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Oracle 手工清除回滚段的几种方法

 
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转自:Blog: http://blog.csdn.net/tianlesoftware
关于回滚段的问题,之前也小整理过一个,参考:

       Current online Redo 和 Undo 损坏的处理方法

       http://blog.csdn.net/tianlesoftware/article/details/6261475



     Roger同学昨天整理了一个更加详细的说明,转帖过来。 Roger 的原文链接如下: http://www.killdb.com/?p=196





       某些情况下,我们需要手动去清除一些有问题的回滚段,如果该回滚段中包含活动事务,那么使用正常的方式将无法drop,所以此时你dropundo tablespace 也将失败。



可能就会遇到如下的错误:

SQL> drop tablespace undotbs1 includingcontents and datafiles;

drop tablespace undotbs1 including contentsand datafiles

*

ERROR at line 1:

ORA-01561: failed to remove all objects inthe tablespace specified



方法一:用隐含参数

SQL> show parameter undo

NAME                                 TYPE        VALUE

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

undo_management                      string      AUTO

undo_retention                       integer     900

undo_tablespace                      string      UNDOTBS1

SQL> create undo tablespace undotbs2datafile '/oracle/product/oradata/roger/undotbs2.dbf'

2  size 50m autoextend off;

Tablespace created.

SQL> create undo tablespace undotbs3datafile '/oracle/product/oradata/roger/undotbs3.dbf'

2  size 50m autoextend off;

Tablespace created.

SQL>

SQL> conn roger/roger

Connected.

SQL> create table ht_01 as select * fromdba_objects where rownum <10;

Table created.

SQL> delete from ht_01 where rownum<5;

4 rows deleted.

SQL> -----不提交

SQL> selectowner,segment_name,SEGMENT_ID,FILE_ID,BLOCK_ID,STATUS

2  ,tablespace_name from dba_rollback_segs;

