Block: 170              Offsets: 8188 to 8191           Dba:0x00000000
------------------------------------------------------------------------
 0223b91a
 <32 bytes per line>
BBED> sum apply
Check value for File 0, Block 170:
current = 0xb7d4, required = 0xb7d4
BBED> verify
DBVERIFY - Verification starting
FILE = /u01/oracle/oradata/ora11g/users01.dbf
BLOCK = 170
Block 170 is corrupt
Corrupt block relative dba: 0x010000aa (file 0, block 170)
Fractured block found during verification
Data in bad block:
 type: 35 format: 2 rdba: 0x010000aa
 last change scn: 0x0b8c.3c001bb9 seq: 0x2 flg: 0x04
 spare1: 0x0 spare2: 0x0 spare3: 0x0
 consistency value in tail: 0x1ab92302
 check value in block header: 0xb7d4
 computed block checksum: 0x0
DBVERIFY - Verification complete
Total Blocks Examined         : 1
Total Blocks Processed (Data) : 0
Total Blocks Failing   (Data) : 0
Total Blocks Processed (Index): 0
Total Blocks Failing   (Index): 0
Total Blocks Empty            : 0
Total Blocks Marked Corrupt   : 1
Total Blocks Influx           : 2
Message 531 not found;  product=RDBMS; facility=BBED
--select操作
SQL> select count(*) from chf.t_xifenfei;
select count(*) from chf.t_xifenfei
                         *
ERROR at line 1:
ORA-01578: ORACLE data block corrupted (file # 4, block # 170)
ORA-01110: data file 4: '/u01/oracle/oradata/ora11g/users01.dbf'
--dml操作
SQL> update chf.t_xifenfei where object_name='www.xifenfei.com';
update chf.t_xifenfei where object_name='www.xifenfei.com'
                      *
ERROR at line 1:
ORA-00971: missing SET keyword
SQL> update chf.t_xifenfei set object_name='www.xifenfei.com';
update chf.t_xifenfei set object_name='www.xifenfei.com'
           *
ERROR at line 1:
ORA-01578: ORACLE data block corrupted (file # 4, block # 170)
ORA-01110: data file 4: '/u01/oracle/oradata/ora11g/users01.dbf'
SQL> delete from chf.t_xifenfei where rownum<2;
delete from chf.t_xifenfei where rownum<2
                *
ERROR at line 1:
ORA-01578: ORACLE data block corrupted (file # 4, block # 170)
ORA-01110: data file 4: '/u01/oracle/oradata/ora11g/users01.dbf'

PAGETABLE SEGMENT HEADER异常的时候，数据库包括select,update,delete,insert操作都不能进行

结果汇总
1.BITMAP BLOCK异常的时候，select/delete操作可以正常进行，insert操作异常，update操作可能异常也可能正常
2.SEGMENT HEADER异常的时候，数据库包括select,update,delete,insert操作都不能进行
3.对于这些特殊的block出现坏块，如果有rman备份，从10g开始可以通过rman blockrecover来修复
4.如果没有rman备份,可以BITMAP BLOCK可以类似ctas重建,SEGMENT HEADER可以通过dul scan extent抽取数据
5.对于trans data太过于常见，而且event就可以跳过,在以前的文章中说过，不再讲述

dul处理分区表

创建SALES分区表案例

CREATE TABLE SALES
(
  PRODUCT_ID VARCHAR2(5),
  SALES_DATE DATE,
  SALES_COST NUMBER(10),
  STATUS VARCHAR2(20)
)
PARTITION BY RANGE(SALES_DATE)
  SUBPARTITION BY LIST (STATUS)
  SUBPARTITION TEMPLATE
  (
    SUBPARTITION SUB1 VALUES ('ACTIVE') ,
    SUBPARTITION SUB2 VALUES ('INACTIVE')
  )
(
  PARTITION P1 VALUES LESS THAN (TO_DATE('2003-01-01','YYYY-MM-DD')),
  PARTITION P2 VALUES LESS THAN (TO_DATE('2003-03-01','YYYY-MM-DD'))
)
/
INSERT INTO SALES VALUES('00001','01-Jan-02',100,'ACTIVE')
/
INSERT INTO SALES VALUES('00002','01-Jan-01',200,'ACTIVE')
/
INSERT INTO SALES VALUES('00003','01-Feb-03',300,'INACTIVE')
/
INSERT INTO SALES VALUES('00004','04-Feb-03',300,'INACTIVE')
/
INSERT INTO SALES VALUES('00005','04-Feb-02',300,'INACTIVE')
/

查询结果

SQL> select * from sales;
PRODU SALES_DATE   SALES_COST STATUS
----- ------------ ---------- --------------------
00001 01-JAN-02           100 ACTIVE
00002 01-JAN-01           200 ACTIVE
00005 04-FEB-02           300 INACTIVE
00003 01-FEB-03           300 INACTIVE
00004 04-FEB-03           300 INACTIVE
SQL> select  * from sales PARTITION(p1);
PRODU SALES_DATE   SALES_COST STATUS
----- ------------ ---------- --------------------
00001 01-JAN-02           100 ACTIVE
00002 01-JAN-01           200 ACTIVE
00005 04-FEB-02           300 INACTIVE
SQL> select  * from sales PARTITION(p2);
PRODU SALES_DATE   SALES_COST STATUS
----- ------------ ---------- --------------------
00003 01-FEB-03           300 INACTIVE
00004 04-FEB-03           300 INACTIVE
SQL> select  * from sales SUBPARTITION(p1_sub1);
PRODU SALES_DATE   SALES_COST STATUS
----- ------------ ---------- --------------------
00001 01-JAN-02           100 ACTIVE
00002 01-JAN-01           200 ACTIVE
SQL> select  * from sales SUBPARTITION(p1_sub2);
PRODU SALES_DATE   SALES_COST STATUS
----- ------------ ---------- --------------------
00005 04-FEB-02           300 INACTIVE
SQL> select  * from sales SUBPARTITION(p2_sub1);
no rows selected
SQL> select  * from sales SUBPARTITION(p2_sub2);
PRODU SALES_DATE   SALES_COST STATUS
----- ------------ ---------- --------------------
00003 01-FEB-03           300 INACTIVE
00004 04-FEB-03           300 INACTIVE

启动dul

[oracle@xifenfei dul]$ ./dul
Data UnLoader: 10.2.0.5.20 - Internal Only - on Sat Jan 19 17:37:45 2013
with 64-bit io functions
Copyright (c) 1994 2013 Bernard van Duijnen All rights reserved.
 Strictly Oracle Internal Use Only
DUL: Warning: Recreating file "dul.log"
Reading USER.dat 91 entries loaded
Reading OBJ.dat 74764 entries loaded and sorted 74764 entries
Reading TAB.dat 2882 entries loaded
Reading COL.dat 94598 entries loaded and sorted 94598 entries
Reading SEG.dat 17 entries loaded
Reading EXT.dat 43 entries loaded and sorted 43 entries
Reading TABPART.dat 150 entries loaded and sorted 150 entries
Reading TABCOMPART.dat 3 entries loaded and sorted 3 entries
Reading TABSUBPART.dat 36 entries loaded and sorted 36 entries
Reading INDPART.dat 169 entries loaded and sorted 169 entries
Reading INDCOMPART.dat 0 entries loaded and sorted 0 entries
Reading INDSUBPART.dat 0 entries loaded and sorted 0 entries
Reading IND.dat 5150 entries loaded
Reading LOB.dat
DUL: Warning: Increased the size of DC_LOBS from 1024 to 8192 entries
 1286 entries loaded
Reading ICOL.dat 7569 entries loaded
Reading COLTYPE.dat 3003 entries loaded
Reading TYPE.dat 2872 entries loaded
Reading ATTRIBUTE.dat 11127 entries loaded
Reading COLLECTION.dat 985 entries loaded
Reading COMPATSEG.dat 0 entries loaded
Reading BOOTSTRAP.dat 60 entries loaded
Reading LOBFRAG.dat 1 entries loaded and sorted 1 entries
Reading LOBCOMPPART.dat 0 entries loaded and sorted 0 entries
Reading UNDO.dat 21 entries loaded
Reading TS.dat 10 entries loaded
Reading PROPS.dat 36 entries loaded
Database character set is ZHS16GBK
Database national character set is AL16UTF16
Found db_id = 4188950066
Found db_name = ORA11G