OWNER SEGMENT_NAME   SEGMENT_ID    FILE_ID  BLOCK_ID  STATUS   TABLESPACE_NAME

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

SYS   SYSTEM                  0          1          9 ONLINE   SYSTEM

PUBLIC _SYSSMU1$               1          2          9 ONLINE   UNDOTBS1

PUBLIC _SYSSMU2$               2          2         25 ONLINE   UNDOTBS1

PUBLIC _SYSSMU3$               3          2         41 ONLINE   UNDOTBS1

PUBLIC _SYSSMU4$               4          2         57 ONLINE   UNDOTBS1

PUBLIC _SYSSMU5$               5          2         73 ONLINE   UNDOTBS1

PUBLIC _SYSSMU6$               6          2         89 ONLINE   UNDOTBS1

PUBLIC _SYSSMU7$               7          2       105  ONLINE  UNDOTBS1

PUBLIC _SYSSMU8$               8          2        121 ONLINE   UNDOTBS1

PUBLIC _SYSSMU9$               9          2        137 ONLINE   UNDOTBS1

PUBLIC _SYSSMU10$             10          2        153 ONLINE   UNDOTBS1

PUBLIC _SYSSMU11$             11          6          9 OFFLINE  UNDOTBS2

PUBLIC _SYSSMU12$             12          6         25 OFFLINE  UNDOTBS2

PUBLIC _SYSSMU13$             13          6         41 OFFLINE  UNDOTBS2

PUBLIC _SYSSMU14$             14          6         57 OFFLINE  UNDOTBS2

PUBLIC _SYSSMU15$             15          6         73 OFFLINE  UNDOTBS2

PUBLIC _SYSSMU16$             16          6         89 OFFLINE  UNDOTBS2

PUBLIC _SYSSMU17$             17          6        105 OFFLINE  UNDOTBS2

PUBLIC _SYSSMU18$             18          6        121 OFFLINE  UNDOTBS2

PUBLIC _SYSSMU19$             19          6        137 OFFLINE  UNDOTBS2

PUBLIC _SYSSMU20$             20          6        153 OFFLINE  UNDOTBS2

PUBLIC _SYSSMU21$             21          7         9  OFFLINE  UNDOTBS3

PUBLIC _SYSSMU22$             22          7         25 OFFLINE  UNDOTBS3

PUBLIC _SYSSMU23$             23          7         41 OFFLINE  UNDOTBS3

PUBLIC _SYSSMU24$             24          7         57 OFFLINE  UNDOTBS3

PUBLIC _SYSSMU25$             25          7         73 OFFLINE  UNDOTBS3

PUBLIC _SYSSMU26$             26          7         89 OFFLINE  UNDOTBS3

PUBLIC _SYSSMU27$             27          7        105 OFFLINE  UNDOTBS3

PUBLIC _SYSSMU28$             28          7        121 OFFLINE  UNDOTBS3

PUBLIC _SYSSMU29$             29          7        137 OFFLINE  UNDOTBS3

PUBLIC _SYSSMU30$             30          7        153 OFFLINE  UNDOTBS3

31 rows selected.

SQL> selectxidusn,xidslot,xidsqn,ubablk,ubafil,ubarec from v$transaction;

    XIDUSN   XIDSLOT     XIDSQN     UBABLK    UBAFIL     UBAREC

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

        9         13        299        439          2         47

SQL> selectusn,name from v$rollname where usn=9;

      USN NAME

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

        9 _SYSSMU9$

--确定当前正在使用的回滚段

SQL>

SQL>c/file_name/file_name,tablespace_name

  1*select file_id,file_name,tablespace_name from dba_data_files order by 1

SQL> /

   FILE_IDFILE_NAME                                      TABLESPACE_NAME

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

        1 /oracle/product/oradata/roger/system01.dbf      SYSTEM

        2 /oracle/product/oradata/roger/undotbs01.dbf     UNDOTBS1

        3 /oracle/product/oradata/roger/sysaux01.dbf      SYSAUX

        4 /oracle/product/oradata/roger/users01.dbf       USERS

        5 /oracle/product/oradata/roger/roger01.dbf       ROGER

        6 /oracle/product/oradata/roger/undotbs2.dbf      UNDOTBS2

        7 /oracle/product/oradata/roger/undotbs3.dbf      UNDOTBS3



7 rows selected.                                         



SQL>                                                    

SQL> show parameter undo                                 

NAME                                 TYPE        VALUE

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

undo_management                      string      AUTO

undo_retention                       integer     900

undo_tablespace                      string      UNDOTBS1

SQL> alter system setundo_tablespace=undotbs2;

System altered.

SQL> alter database datafile 2 offline;

Database altered.

SQL>

SQL> shutdown abort;

ORACLE instance shut down.

SQL>

SQL>

SQL> startup

ORACLE instance started.

Total System Global Area  167772160 bytes

Fixed Size                  1266392 bytes

Variable Size             104860968 bytes

Database Buffers           58720256 bytes

Redo Buffers                2924544 bytes

Database mounted.

Database opened.

SQL> drop tablespace undotbs1 includingcontents and datafiles;

drop tablespace undotbs1 including contentsand datafiles

*

ERROR at line 1:

ORA-01548: activerollback segment '_SYSSMU9$' found, terminate dropping tablespace

SQL>  ---我们看到报错了 意思是说该回滚段中还有活动事务

SQL> conn roger/roger

Connected.

SQL> show parameter undo

NAME                                 TYPE        VALUE

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

_collect_undo_stats                  boolean     TRUE

_gc_dissolve_undo_affinity           boolean     FALSE

_gc_initiate_undo_affinity           boolean     TRUE

_gc_undo_affinity                    boolean     TRUE

_gc_undo_affinity_locks              boolean     TRUE

_in_memory_undo                      boolean    TRUE

_kcl_undo_grouping                   integer     32

_kcl_undo_locks                      integer     128

_optimizer_undo_changes              boolean     FALSE

_optimizer_undo_cost_change          string      10.2.0.4

_smon_undo_seg_rescan_limit          integer     10

_undo_autotune                       boolean     TRUE

_undo_debug_mode                     integer     0

_undo_debug_usage                    integer     0

_verify_undo_quota                   boolean     FALSE

undo_management                      string      AUTO

undo_retention                       integer     900

undo_tablespace                      string      UNDOTBS2

SQL>

SQL> alter system set"_smu_debug_mode" = 4;

System altered.