unload 语法

UNLOAD [TABLE]  [  schema_name . ]  table_name
              [ PARTITION(  partition_name ) ]
              [ SUBPARTITION(  sub_partition_name ) ]
              [ (  column_definitions ) ]
              [  cluster_clause  ]
              [  storage_clause  ] ;

unload整个表

DUL> unload table chf.SALES;
. unloading table                     SALES
 . Unloading partition                      P1
 .   Unloading sub partition                 P1_SUB1
 .   Unloading sub partition                 P1_SUB2
 . Unloading partition                      P2
 .   Unloading sub partition                 P2_SUB1
 .   Unloading sub partition                 P2_SUB2
.           table SALES total        5 rows unloaded
[root@xifenfei dul]# ls -l CHF_SALES*
-rw-r--r-- 1 oracle oinstall 421 Jan 19 18:09 CHF_SALES.ctl
-rw-r--r-- 1 oracle oinstall 251 Jan 19 18:09 CHF_SALES.dat
[root@xifenfei dul]# more CHF_SALES.dat
|00001| |01-JAN-2002 AD 00:00:00| |100| |ACTIVE|
|00002| |01-JAN-2001 AD 00:00:00| |200| |ACTIVE|
|00005| |04-FEB-2002 AD 00:00:00| |300| |INACTIVE|
|00003| |01-FEB-2003 AD 00:00:00| |300| |INACTIVE|
|00004| |04-FEB-2003 AD 00:00:00| |300| |INACTIVE|

unload 分区表

DUL> unload table chf.SALES PARTITION(p1);
. unloading table                     SALES
 . Unloading partition                      P1
 .   Unloading sub partition                 P1_SUB1
 .   Unloading sub partition                 P1_SUB2
.           table SALES total        3 rows unloaded
[root@xifenfei dul]# ls -l CHF_SALES_P1*
-rw-r--r-- 1 oracle oinstall 424 Jan 19 18:10 CHF_SALES_P1.ctl
-rw-r--r-- 1 oracle oinstall 149 Jan 19 18:10 CHF_SALES_P1.dat
[root@xifenfei dul]# more CHF_SALES_P1.dat
|00001| |01-JAN-2002 AD 00:00:00| |100| |ACTIVE|
|00002| |01-JAN-2001 AD 00:00:00| |200| |ACTIVE|
|00005| |04-FEB-2002 AD 00:00:00| |300| |INACTIVE|

unload 子分区表

DUL> unload table chf.SALES SUBPARTITION(p2_SUB2);
. unloading table                     SALES
 . Unloading partition                      P1
 . Unloading partition                      P2
 .   Unloading sub partition                 P2_SUB2
.           table SALES total        2 rows unloaded
[root@xifenfei dul]# ls -l CHF_SALES_P2_SUB2*
-rw-r--r-- 1 oracle oinstall 429 Jan 19 18:14 CHF_SALES_P2_SUB2.ctl
-rw-r--r-- 1 oracle oinstall 102 Jan 19 18:14 CHF_SALES_P2_SUB2.dat
[root@xifenfei dul]# more CHF_SALES_P2_SUB2.dat
|00003| |01-FEB-2003 AD 00:00:00| |300| |INACTIVE|
|00004| |04-FEB-2003 AD 00:00:00| |300| |INACTIVE|

验证控制文件

[root@xifenfei dul]# ls -l CHF_SALES*
-rw-r--r-- 1 oracle oinstall 421 Jan 19 18:09 CHF_SALES.ctl
-rw-r--r-- 1 oracle oinstall 251 Jan 19 18:09 CHF_SALES.dat
-rw-r--r-- 1 oracle oinstall 424 Jan 19 18:10 CHF_SALES_P1.ctl
-rw-r--r-- 1 oracle oinstall 149 Jan 19 18:10 CHF_SALES_P1.dat
-rw-r--r-- 1 oracle oinstall 429 Jan 19 18:14 CHF_SALES_P2_SUB2.ctl
-rw-r--r-- 1 oracle oinstall 102 Jan 19 18:14 CHF_SALES_P2_SUB2.dat
[root@xifenfei dul]# more CHF_SALES.ctl
load data
CHARACTERSET ZHS16GBK
infile 'CHF_SALES.dat'
insert
into table "CHF"."SALES"
fields terminated by whitespace
(
  "PRODUCT_ID"                       CHAR(5) enclosed by X'7C'
 ,"SALES_DATE"                       DATE "DD-MON-YYYY AD HH24:MI:SS" enclosed by X'7C'
 ,"SALES_COST"                       CHAR(3) enclosed by X'7C'
 ,"STATUS"                           CHAR(8) enclosed by X'7C'
)
[root@xifenfei dul]# more CHF_SALES_P1.ctl
load data
CHARACTERSET ZHS16GBK
infile 'CHF_SALES_P1.dat'
insert
into table "CHF"."SALES"
fields terminated by whitespace
(
  "PRODUCT_ID"                       CHAR(5) enclosed by X'7C'
 ,"SALES_DATE"                       DATE "DD-MON-YYYY AD HH24:MI:SS" enclosed by X'7C'
 ,"SALES_COST"                       CHAR(3) enclosed by X'7C'
 ,"STATUS"                           CHAR(8) enclosed by X'7C'
)
[root@xifenfei dul]# more CHF_SALES_P2_SUB2.ctl
load data
CHARACTERSET ZHS16GBK
infile 'CHF_SALES_P2_SUB2.dat'
insert
into table "CHF"."SALES"
fields terminated by whitespace
(
  "PRODUCT_ID"                       CHAR(5) enclosed by X'7C'
 ,"SALES_DATE"                       DATE "DD-MON-YYYY AD HH24:MI:SS" enclosed by X'7C'
 ,"SALES_COST"                       CHAR(3) enclosed by X'7C'
 ,"STATUS"                           CHAR(8) enclosed by X'7C'
)

这里证明所有的控制文件中的表结构都是整个表的结构，而不是分区表，在实际处理过程中，可以考虑交换分区来实现

完美解决dul处理clob字段乱码问题

使用过dul的人都知道，dul在处理clob字段的时候，经常性出现乱码，而且官方没有提供好的处理方法，通过不断的测试折腾终于在2013年春节解决了2012年困惑在我心中的疑惑，不再因为dul不可以处理clob而觉得odu/aul更加高级。这个算是2013年给自己的第一份ORACLE数据库恢复方面大礼包.
在dul中，虽然提供了LDR_OUTPUT_IN_UTF8选项，让所有的clob变为UTF8，但是在实际测试中，没有成功.这里对于clob字段处理结果对比：
配置init.dul参数

osd_big_endian_flag=false
osd_dba_file_bits=10
osd_c_struct_alignment=32
osd_file_leader_size=1
osd_word_size = 32
feedback = 1000
dc_columns=2000000
dc_tables=10000
dc_objects=1000000
dc_users=400
dc_segments=100000
USE_LOB_FILES =TRUE
control_file = control.dul
LDR_ENCLOSE_CHAR=|
db_block_size=8192
export_mode=FALSE
compatible=11

正常情况下测试clob字段

[oracle@xifenfei dul]$ ./dul
Data UnLoader: 10.2.0.5.20 - Internal Only - on Sat Jan 19 00:19:05 2013
with 64-bit io functions
Copyright (c) 1994 2013 Bernard van Duijnen All rights reserved.
 Strictly Oracle Internal Use Only
DUL> unload table chf.EVT_T_COMMON_LOG;
. unloading (index organized) table     LOB024001aa
DUL: Warning: Recreating file "LOB024001aa.ctl"
       0 rows unloaded
. unloading (index organized) table     LOB024001da
DUL: Warning: Recreating file "LOB024001da.ctl"
       0 rows unloaded
. unloading (index organized) table     LOB0240020a
DUL: Warning: Recreating file "LOB0240020a.ctl"
       0 rows unloaded
. unloading (index organized) table     LOB0240023a
DUL: Warning: Recreating file "LOB0240023a.ctl"
       0 rows unloaded
. unloading (index organized) table     LOB0240026a
DUL: Warning: Recreating file "LOB0240026a.ctl"
       0 rows unloaded
Preparing lob metadata from lob index
Reading LOB024001aa.dat 0 entries loaded and sorted 0 entries
Preparing lob metadata from lob index
Reading LOB024001da.dat 0 entries loaded and sorted 0 entries
Preparing lob metadata from lob index
Reading LOB0240020a.dat 0 entries loaded and sorted 0 entries
Preparing lob metadata from lob index
Reading LOB0240023a.dat 0 entries loaded and sorted 0 entries
Preparing lob metadata from lob index
Reading LOB0240026a.dat 0 entries loaded and sorted 0 entries
. unloading table          EVT_T_COMMON_LOG
DUL: Warning: Recreating file "CHF_EVT_T_COMMON_LOG.ctl"
    1863 rows unloaded
--修改CHF_EVT_T_COMMON_LOG.ctl中的导入表名为TEST.T_TEST
--创建测试表
SQL> create table t_test as
  2   select * from chf.EVT_T_COMMON_LOG where 1=0;
Table created.
--导入数据
[oracle@xifenfei dul]$ sqlldr test/test control=CHF_EVT_T_COMMON_LOG.ctl
SQL*Loader: Release 11.2.0.3.0 - Production on Fri Jan 18 23:50:32 2013
Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved.
Commit point reached - logical record count 64
Commit point reached - logical record count 128
…………
Commit point reached - logical record count 1856
Commit point reached - logical record count 1863
--测试数据是否乱码
SQL> desc chf.EVT_T_COMMON_LOG
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------
 ID                                        NOT NULL VARCHAR2(64)
 CASES_OF_STATISTICAL_SITATION                      CLOB
…………
 DEPARTMENT_ID                                      VARCHAR2(40)
 MOTIFY_MAN_ID                                      VARCHAR2(40)
SQL>  select CASES_OF_STATISTICAL_SITATION from t_test where rownum<3;
CASES_OF_STATISTICAL_SITATION
--------------------------------------------------------------------------------
b*kb
     _SfZz

通过试验证明，在dul处理clob字段的时候，很容易出现乱码，因为这里涉及到很多中情况(NLS_LANG,LANG,LDR_OUTPUT_IN_UTF8参数等)，经过了多次试验，均不能成功，这里就是为了给出来一个大概的结论：dul在正常情况下不能完美的处理非英文的clob

修改后lob字段文件属性后测试clob字段

--修改CHF_EVT_T_COMMON_LOG.ctl中的导入表名为TEST.EVT_T_COMMON_LOG
--导入数据
[oracle@xifenfei dul]$ sqlldr test/test control=CHF_EVT_T_COMMON_LOG.ctl
SQL*Loader: Release 11.2.0.3.0 - Production on Fri Jan 18 23:50:32 2013
Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved.
Commit point reached - logical record count 64
Commit point reached - logical record count 128
…………
Commit point reached - logical record count 1856
Commit point reached - logical record count 1863
--测试数据是否乱码
SQL> select CASES_OF_STATISTICAL_SITATION from EVT_T_COMMON_LOG where rownum<3;
CASES_OF_STATISTICAL_SITATION
--------------------------------------------------------------------------------
1、案件统计情况截止至交班时间Ｃ时间 0 分），今日立难点问题Ｃ7，国庆北路桂门岭社区丽都花园路口，多次上

测试证明:修改了clob文件的相关属性后，完美实现dul处理clob乱码问题

dul恢复drop表测试

dul对被drop对象进行恢复，需要提供两个信息
1.被删除表所属表空间(非必须)
2.被删除表结构(必须)
模拟删除表

--创建测试表
SQL> create table t_dul_drop tablespace czum
  2  as
  3  select * from dba_tables;
Table created.
--备份被删除表数据，便于比较和提供测试表结构
SQL> create table t_dul_drop_bak tablespace users
  2  as select * from t_dul_drop;
Table created.
SQL> alter system switch logfile;
System altered.
SQL> select count(*) from t_dul_drop;
  COUNT(*)
----------
      1785
SQL> drop table chf.t_dul_drop purge;
Table dropped.
SQL> alter system checkpoint;
System altered.

使用logminer找到data_object_id

delete from "SYS"."OBJ$" where "OBJ#" = '68474' and "DATAOBJ#" = '68474'
and "OWNER#" = '61' and "NAME" = 'T_DUL_DROP' and "NAMESPACE" = '1' and
"SUBNAME" IS NULL and "TYPE#" = '2' and "CTIME" = TO_DATE('04-FEB-13', 'DD-MON-RR')
and "MTIME" = TO_DATE('04-FEB-13', 'DD-MON-RR') and "STIME" = TO_DATE('04-FEB-13', 'DD-MON-RR')
and "STATUS" = '1' and "REMOTEOWNER" IS NULL and "LINKNAME" IS NULL and "FLAGS" = '0'
and "OID$" IS NULL and "SPARE1" = '6' and "SPARE2" = '1' and "SPARE3" = '61' and
"SPARE4" IS NULL and "SPARE5" IS NULL and "SPARE6" IS NULL and ROWID = 'AAAAASAABAAAPzCAAV';