SQL> alter rollback segment"_SYSSMU9$" offline;

alter rollback segment"_SYSSMU9$" offline

*

ERROR at line 1:

ORA-01598: rollback segment '_SYSSMU9$' isnot online

SQL> drop rollback segment"_SYSSMU9$";

drop rollback segment "_SYSSMU9$"

*

ERROR at line 1:

ORA-01545: rollback segment '_SYSSMU9$'specified not available

SQL> selectowner,segment_name,SEGMENT_ID,FILE_ID,BLOCK_ID,STATUS

2  from dba_rollback_segs wheresegment_name='_SYSSMU9$';

OWNER SEGMENT_NAME        SEGMENT_ID    FILE_ID   BLOCK_ID STATUS

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

PUBLIC _SYSSMU9$                     9          2        137 NEEDS RECOVERY

SQL>



用如下隐含参数:

_offline_rollback_segments=(_SYSSMU9$)

_corrupted_rollback_segments=(_SYSSMU9$)

讲参数添加到pfile里,在启动



SQL> startup mountpfile='/oracle/pfile.ora';

ORACLE instance started.

Total System Global Area  167772160 bytes

Fixed Size                  1266392 bytes

Variable Size             104860968 bytes

Database Buffers           58720256 bytes

Redo Buffers                2924544 bytes

Database mounted.

SQL> alter database open;

Database altered.

SQL> selectowner,segment_name,SEGMENT_ID,FILE_ID,BLOCK_ID,STATUS

2  from dba_rollback_segs wheresegment_name='_SYSSMU9$';

OWNER SEGMENT_NAME        SEGMENT_ID    FILE_ID   BLOCK_ID STATUS

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

PUBLIC _SYSSMU9$                     9          2        137 NEEDS RECOVERY

SQL> drop rollbacksegment "_SYSSMU9$";

Rollback segment dropped.

SQL>

SQL> drop tablespace undotbs1 includingcontents and datafiles;

Tablespace dropped.

SQL>

SQL> select count(*) from ht_01;

COUNT(*)

----------

         5    ---数据丢失



       这里可能有人会问上面的_undo_debug_mode参数为啥不管用?其实不是没效果,是针对这种情况下,没用而已,对于自动undo管理模式,可以使用该参数来手工删除某个回滚段,前提是该回滚段无活动事务。



方法二: 通过更改数据字典表 来删除回滚段和undotablespace

SQL> show parameter undo

NAME                                 TYPE        VALUE

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

undo_management                      string      AUTO

undo_retention                       integer     900

undo_tablespace                      string      UNDOTBS3

SQL> conn roger/roger

Connected.

SQL> select count(*) from ht_01;

COUNT(*)

----------

        3

SQL> delete from ht_01where rownum <2;

1 row deleted.

SQL> ---不提交

SQL> selectxidusn,xidslot,xidsqn,ubablk,ubafil,ubarec from v$transaction;

   XIDUSN    XIDSLOT     XIDSQN    UBABLK     UBAFIL     UBAREC

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

        2          5        310       345          7          6

SQL> select usn,name from v$rollname whereusn=2;

       USNNAME

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

         2_SYSSMU2$

SQL> alter system setundo_tablespace=undotbs4;

System altered.

SQL> alter database datafile 7 offline;

Database altered.

SQL>

SQL> shutdown abort;

ORACLE instance shut down.

SQL> startup

ORACLE instance started.

Total System Global Area  167772160 bytes

Fixed Size                  1266392 bytes

Variable Size             104860968 bytes

Database Buffers           58720256 bytes

Redo Buffers                2924544 bytes

Database mounted.

Database opened.

SQL> drop tablespace undotbs3 includingcontents and datafiles;

drop tablespace undotbs3 including contentsand datafiles

*

ERROR at line 1:

ORA-01548: active rollback segment'_SYSSMU2$' found, terminate dropping tablespace



SQL> select ts# fromts$ where name='UNDOTBS3';

       TS#

----------

         7

SQL> select file#,block#,TYPE#,TS# fromseg$ where ts#=7;

    FILE#     BLOCK#      TYPE#        TS#

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

        7          9         10          7

        7         25         10          7

        7         41         10          7

        7         57         10          7

        7         73        10          7

        7         89         10          7

        7        105         10          7

        7        121         10          7

        7        137         10          7

        7        153         10          7

        7        265          3          7

        7        281         10          7

12 rows selected.