这里可以知道，被删除表的data_object_id为68474

DUL恢复被删除表

--dul版本
E:\dul10>dul.exe
Data UnLoader 10.2.4.37 - Oracle Internal Only - on Mon Feb 04 23:49:50 2013
with 64-bit io functions
Copyright (c) 1994 2010 Bernard van Duijnen All rights reserved.
 Strictly Oracle Internal use Only
DUL>  ALTER SESSION SET USE_SCANNED_EXTENT_MAP = TRUE;
Parameter altered
--扫描所属表空间
DUL> scan tablespace 6;
Scanning tablespace 6, data file 6 ...
  13 segment header and 331 data blocks
  tablespace 6, data file 6: 1279 blocks scanned
Reading EXT.dat 13 entries loaded and sorted 13 entries
Reading SEG.dat 13 entries loaded
Reading COMPATSEG.dat 0 entries loaded
Reading SCANNEDLOBPAGE.dat 0 entries loaded and sorted 0 entries
--scan tables得到需求表(可以核对数据样例)
DUL> scan tables;
UNLOAD TABLE OBJNO68474 ( COL001 VARCHAR2(11), COL002 VARCHAR2(30), COL003 VARCHAR2(6)
        , COL004 VARCHAR2(20), COL005 VARCHAR2(30), COL006 VARCHAR2(5), COL007 NUMBER
        , COL008 NUMBER, COL009 NUMBER, COL010 NUMBER, COL011 NUMBER
        , COL012 NUMBER, COL013 NUMBER, COL014 NUMBER, COL015 CHAR
        , COL016 NUMBER, COL017 NUMBER, COL018 VARCHAR2(3), COL019 VARCHAR2(1)
        , COL020 NUMBER, COL021 NUMBER, COL022 NUMBER, COL023 NUMBER
        , COL024 NUMBER, COL025 NUMBER, COL026 NUMBER, COL027 NUMBER
        , COL028 VARCHAR2(10), COL029 VARCHAR2(10), COL030 VARCHAR2(5), COL031 VARCHAR2(7)
        , COL032 NUMBER, COL033 DATE, COL034 VARCHAR2(3), COL035 VARCHAR2(12)
        , COL036 VARCHAR2(1), COL037 VARCHAR2(1), COL038 VARCHAR2(3), COL039 VARCHAR2(7)
        , COL040 VARCHAR2(7), COL041 VARCHAR2(7), COL042 VARCHAR2(8), COL043 VARCHAR2(3)
        , COL044 VARCHAR2(2), COL045 VARCHAR2(15), COL046 VARCHAR2(8), COL047 VARCHAR2(3)
        , COL048 VARCHAR2(3), COL049 VARCHAR2(8), COL050 VARCHAR2(8), COL051 VARCHAR2(5)
        , COL052 VARCHAR2(2), COL053 VARCHAR2(2), COL054 VARCHAR2(3), COL055 VARCHAR2(7) )
    STORAGE( DATAOBJNO 68474 );
--恢复删除表(业务提供表结构)
DUL> unload table t_dul_drop(
  2  OWNER                              VARCHAR2(30),
  3  TABLE_NAME                         VARCHAR2(30),
  4  TABLESPACE_NAME                                    VARCHAR2(30),
  5  CLUSTER_NAME                                       VARCHAR2(30),
  6  IOT_NAME                                           VARCHAR2(30),
  7  STATUS                                             VARCHAR2(8) ,
  8  PCT_FREE                                           NUMBER      ,
  9  PCT_USED                                           NUMBER      ,
 10  INI_TRANS                                          NUMBER      ,
 11  MAX_TRANS                                          NUMBER      ,
 12  INITIAL_EXTENT                                     NUMBER      ,
 13  NEXT_EXTENT                                        NUMBER      ,
 14  MIN_EXTENTS                                        NUMBER      ,
 15  MAX_EXTENTS                                        NUMBER      ,
 16  PCT_INCREASE                                       NUMBER      ,
 17  FREELISTS                                          NUMBER      ,
 18  FREELIST_GROUPS                                    NUMBER      ,
 19  LOGGING                                            VARCHAR2(3) ,
 20  BACKED_UP                                          VARCHAR2(1) ,
 21  NUM_ROWS                                           NUMBER      ,
 22  BLOCKS                                             NUMBER      ,
 23  EMPTY_BLOCKS                                       NUMBER      ,
 24  AVG_SPACE                                          NUMBER      ,
 25  CHAIN_CNT                                          NUMBER      ,
 26  AVG_ROW_LEN                                        NUMBER      ,
 27  AVG_SPACE_FREELIST_BLOCKS                          NUMBER      ,
 28  NUM_FREELIST_BLOCKS                                NUMBER      ,
 29  DEGREE                                             VARCHAR2(20),
 30  INSTANCES                                          VARCHAR2(20),
 31  CACHE                                              VARCHAR2(10),
 32  TABLE_LOCK                                         VARCHAR2(8) ,
 33  SAMPLE_SIZE                                        NUMBER      ,
 34  LAST_ANALYZED                                      DATE        ,
 35  PARTITIONED                                        VARCHAR2(3) ,
 36  IOT_TYPE                                           VARCHAR2(12),
 37  TEMPORARY                                          VARCHAR2(1) ,
 38  SECONDARY                                          VARCHAR2(1) ,
 39  NESTED                                             VARCHAR2(3) ,
 40  BUFFER_POOL                                        VARCHAR2(7) ,
 41  FLASH_CACHE                                        VARCHAR2(7) ,
 42  CELL_FLASH_CACHE                                   VARCHAR2(7) ,
 43  ROW_MOVEMENT                                       VARCHAR2(8) ,
 44  GLOBAL_STATS                                       VARCHAR2(3) ,
 45  USER_STATS                                         VARCHAR2(3) ,
 46  DURATION                                           VARCHAR2(15),
 47  SKIP_CORRUPT                                       VARCHAR2(8) ,
 48  MONITORING                                         VARCHAR2(3) ,
 49  CLUSTER_OWNER                                      VARCHAR2(30),
 50  DEPENDENCIES                                       VARCHAR2(8) ,
 51  COMPRESSION                                        VARCHAR2(8) ,
 52  COMPRESS_FOR                                       VARCHAR2(12),
 53  DROPPED                                            VARCHAR2(3) ,
 54  READ_ONLY                                          VARCHAR2(3) ,
 55  SEGMENT_CREATED                                    VARCHAR2(3) ,
 56  RESULT_CACHE                                       VARCHAR2(7))
 57   STORAGE( DATAOBJNO 68474 );
. unloading table                T_DUL_DROP
DUL: Warning: Recreating file "T_DUL_DROP.ctl"
    1785 rows unloaded

模拟业务规则提供，创建表

SQL> create table t_dul_drop as select * from t_dul_drop_bak where 1=0;
Table created.

导入数据

e:\dul10>sqlldr chf/xifenfei control=T_DUL_DROP.ctl
SQL*Loader: Release 11.2.0.3.0 - Production on Mon Feb 4 23:35:57 2013
Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved.
Commit point reached - logical record count 64
Commit point reached - logical record count 128
Commit point reached - logical record count 192
Commit point reached - logical record count 256
Commit point reached - logical record count 320
Commit point reached - logical record count 384
Commit point reached - logical record count 448
Commit point reached - logical record count 512
Commit point reached - logical record count 576
Commit point reached - logical record count 640
Commit point reached - logical record count 704
Commit point reached - logical record count 768
Commit point reached - logical record count 832
Commit point reached - logical record count 896
Commit point reached - logical record count 960
Commit point reached - logical record count 1024
Commit point reached - logical record count 1088
Commit point reached - logical record count 1152
Commit point reached - logical record count 1216
Commit point reached - logical record count 1280
Commit point reached - logical record count 1344
Commit point reached - logical record count 1408
Commit point reached - logical record count 1472
Commit point reached - logical record count 1536
Commit point reached - logical record count 1600
Commit point reached - logical record count 1664
Commit point reached - logical record count 1728
Commit point reached - logical record count 1785

恢复数据结果

SQL> select count(*) from t_dul_drop;
  COUNT(*)
----------
      1785
SQL> select owner,table_name from t_dul_drop where rownum<10;
OWNER                          TABLE_NAME
------------------------------ ------------------------------
SYS                            IDL_CHAR$
SYS                            IDL_UB2$
SYS                            IDL_SB4$
SYS                            ERROR$
SYS                            SETTINGS$
SYS                            NCOMP_DLL$
SYS                            PROCEDUREJAVA$
SYS                            PROCEDUREC$
SYS                            PROCEDUREPLSQL$
9 rows selected.

dul恢复truncate表测试

dul 恢复truncate 测试
准备dul测试

SQL> select count(*) from t_xifenfei;
  COUNT(*)
----------
     67854
SQL> desc t_xifenfei
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------
 OWNER                                              VARCHAR2(30)
 OBJECT_NAME                                        VARCHAR2(128)
 SUBOBJECT_NAME                                     VARCHAR2(30)
 OBJECT_ID                                          NUMBER
 DATA_OBJECT_ID                                     NUMBER
 OBJECT_TYPE                                        VARCHAR2(19)
 CREATED                                            DATE
 LAST_DDL_TIME                                      DATE
 TIMESTAMP                                          VARCHAR2(19)
 STATUS                                             VARCHAR2(7)
 TEMPORARY                                          VARCHAR2(1)
 GENERATED                                          VARCHAR2(1)
 SECONDARY                                          VARCHAR2(1)
 NAMESPACE                                          NUMBER
 EDITION_NAME                                       VARCHAR2(30)
SQL> select object_id,data_object_id from user_objects where object_name='T_XIFENFEI';
 OBJECT_ID DATA_OBJECT_ID
---------- --------------
     68332          68332
SQL> TRUNCATE TABLE T_XIFENFEI;
Table truncated.
SQL> ALTER SYSTEM CHECKPOINT;
System altered.
SQL> select object_id,data_object_id from user_objects where object_name='T_XIFE
NFEI';
 OBJECT_ID DATA_OBJECT_ID
---------- --------------
     68332          68468
SQL> SELECT TABLESPACE_NAME FROM DBA_SEGMENTS WHERE SEGMENT_NAME='T_XIFENFEI';
TABLESPACE_NAME
------------------------------
USERS
SQL> SELECT FILE_ID FROM DBA_DATA_FILES WHERE TABLESPACE_NAME='USERS';
   FILE_ID
----------
         4
SQL> SELECT file#,RFILE#,NAME FROM V$DATAFILE;
     FILE#     RFILE# NAME
---------- ---------- --------------------------------------------------
         1          1 E:\ORACLE\ORADATA\XIFENFEI\SYSTEM01.DBF
         2          2 E:\ORACLE\ORADATA\XIFENFEI\SYSAUX01.DBF
         3          3 E:\ORACLE\ORADATA\XIFENFEI\UNDOTBS01.DBF
         4          4 E:\ORACLE\ORADATA\XIFENFEI\USERS01.DBF
         5          5 E:\ORACLE\ORADATA\XIFENFEI\UNDO01.DBF
         6          6 E:\ORACLE\ORADATA\XIFENFEI\CZUM01.DBF
6 rows selected.

备注说明：因为我们为了测试，所以直接查询出来了data_object_id，在实际的恢复中，我们需要使用logminer来找出来历史dataobj#

dul恢复truncate 表

e:\dul10>dul.exe
Data UnLoader 10.2.4.37 - Oracle Internal Only - on Mon Feb 04 00:20:08 2013
with 64-bit io functions
Copyright (c) 1994 2010 Bernard van Duijnen All rights reserved.
 Strictly Oracle Internal use Only
DUL: Warning: Recreating file "dul.log"
Reading USER.dat 65 entries loaded
Reading OBJ.dat 67944 entries loaded and sorted 67944 entries
Reading SCANNEDLOBPAGE.dat 8 entries loaded and sorted 8 entries
Reading TAB.dat 1869 entries loaded
Reading COL.dat 77409 entries loaded and sorted 77409 entries
Reading SEG.dat 23 entries loaded
Reading EXT.dat 54 entries loaded and sorted 54 entries
Reading TABPART.dat 110 entries loaded and sorted 110 entries
Reading TABCOMPART.dat 1 entries loaded and sorted 1 entries
Reading TABSUBPART.dat 32 entries loaded and sorted 32 entries
Reading INDPART.dat 127 entries loaded and sorted 127 entries
Reading INDCOMPART.dat 0 entries loaded and sorted 0 entries
Reading INDSUBPART.dat 0 entries loaded and sorted 0 entries
Reading IND.dat 3729 entries loaded
Reading LOB.dat
DUL: Warning: Increased the size of DC_LOBS from 1024 to 8192 entries
 1109 entries loaded
Reading ICOL.dat 4868 entries loaded
Reading COLTYPE.dat 2823 entries loaded
Reading TYPE.dat 2082 entries loaded
Reading ATTRIBUTE.dat 8736 entries loaded
Reading COLLECTION.dat 591 entries loaded
Reading COMPATSEG.dat 0 entries loaded
Reading BOOTSTRAP.dat 60 entries loaded
Reading LOBFRAG.dat 1 entries loaded and sorted 1 entries
Reading LOBCOMPPART.dat 0 entries loaded and sorted 0 entries
Reading UNDO.dat 24 entries loaded
Reading TS.dat 7 entries loaded
Reading PROPS.dat 36 entries loaded
Database character set is ZHS16GBK
Database national character set is AL16UTF16
Found db_id = 1422012639
Found db_name = XIFENFEI
DUL> SCAN DATAFILE 4;
DUL: Warning: Recreating file "EXT.dat"
DUL: Warning: Recreating file "SEG.dat"
DUL: Warning: Recreating file "COMPATSEG.dat"
DUL: Warning: Recreating file "SCANNEDLOBPAGE.dat"
Scanning tablespace 4, data file 4 ...
  23 segment header and 1601 data blocks
  tablespace 4, data file 4: 2079 blocks scanned
Reading EXT.dat 54 entries loaded and sorted 54 entries
Reading SEG.dat 23 entries loaded
Reading COMPATSEG.dat 0 entries loaded
Reading SCANNEDLOBPAGE.dat 8 entries loaded and sorted 8 entries
DUL>  ALTER SESSION SET USE_SCANNED_EXTENT_MAP = TRUE;
Parameter altered
DUL> scan extents;
DUL: Warning: Recreating file "seen_tab.dat"
DUL: Warning: Recreating file "seen_col.dat"
Scanning extents without segment header
Scanning extent id (dba 0, obj 68332)
Analyzing segment: data object id 68332
  heap organized table
Col    Seen  Max PCT  PRINT  NUMBERS DATES TIMESTAMP WITH TZ INTRVAL  ROWIDS LOB
 no   count Size NUL 75%100% AnyNice AnyNice AnyNice AnyNice Y2M D2S AnyNice
  1   67854   18   0 100 100   0   0   0   0   0   0   0   0   0   0  44   0   0
…………
 14   67854    2   0   0   0 100 100   0   0   0   0   0   0   0   0   0   0   0
|SYS| |C_FILE#_BLOCK#| || |8| |8| |CLUSTER| |20-JAN-2013 AD 17:13:18| |20-JAN-20
…………
:18| |2013-01-20:17:13:18| |VALID| |N| |N| |N| |1|
UNLOAD TABLE OBJNO68332 ( COL001 VARCHAR2(18), COL002 VARCHAR2(30), COL003 VARCH
AR2(27)
        , COL004 NUMBER, COL005 NUMBER, COL006 VARCHAR2(18), COL007 DATE
        , COL008 DATE, COL009 VARCHAR2(19), COL010 VARCHAR2(7), COL011 VARCHAR2(
1)
        , COL012 VARCHAR2(1), COL013 VARCHAR2(1), COL014 NUMBER )
    STORAGE( DATAOBJNO 68332 );
--自己拼接语句
DUL> UNLOAD TABLE t_xifenfei_1(OWNER VARCHAR2(30),OBJECT_NAME  VARCHAR2(128),SUB
OBJECT_NAME    VARCHAR2(30),OBJECT_ID  NUMBER,DATA_OBJECT_ID    NUMBER,OBJECT_TY
PE  VARCHAR2(19),CREATED    DATE,LAST_DDL_TIME DATE,TIMESTAMP    VARCHAR2(19),ST
ATUS VARCHAR2(7),TEMPORARY    VARCHAR2(1),GENERATED    VARCHAR2(1),SECONDARY
VARCHAR2(1),NAMESPACE    NUMBER,EDITION_NAME VARCHAR2(30))  STORAGE( DATAOBJNO 6
8332 );
. unloading table              T_XIFENFEI_1
DUL: Warning: Recreating file "T_XIFENFEI_1.ctl"
   67854 rows unloaded

补充说明：
1.在最新的dul 10.2.0.5.20中，不支持scan extents命令
2.在最新的dul 10.2.0.5.20中，挖出来的无数据字典数据，字符串转换为16进制值

table中各种类型block坏块是否能被跳过

在table遇到的各种坏块中，大部分情况，我们都可以通过设置event 10231或者dbms_repair来跳过坏块，抢救其他数据；但是在部分情况下，我们设置了他们依然不能跳过坏块，数据库依然报ORA-01578,本文测试了table中各种类型的block，证明在哪些blog出现异常之后不能被跳过.
如果是事务数据块出现坏块可以通过dbms_repair.skip_corrupt_blocks来标记坏块(也可以使用event 10231)来实现；对于BITMAP BLOCK如果出现坏块不会对于读取数据无影响(至于其他操作,请见后续blog)；SEGMENT HEADER如果出现坏块，无法通过跳过坏块来实现获取其他数据(正常block)
创建测试表