SQL> selectowner,segment_name,SEGMENT_ID,FILE_ID,BLOCK_ID,STATUS

2  from dba_rollback_segs wherefile_id=7;

OWNER SEGMENT_NAME  SEGMENT_ID    FILE_ID  BLOCK_ID  STATUS

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

PUBLIC _SYSSMU2$              2          7        281 NEEDS RECOVERY

--这里281 不是offline

PUBLIC _SYSSMU21$            21          7          9 OFFLINE

PUBLIC _SYSSMU22$            22         7         25 OFFLINE

PUBLIC _SYSSMU23$            23          7         41 OFFLINE

PUBLIC _SYSSMU24$            24          7         57 OFFLINE

PUBLIC _SYSSMU25$            25          7         73 OFFLINE

PUBLIC _SYSSMU26$            26          7        89  OFFLINE

PUBLIC _SYSSMU27$            27          7        105 OFFLINE

PUBLIC _SYSSMU28$            28          7        121 OFFLINE

PUBLIC _SYSSMU29$            29          7        137 OFFLINE

PUBLIC _SYSSMU30$            30          7        153 OFFLINE

11 rows selected.

SQL>

SQL> update seg$set type# = 3 where ts#=7 and file#=7 and BLOCK#=281;

1 row updated.

SQL> commit;

Commit complete.

SQL> shutdown immediate;

Database closed.

Database dismounted.

ORACLE instance shut down.

SQL> startup

ORACLE instance started.

Total System Global Area  167772160 bytes

Fixed Size                  1266392 bytes

Variable Size             104860968 bytes

Database Buffers           58720256 bytes

Redo Buffers                2924544 bytes

Database mounted.

Database opened.                                                                     

SQL> select US# ,NAME,FILE#,BLOCK# fromundo$ where file#=7;

      US# NAME               FILE#     BLOCK#

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

        1 _SYSSMU1$              7        265

        2 _SYSSMU2$              7        281

       21 _SYSSMU21$             7          9

       22 _SYSSMU22$             7         25

       23 _SYSSMU23$             7         41

       24 _SYSSMU24$             7        57

       25 _SYSSMU25$             7         73

       26 _SYSSMU26$             7         89

       27 _SYSSMU27$             7        105

       28 _SYSSMU28$             7        121

       29 _SYSSMU29$             7        137

        30 _SYSSMU30$             7        153



12 rows selected.         

SQL>

SQL> delete from undo$where ts#=7 and US#=2;

1 row deleted.

SQL> delete from seg$ where ts#=7 andfile#=7 and block#=281;

1 row deleted.

SQL>

SQL> commit;

Commit complete.

SQL> drop rollback segment"_SYSSMU2$";

drop rollback segment "_SYSSMU2$"

*

ERROR at line 1:

ORA-01545: rollback segment '_SYSSMU2$'specified not available



由于我们已经从几个数据字典表中将该段清除了,所以需要用包检查下

SQL> execute hcheck.full

PL/SQL procedure successfully completed.

SQL> drop rollback segment"_SYSSMU2$";

Rollback segment dropped.

SQL>

SQL> drop tablespace undotbs3 includingcontents and datafiles;

drop tablespace undotbs3 including contentsand datafiles

*

ERROR at line 1:

ORA-01561: failed to remove all objects inthe tablespace specified



对于该错误,处理起来就非常容易了,如下:

SQL> update seg$ set type# = 3 wherets#=7;

11 rows updated.

SQL> commit;

Commit complete.

SQL> shutdown immediate;

Database closed.

Database dismounted.

ORACLE instance shut down.

SQL> startup

ORACLE instance started.

Total System Global Area  167772160 bytes

Fixed Size                  1266392 bytes

Variable Size             104860968 bytes

Database Buffers           58720256 bytes

Redo Buffers                2924544 bytes

Database mounted.

Database opened.

SQL> drop tablespace undotbs3 includingcontents and datafiles;

Tablespace dropped.