SQL> select * from v$version;
BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - Production
PL/SQL Release 11.2.0.3.0 - Production
CORE    11.2.0.3.0      Production
TNS for Linux: Version 11.2.0.3.0 - Production
NLSRTL Version 11.2.0.3.0 - Production
SQL> create table t_xifenfei
  2  tablespace users
  3  as
  4  select * from dba_objects;
Table created.
SQL>  select count(*) from chf.t_xifenfei;
  COUNT(*)
----------
     74663

查询相关block信息

SQL> select SEGMENT_NAME,HEADER_FILE,HEADER_BLOCK,blocks,extents from DBA_SEGMENTS
  2  WHERE OWNER='CHF' AND SEGMENT_NAME='T_XIFENFEI';
SEGMENT_NAME    HEADER_FILE HEADER_BLOCK     BLOCKS    EXTENTS
--------------- ----------- ------------ ---------- ----------
T_XIFENFEI                4          378       1152         24
SQL>   select
  2    dbms_rowid.rowid_relative_fno(rowid)rel_fno,
  3    max(dbms_rowid.rowid_block_number(rowid)) max_block,
  4    min(dbms_rowid.rowid_block_number(rowid)) min_block
  5    from chf.t_xifenfei
  6    group by dbms_rowid.rowid_relative_fno(rowid);
   REL_FNO  MAX_BLOCK  MIN_BLOCK
---------- ---------- ----------
         4       1728        379
SQL> select EXTENT_ID,FILE_ID,BLOCK_ID,blocks from dba_extents where owner='CHF'
   2  AND SEGMENT_NAME='T_XIFENFEI';
 EXTENT_ID    FILE_ID   BLOCK_ID     BLOCKS
---------- ---------- ---------- ----------
         0          4        376          8
         1          4        640          8
         2          4        648          8
         3          4        656          8
         4          4        664          8
         5          4        672          8
         6          4        680          8
         7          4        688          8
         8          4        696          8
         9          4        704          8
        10          4        712          8
        11          4        720          8
        12          4        728          8
        13          4        736          8
        14          4        744          8
        15          4        752          8
        16          4        768        128
        17          4        896        128
        18          4       1024        128
        19          4       1152        128
        20          4       1280        128
        21          4       1408        128
        22          4       1536        128
        23          4       1664        128

通过这里可以知道:真正的存储数据是从block 379开始,至于block 376、377、378是什么，使用dump block分析

验证block类型

SQL> alter system dump datafile 4 block 376;
System altered.
SQL> alter system dump datafile 4 block 377;
System altered.
SQL> alter system dump datafile 4 block 378;
System altered.
SQL> alter system dump datafile 4 block 379;
System altered.
--该block是另外extent的开始，所以也尝试分析是否有特殊之处
SQL> alter system dump datafile 4 block 640;
System altered.
--dump 文件header信息
Start dump data blocks tsn: 4 file#:4 minblk 376 maxblk 376
Block dump from cache:
Dump of buffer cache at level 4 for tsn=4 rdba=16777592
Block dump from disk:
buffer tsn: 4 rdba: 0x01000178 (4/376)
scn: 0x0b8c.3bfc6517 seq: 0x04 flg: 0x04 tail: 0x65172004
frmt: 0x02 chkval: 0xc8b3 type: 0x20=FIRST LEVEL BITMAP BLOCK
Start dump data blocks tsn: 4 file#:4 minblk 377 maxblk 377
Block dump from cache:
Dump of buffer cache at level 4 for tsn=4 rdba=16777593
Block dump from disk:
buffer tsn: 4 rdba: 0x01000179 (4/377)
scn: 0x0b8c.3bfc6517 seq: 0x18 flg: 0x04 tail: 0x65172118
frmt: 0x02 chkval: 0x9e8c type: 0x21=SECOND LEVEL BITMAP BLOCK
Start dump data blocks tsn: 4 file#:4 minblk 378 maxblk 378
Block dump from cache:
Dump of buffer cache at level 4 for tsn=4 rdba=16777594
BH (0x2a7f7f0c) file#: 4 rdba: 0x0100017a (4/378) class: 4 ba: 0x2a742000
  set: 5 pool: 3 bsz: 8192 bsi: 0 sflg: 1 pwc: 0,0
  dbwrid: 0 obj: 76372 objn: 76372 tsn: 4 afn: 4 hint: f
  hash: [0x3150a748,0x3150a748] lru: [0x2a7f8094,0x2a7f7ee4]
  lru-flags: hot_buffer
  ckptq: [NULL] fileq: [NULL] objq: [0x2f72dc34,0x2f72dc34] objaq: [0x2f72dc2c,0x2f72dc2c]
  st: XCURRENT md: NULL fpin: 'ktewh25: kteinicnt' tch: 1
  flags:
  LRBA: [0x0.0.0] LSCN: [0x0.0] HSCN: [0xffff.ffffffff] HSUB: [65535]
Block dump from disk:
buffer tsn: 4 rdba: 0x0100017a (4/378)
scn: 0x0b8c.3bfc651b seq: 0x01 flg: 0x04 tail: 0x651b2301
frmt: 0x02 chkval: 0xb2ae type: 0x23=PAGETABLE SEGMENT HEADER
Start dump data blocks tsn: 4 file#:4 minblk 379 maxblk 379
Block dump from cache:
Dump of buffer cache at level 4 for tsn=4 rdba=16777595
Block dump from disk:
buffer tsn: 4 rdba: 0x0100017b (4/379)
scn: 0x0b8c.3bfc6494 seq: 0x01 flg: 0x04 tail: 0x64940601
frmt: 0x02 chkval: 0x0567 type: 0x06=trans data
Start dump data blocks tsn: 4 file#:4 minblk 640 maxblk 640
Block dump from cache:
Dump of buffer cache at level 4 for tsn=4 rdba=16777856
Block dump from disk:
buffer tsn: 4 rdba: 0x01000280 (4/640)
scn: 0x0b8c.3bfc6496 seq: 0x01 flg: 0x04 tail: 0x64960601
frmt: 0x02 chkval: 0x0efe type: 0x06=trans data

这里可以知道：
1.block 376、377为BITMAP BLOCK
2.block 378为SEGMENT HEADER(和dba_segments视图中一致)
3.除extent 0中有特殊(含BITMAP BLOCK和SEGMENT HEADER)block，其他extent只包含事务数据

测试block 640

--block 640包含条数
SQL> select   count(rowid)
  2    from chf.t_xifenfei
  3     where dbms_rowid.rowid_block_number(rowid)=640
  4  and dbms_rowid.rowid_relative_fno(rowid)=4;
COUNT(ROWID)
------------
          79
--bbed修改tailchk
BBED> set filename '/u01/oracle/oradata/ora11g/users01.dbf'
        FILENAME        /u01/oracle/oradata/ora11g/users01.dbf
BBED> set block 640
        BLOCK#          640
BBED> set mode edit
        MODE            Edit
BBED> p tailchk
ub4 tailchk                                 @8188     0x64960601
BBED> m /x 64960602
Warning: contents of previous BIFILE will be lost. Proceed? (Y/N) y
 File: /u01/oracle/oradata/ora11g/users01.dbf (0)
 Block: 640              Offsets: 8188 to 8191           Dba:0x00000000
------------------------------------------------------------------------
 64960602
 <32 bytes per line>
BBED> sum apply
Check value for File 0, Block 640:
current = 0xf80b, required = 0xf80b
BBED> verify
DBVERIFY - Verification starting
FILE = /u01/oracle/oradata/ora11g/users01.dbf
BLOCK = 640
Block 640 is corrupt
Corrupt block relative dba: 0x01000280 (file 0, block 640)
Fractured block found during verification
Data in bad block:
 type: 6 format: 2 rdba: 0x01000280
 last change scn: 0x0b8c.3bfc6496 seq: 0x1 flg: 0x04
 spare1: 0x0 spare2: 0x0 spare3: 0x0
 consistency value in tail: 0x02069664
 check value in block header: 0xf80b
 computed block checksum: 0x0
DBVERIFY - Verification complete
Total Blocks Examined         : 1
Total Blocks Processed (Data) : 0
Total Blocks Failing   (Data) : 0
Total Blocks Processed (Index): 0
Total Blocks Failing   (Index): 0
Total Blocks Empty            : 0
Total Blocks Marked Corrupt   : 1
Total Blocks Influx           : 2
Message 531 not found;  product=RDBMS; facility=BBED
--查询坏块
SQL> select count(*) from chf.t_xifenfei;
select count(*) from chf.t_xifenfei
                         *
ERROR at line 1:
ORA-01578: ORACLE data block corrupted (file # 4, block # 640)
ORA-01110: data file 4: '/u01/oracle/oradata/ora11g/users01.dbf'
--跳过坏块
SQL> exec dbms_repair.skip_corrupt_blocks('CHF','T_XIFENFEI');
PL/SQL procedure successfully completed.
SQL>  select skip_corrupt from dba_tables where table_name='T_XIFENFEI' AND OWNER='CHF';
SKIP_COR
--------
ENABLED
SQL>  select count(*) from chf.t_xifenfei;
  COUNT(*)
----------
     74584
--修复坏块
BBED> m /x 01069664
Warning: contents of previous BIFILE will be lost. Proceed? (Y/N) y
 File: /u01/oracle/oradata/ora11g/users01.dbf (0)
 Block: 640              Offsets: 8188 to 8191           Dba:0x00000000
------------------------------------------------------------------------
 01069664
 <32 bytes per line>
BBED> p tailchk
ub4 tailchk                                 @8188     0x64960601
BBED> sum apply
Check value for File 0, Block 640:
current = 0x0efe, required = 0x0efe
BBED> verify
DBVERIFY - Verification starting
FILE = /u01/oracle/oradata/ora11g/users01.dbf
BLOCK = 640
DBVERIFY - Verification complete
Total Blocks Examined         : 1
Total Blocks Processed (Data) : 1
Total Blocks Failing   (Data) : 0
Total Blocks Processed (Index): 0
Total Blocks Failing   (Index): 0
Total Blocks Empty            : 0
Total Blocks Marked Corrupt   : 0
Total Blocks Influx           : 0
Message 531 not found;  product=RDBMS; facility=BBED
--除掉标记表坏块
SQL> BEGIN
  2  DBMS_REPAIR.SKIP_CORRUPT_BLOCKS (
  3  SCHEMA_NAME => 'CHF',
  4  OBJECT_NAME => 'T_XIFENFEI',
  5  OBJECT_TYPE => dbms_repair.table_object,
  6  FLAGS => dbms_repair.NOSKIP_FLAG);
  7  END;
  8  /
PL/SQL procedure successfully completed.
SQL> select skip_corrupt from dba_tables where table_name='T_XIFENFEI' AND OWNER='CHF';
SKIP_COR
--------
DISABLED
--查询表记录正常
SQL>  select count(*) from chf.t_xifenfei;
  COUNT(*)
----------
     74663

在后续的操作中，也是按照类似步骤操作，考虑到篇幅有限，部分过程不再贴出来

测试block 379

SQL>  select count(*) from chf.t_xifenfei;
 select count(*) from chf.t_xifenfei
                          *
ERROR at line 1:
ORA-01578: ORACLE data block corrupted (file # 4, block # 379)
ORA-01110: data file 4: '/u01/oracle/oradata/ora11g/users01.dbf'
SQL> exec dbms_repair.skip_corrupt_blocks('CHF','T_XIFENFEI');
PL/SQL procedure successfully completed.
SQL> select count(*) from chf.t_xifenfei;
  COUNT(*)
----------
     74575

测试block 378

BBED> set block 378
        BLOCK#          378
--segment header 不支持bbed查看结构
BBED> p tailchk
BBED-00400: invalid blocktype (35)
BBED> map
 File: /u01/oracle/oradata/ora11g/users01.dbf (0)
 Block: 378                                   Dba:0x00000000
------------------------------------------------------------
BBED-00400: invalid blocktype (35)
BBED> set offset 8188
        OFFSET          8188
BBED> d
 File: /u01/oracle/oradata/ora11g/users01.dbf (0)
 Block: 378              Offsets: 8188 to 8191           Dba:0x00000000
------------------------------------------------------------------------
 01231b65
 <32 bytes per line>
BBED> m /x 651b2302
Warning: contents of previous BIFILE will be lost. Proceed? (Y/N) y
 File: /u01/oracle/oradata/ora11g/users01.dbf (0)
 Block: 378              Offsets: 8188 to 8191           Dba:0x00000000
------------------------------------------------------------------------
 651b2302
 <32 bytes per line>
BBED> sum apply
Check value for File 0, Block 378:
current = 0xedf2, required = 0xedf2
--验证坏块
BBED> verify
DBVERIFY - Verification starting
FILE = /u01/oracle/oradata/ora11g/users01.dbf
BLOCK = 378
Block 378 is corrupt
Corrupt block relative dba: 0x0100017a (file 0, block 378)
Fractured block found during verification
Data in bad block:
 type: 35 format: 2 rdba: 0x0100017a
 last change scn: 0x0b8c.3bfc651b seq: 0x1 flg: 0x04
 spare1: 0x0 spare2: 0x0 spare3: 0x0
 consistency value in tail: 0x02231b65
 check value in block header: 0xedf2
 computed block checksum: 0x0
DBVERIFY - Verification complete
Total Blocks Examined         : 1
Total Blocks Processed (Data) : 0
Total Blocks Failing   (Data) : 0
Total Blocks Processed (Index): 0
Total Blocks Failing   (Index): 0
Total Blocks Empty            : 0
Total Blocks Marked Corrupt   : 1
Total Blocks Influx           : 2
Message 531 not found;  product=RDBMS; facility=BBED
SQL>  select count(*) from chf.t_xifenfei;
 select count(*) from chf.t_xifenfei
                          *
ERROR at line 1:
ORA-01578: ORACLE data block corrupted (file # 4, block # 378)
ORA-01110: data file 4: '/u01/oracle/oradata/ora11g/users01.dbf'
--标记跳过坏块
SQL> exec dbms_repair.skip_corrupt_blocks('CHF','T_XIFENFEI');
PL/SQL procedure successfully completed.
--查询依然失败
SQL> select count(*) from chf.t_xifenfei;
select count(*) from chf.t_xifenfei
                         *
ERROR at line 1:
ORA-01578: ORACLE data block corrupted (file # 4, block # 378)
ORA-01110: data file 4: '/u01/oracle/oradata/ora11g/users01.dbf'