SQL> ----Drop Tablespace 成功



简单的总结下,其实我们只要通过如下步骤就能轻易的删除:

1.  将回滚段更改为临时段

2.  重启实例

3.  从seg$中删除记录

4.  从undo$中删除记录  



       需要注意一下的是,如果不使用hcheck.full,那么直接drop tablespace可能遇到如下错误:

SQL> drop tablespace undotbs2 includingcontents and datafiles;

drop tablespace undotbs2 including contentsand datafiles

*

ERROR at line 1:

ORA-00600: internal error code, arguments:[ktssdrp1], [5], [6], [25], [], [], [], []



方法三: 使用bbed 修改元数据

SQL> purge   recyclebin;

Recyclebin purged.

SQL> create table ht01 as selectowner,object_name,object_id

2  from dba_objects whereobject_id <100;

Table created.

SQL> select count(*) from ht01;

COUNT(*)

----------

       98

SQL> delete from ht01where object_id <10;

8 rows deleted.

SQL>   ----不提交

SQL> show parameter undo

NAME                                 TYPE        VALUE

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

undo_management                      string      AUTO

undo_retention                       integer     900

undo_tablespace                      string     UNDOTBS4

SQL> selectowner,segment_name,SEGMENT_ID,FILE_ID,BLOCK_ID,STATUS

2  from dba_rollback_segs wheretablespace_name='UNDOTBS4';

OWNER SEGMENT_NAME  SEGMENT_ID    FILE_ID  BLOCK_ID  STATUS

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

PUBLIC _SYSSMU1$              1          2        169 ONLINE

PUBLIC _SYSSMU2$              2          2        185 ONLINE

PUBLIC _SYSSMU3$              3          2          9 OFFLINE

PUBLIC _SYSSMU4$              4          2        25  OFFLINE

PUBLIC _SYSSMU5$              5          2         41 OFFLINE

PUBLIC _SYSSMU6$              6          2         57 OFFLINE

PUBLIC _SYSSMU7$              7          2         73 OFFLINE

PUBLIC _SYSSMU8$              8          2         89 OFFLINE

PUBLIC _SYSSMU10$            10          2        105 OFFLINE

PUBLIC _SYSSMU11$            11          2        121 OFFLINE

PUBLIC _SYSSMU12$            12          2        137 OFFLINE

PUBLIC _SYSSMU31$            31          2       153  OFFLINE

12 rows selected.

SQL> selectxidusn,xidslot,xidsqn,ubablk,ubafil,ubarec from v$transaction;

   XIDUSN    XIDSLOT     XIDSQN    UBABLK     UBAFIL     UBAREC

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

        2          9         3        191          2         10

SQL> select usn,name from v$rollnamewhere usn=2;

      USN NAME

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

        2 _SYSSMU2$

SQL> select file_id,file_name,statusfrom dba_data_files order by 1;

  FILE_ID FILE_NAME                                       STATUS

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

        1 /oracle/product/oradata/roger/system01.dbf      AVAILABLE

        2 /oracle/product/oradata/roger/undotbs4.dbf      AVAILABLE

        3 /oracle/product/oradata/roger/sysaux01.dbf      AVAILABLE

        4 /oracle/product/oradata/roger/users01.dbf       AVAILABLE

        5 /oracle/product/oradata/roger/roger01.dbf       AVAILABLE

        6 /oracle/product/oradata/roger/undotbs5.dbf      AVAILABLE

6 rows selected.

SQL> alter system setundo_tablespace=undotbs5;

System altered.

SQL> alter database datafile 2 offline;

Database altered.

SQL>

SQL> selectowner,SEGMENT_NAME,SEGMENT_TYPE,HEADER_FILE,HEADER_BLOCK

2  from dba_segments wheresegment_name='_SYSSMU2$';

OWNER      SEGMENT_NAME        SEGMENT_TYPE       HEADER_FILEHEADER_BLOCK

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

SYS        _SYSSMU2$            TYPE2 UNDO                   2          185

SQL>



单纯的通过修改undo$的status$字典是无法drop的,如下:

SQL> update undo$ set STATUS$=4 wherefile#=2 and block#=185;

1 row updated.

SQL> commit;

Commit complete.