测试block 377

BBED> m /x 18211766
Warning: contents of previous BIFILE will be lost. Proceed? (Y/N) y
 File: /u01/oracle/oradata/ora11g/users01.dbf (0)
 Block: 377              Offsets: 8188 to 8191           Dba:0x00000000
------------------------------------------------------------------------
 18211766
 <32 bytes per line>
BBED> sum apply
Check value for File 0, Block 377:
current = 0x9d8c, required = 0x9d8c
--bbed验证为坏块
BBED> verify
DBVERIFY - Verification starting
FILE = /u01/oracle/oradata/ora11g/users01.dbf
BLOCK = 377
Block 377 is corrupt
Corrupt block relative dba: 0x01000179 (file 0, block 377)
Fractured block found during verification
Data in bad block:
 type: 33 format: 2 rdba: 0x01000179
 last change scn: 0x0b8c.3bfc6517 seq: 0x18 flg: 0x04
 spare1: 0x0 spare2: 0x0 spare3: 0x0
 consistency value in tail: 0x66172118
 check value in block header: 0x9d8c
 computed block checksum: 0x0
DBVERIFY - Verification complete
Total Blocks Examined         : 1
Total Blocks Processed (Data) : 0
Total Blocks Failing   (Data) : 0
Total Blocks Processed (Index): 0
Total Blocks Failing   (Index): 0
Total Blocks Empty            : 0
Total Blocks Marked Corrupt   : 1
Total Blocks Influx           : 2
Message 531 not found;  product=RDBMS; facility=BBED
--dbv验证为坏块
[oracle@xifenfei ~]$ dbv file=/u01/oracle/oradata/ora11g/users01.dbf
DBVERIFY: Release 11.2.0.3.0 - Production on Fri Jan 18 03:32:18 2013
Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved.
DBVERIFY - Verification starting : FILE = /u01/oracle/oradata/ora11g/users01.dbf
Page 377 is influx - most likely media corrupt
Corrupt block relative dba: 0x01000179 (file 4, block 377)
Fractured block found during dbv:
Data in bad block:
 type: 33 format: 2 rdba: 0x01000179
 last change scn: 0x0b8c.3bfc6517 seq: 0x18 flg: 0x04
 spare1: 0x0 spare2: 0x0 spare3: 0x0
 consistency value in tail: 0x66172118
 check value in block header: 0x9d8c
 computed block checksum: 0x0
DBVERIFY - Verification complete
Total Pages Examined         : 2560
Total Pages Processed (Data) : 1434
Total Pages Failing   (Data) : 0
Total Pages Processed (Index): 10
Total Pages Failing   (Index): 0
Total Pages Processed (Other): 213
Total Pages Processed (Seg)  : 0
Total Pages Failing   (Seg)  : 0
Total Pages Empty            : 902
Total Pages Marked Corrupt   : 1
Total Pages Influx           : 1
Total Pages Encrypted        : 0
Highest block SCN            : 1006486374 (2956.1006486374)
--查询表记录
SQL> select skip_corrupt from dba_tables where table_name='T_XIFENFEI' AND OWNER='CHF';
SKIP_COR
--------
DISABLED
SQL> select count(*) from chf.t_xifenfei;
  COUNT(*)
----------
     74663

测试block 376

BBED> m /x 04201766
 File: /u01/oracle/oradata/ora11g/users01.dbf (0)
 Block: 376              Offsets: 8188 to 8191           Dba:0x00000000
------------------------------------------------------------------------
 04201766
 <32 bytes per line>
BBED> sum apply
Check value for File 0, Block 376:
current = 0xcbb3, required = 0xcbb3
BBED> verify
DBVERIFY - Verification starting
FILE = /u01/oracle/oradata/ora11g/users01.dbf
BLOCK = 376
Block 376 is corrupt
Corrupt block relative dba: 0x01000178 (file 0, block 376)
Fractured block found during verification
Data in bad block:
 type: 32 format: 2 rdba: 0x01000178
 last change scn: 0x0b8c.3bfc6517 seq: 0x4 flg: 0x04
 spare1: 0x0 spare2: 0x0 spare3: 0x0
 consistency value in tail: 0x66172004
 check value in block header: 0xcbb3
 computed block checksum: 0x0
DBVERIFY - Verification complete
Total Blocks Examined         : 1
Total Blocks Processed (Data) : 0
Total Blocks Failing   (Data) : 0
Total Blocks Processed (Index): 0
Total Blocks Failing   (Index): 0
Total Blocks Empty            : 0
Total Blocks Marked Corrupt   : 1
Total Blocks Influx           : 2
Message 531 not found;  product=RDBMS; facility=BBED
SQL>  select count(*) from chf.t_xifenfei;
  COUNT(*)
----------
     74663

通过测试证明，如果是事务数据块出现坏块可以通过dbms_repair.skip_corrupt_blocks来标记坏块(也可以使用event 10231)来实现；对于BITMAP BLOCK如果出现坏块不会对于读取数据无影响(至于其他操作,请见table中各种坏块对select/dml操作影响)；SEGMENT HEADER如果出现坏块，无法通过跳过坏块来实现获取其他数据(正常block)

操作系统级别做systemstate

在有些时候，我们需要通过systemstate或者hanganalyze来收集数据库hang信息，但是当我们的数据库不能登录的时候，无法通过常规手段来使用该方法来收集信息。ORACLE的开发者也考虑到了类似情况，让我们可以通过dbx或者gdb来收集数据库信息.这里我通过在linux平台上模拟一个新会话，然后通过gdb直接对该会话进行做systemstate,然后操作该会话(证明gdb操作后正常),来实现类似系统hang住，无法登陆的时候怎么做systemstate.
模拟会话
就是假设我们hang住的系统中的数据库进程(为了后面gdb和验证对会话影响而使用,不然可以直接使用oracle 后台进程来完成该操作)

[oracle@xifenfei ~]$ sqlplus / as sysdba
SQL*Plus: Release 11.2.0.3.0 Production on Thu Jan 17 18:28:30 2013
Copyright (c) 1982, 2011, Oracle.  All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SQL>

查找数据库进程
在另外一个shell窗口找出数据库进程

[root@xifenfei trace]# ps -ef|grep LOCAL
oracle    7476  7473  0 18:28 ?        00:00:00 oracleora11g (DESCRIPTION=(LOCAL=YES)(ADDRESS=(PROTOCOL=beq)))
root      7487  7326  0 18:28 pts/2    00:00:00 grep LOCAL

gdb做systemstate

[oracle@xifenfei trace]$ gdb $ORACLE_HOME/bin/oracle 7476
GNU gdb (GDB) Red Hat Enterprise Linux (7.0.1-37.el5)
Copyright (C) 2009 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "i386-redhat-linux-gnu".
…………
Reading symbols from /u01/oracle/oracle/product/11.2.0/db_1/lib/libnque11.so...
Loaded symbols for /u01/oracle/oracle/product/11.2.0/db_1/lib/libnque11.so
0xb789c424 in __kernel_vsyscall ()
(gdb)  print ksudss(10)  <--输入print ksudss(10)
$1 = 0
(gdb) quit
A debugging session is active.
        Inferior 1 [process 7476] will be detached.
Quit anyway? (y or n) y
Detaching from program: /u01/oracle/oracle/product/11.2.0/db_1/bin/oracle, process 7476

查看trace文件

[oracle@xifenfei trace]$ ls -l *7476*.trc
-rw-r----- 1 oracle oinstall 742438 Jan 17 18:28 ora11g_ora_7476.trc
[oracle@xifenfei trace]$ more ora11g_ora_7476.trc
Trace file /u01/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_7476.trc
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
ORACLE_HOME = /u01/oracle/oracle/product/11.2.0/db_1
System name:    Linux
Node name:      xifenfei
Release:        2.6.32-200.13.1.el5uek
Version:        #1 SMP Wed Jul 27 20:21:26 EDT 2011
Machine:        i686
VM name:        VMWare Version: 6
Instance name: ora11g
Redo thread mounted by this instance: 1
Oracle process number: 21
Unix process pid: 7476, image: oracle@xifenfei (TNS V1-V3)
*** 2013-01-17 18:28:59.225
*** SESSION ID:(143.23) 2013-01-17 18:28:59.225
*** CLIENT ID:() 2013-01-17 18:28:59.225
*** SERVICE NAME:(SYS$USERS) 2013-01-17 18:28:59.225
*** MODULE NAME:(sqlplus@xifenfei (TNS V1-V3)) 2013-01-17 18:28:59.225
*** ACTION NAME:() 2013-01-17 18:28:59.225
===================================================
SYSTEM STATE (level=10)  <---systemstate levle 10
------------
System global information:
     processes: base 0x32bc5b38, size 150, cleanup 0x32bd5990
     allocation: free sessions 0x32085b84, free calls (nil)
     control alloc errors: 0 (process), 0 (session), 0 (call)
     PMON latch cleanup depth: 0
     seconds since PMON's last scan for dead processes: 693
     system statistics:

这里证明使用gdb–>print ksudss(10)对数据库做的是systemstate level 10

验证做gdb的进程

SQL> select * from dual;
D
-
X
SQL> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

证明被gdb处理过的进程还是正常(未收到额外破坏),所以我们可以确定在系统hang住，而且新会话不能正常建立连接的时候，我们可以尝试着使用ksudss(10)来对系统做systemstate然后分析