SQL> select US#,NAME,FILE# ,BLOCK#,STATUS$ from undo$;

      US# NAME                  FILE#     BLOCK#    STATUS$

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

        0 SYSTEM                    1          9          3

        1 _SYSSMU1$                 2        169          2

        2 _SYSSMU2$                 2        185          4

         3 _SYSSMU3$                  2          9          2

        4 _SYSSMU4$                 2         25          2

        5 _SYSSMU5$                 2         41          2

        6 _SYSSMU6$                 2         57          2

        7 _SYSSMU7$                 2         73          2

        8 _SYSSMU8$                 2         89          2

        9 _SYSSMU9$                 2        137          1

       10 _SYSSMU10$                2        105          2

       11 _SYSSMU11$                2        121          2

       12 _SYSSMU12$                2        137          2

       13 _SYSSMU13$                6         41          2

       14 _SYSSMU14$                6         57          2

       15 _SYSSMU15$                 6         73          2

       16 _SYSSMU16$                6         89          2

       17 _SYSSMU17$                6        105          2

       18 _SYSSMU18$                6        121          2

       19 _SYSSMU19$                 6       137          2

       20 _SYSSMU20$                6        153          2

       21 _SYSSMU21$                6          9          3

       22 _SYSSMU22$                6         25          3

       23 _SYSSMU23$                6         41         3

       24 _SYSSMU24$                6         57          3

       25 _SYSSMU25$                6         73          3

       26 _SYSSMU26$                6         89          3

       27 _SYSSMU27$                6        105          3

       28 _SYSSMU28$                6        121          3

       29 _SYSSMU29$                6        137          3

       30 _SYSSMU30$                6        153          3

       31 _SYSSMU31$                2        153          2

32 rows selected.

SQL>

SQL> drop rollback segment"_SYSSMU2$";

drop rollback segment "_SYSSMU2$"

*

ERROR at line 1:

ORA-01545: rollback segment '_SYSSMU2$'specified not available

SQL> alter system set"_smu_debug_mode" = 4;

System altered.

SQL> drop rollback segment"_SYSSMU2$";

drop rollback segment "_SYSSMU2$"

*

ERROR at line 1:

ORA-01545: rollback segment '_SYSSMU2$'specified not available



下面我们通过bbed来修改元数据,也就是直接修改回滚段的状态,将其修改为offline。

SQL> selectdbms_rowid.rowid_relative_fno(rowid) file#,dbms_rowid.rowid_block_number(rowid)blk#

2  from undo$ where file#=2 andblock#=185;

    FILE#       BLK#

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

        1        106

SQL>



BBED> set file 1 block106

       FILE#           1

       BLOCK#          106

BBED> p kdbr

sb2 kdbr[0]                                 @86       8079

sb2 kdbr[1]                                 @88       5234

sb2 kdbr[2]                                 @90      4754

sb2 kdbr[3]                                 @92       6654

sb2 kdbr[4]                                 @94       7860

sb2 kdbr[5]                                 @96       7805

sb2 kdbr[6]                                 @98       6818

sb2 kdbr[7]                                 @100      5123

sb2 kdbr[8]                                 @102      5068

sb2 kdbr[9]                                 @104      5940

sb2 kdbr[10]                                @106      7525

sb2 kdbr[11]                                @108      5013

sb2 kdbr[12]                                @110      4858

sb2 kdbr[13]                                @112      6053

sb2 kdbr[14]                                @114      7309

sb2 kdbr[15]                                @116     7255

sb2 kdbr[16]                                @118      7201

sb2 kdbr[17]                                @120      7146

sb2 kdbr[18]                                @122      7091

sb2 kdbr[19]                                @124      5885

sb2 kdbr[20]                                @126      6981

sb2 kdbr[21]                                @128      5290

sb2 kdbr[22]                                @130      5780

sb2 kdbr[23]                                @132      5726

sb2 kdbr[24]                                @134      5672

sb2 kdbr[25]                                @136      5618

sb2 kdbr[26]                                @138      5564

sb2 kdbr[27]                                @140      5509

sb2 kdbr[28]                                @142     5454

sb2 kdbr[29]                                @144      5399

sb2 kdbr[30]                                @146      5344

sb2 kdbr[31]                                @148      4803

BBED> p *kdbr[2]

rowdata[0]

----------

ub1 rowdata[0]                              @4822     0x2c

BBED>

BBED>

BBED> x /1rnnnnnnnnnnnnnn

rowdata[0]                                  @4822  

----------

flag@4822:0x2c (KDRHFL, KDRHFF, KDRHFH)

lock@4823:0x00

cols@4824:   17

col   0[2] @4825: 2

col   1[9] @4828: -0

col   2[2] @4838: 1

col   3[2] @4841: 2

col   4[3] @4844: 185

col   5[1] @4848: 0

col   6[1] @4850: 0

col   7[1] @4852: 0

col   8[1] @4854: 0

col   9[1] @4856: 0

col  10[2] @4858: 4

col  11[2] @4861: 8

col  12[0] @4864: *NULL*

col  13[0] @4865: *NULL*

col  14[0] @4866: *NULL*

col  15[0] @4867: *NULL*

col  16[2] @4868: 1

BBED> modify /x 02 offset 4860

File: /oracle/product/oradata/roger/system01.dbf(1)

Block: 106              Offsets: 4860 to 5371           Dba:0x0040006a

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

0202c109 ffffffff 02c1022c 001102c1 200a5f535953534d 55333124 02c10202

c10303c2 023604c3 53491901 8002c103 02c102018002c103 02c109ff ffffff02

c1022c00 1102c10d 0a5f5359 53534d55 31322402c10202c1 0303c202 2604c353

49250180 02c10302 c1020180 02c10302 c109ffffffff02c1 022c0011 02c1200a

5f535953 534d5533 312402c1 0202c103 03c2023601800180 01800180 018002c1

0402c109 ffffffff 02c1022c 001102c1 0d0a5f535953534d 55313224 02c10202

c10303c2 02260180 01800180 01800180 02c10402c109ffff ffff02c1 022c0011

02c10c0a 5f535953 534d5531 312402c1 0202c10303c20216 04c35349 1b018002

c10802c1 04018002 c10302c1 09ffffff ff02c1022c001102 c109095f 53595353

4d553824 02c10202 c10302c1 5a04c353 491d018003c20345 03c2033e 018002c1

0302c109 ffffffff 02c1022c 001102c1 08095f535953534d 55372402 c10202c1

0302c14a 04c35349 27018003 c2036403 c2052801 8002c10302c109ff ffffff02

c1023c01 1102c103 095f5359 53534d55 322402c10202c108 03c20352 04c34a3a

1b018003 c2036403 c2031601 8002c106 02c108ffffffff02 c1022c00 1102c102

095f5359 53534d55 312402c1 0202c103 03c2024604c35351 51018003 c2033003

c2035101 8002c103 02c109ff ffffff02 c1022c011102c116 0a5f5359 53534d55

<32 bytes per line>

BBED> sum apply

Check value for File 1, Block 106:

current = 0x32cb, required = 0x32cb

BBED> verify

DBVERIFY - Verification starting

FILE = /oracle/product/oradata/roger/system01.dbf

BLOCK = 106

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

BBED>

SQL> startup

ORACLE instance started.

Total System Global Area  167772160 bytes

Fixed Size                  1266392 bytes

Variable Size             104860968 bytes

Database Buffers           58720256 bytes

Redo Buffers                2924544 bytes

Database mounted.

Database opened.

SQL> select US#,NAME,FILE# ,BLOCK#,STATUS$ from undo$ where file#=2;

      US# NAME                   FILE#     BLOCK#    STATUS$

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

        1 _SYSSMU1$                  2        169          2

        2 _SYSSMU2$                  2        185          1

        3 _SYSSMU3$                  2          9          2

        4 _SYSSMU4$                   2         25          2

        5 _SYSSMU5$                  2         41          2

        6 _SYSSMU6$                  2         57          2

        7 _SYSSMU7$                  2         73          2

        8 _SYSSMU8$                   2         89          2

        9 _SYSSMU9$                  2        137          1

       10 _SYSSMU10$                 2        105          2

       11 _SYSSMU11$                 2        121          2

       12 _SYSSMU12$                  2        137          2

       31 _SYSSMU31$                 2        153          2

13 rows selected.

SQL> drop rollbacksegment "_SYSSMU2$";

Rollback segment dropped.

SQL>    ---成功drop回滚段。

SQL> conn roger/roger        

Connected.                   

SQL> select count(*) from ht01;



COUNT(*)                   

----------                   

       90                   

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