bbed修改itl值，手动提交事务

发布时间：2020-08-10 23:57:12 作者：7343696
来源：网络阅读：727

数据库的版本是11.2.0.4

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1，数据库版本

www.htz.pw > select * from v$version;

BANNER

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

Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit 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

2，创建测试表

www.htz.pw > create table scott.htz tablespace users as select * from dba_objects where rownum<2;

Table created.

www.htz.pw > select rowid from scott.htz;

ROWID

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

AAASkGAAEAAABkzAAA

www.htz.pw > @rowid_to_info.sql

Enter value for rowid: AAASkGAAEAAABkzAAA

ROWID_TYPE: 1

OBJECT_NUMBER: 76038

RELATIVE_FNO: 4

BLOCK_NUMBER: 6451

ROW_NUMBER: 0

PL/SQL procedure successfully completed.

3，模拟实验

3.1 更新行记录

www.htz.pw > conn scott/oracle

Connected.

www.htz.pw > select owner from htz;

OWNER

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

SYS

www.htz.pw > update htz set owner='HUANGTINGZHONG';

1 row updated.

3.2 将BUFFER_CACHE中的块刷到数据文件中

这里另外打开一个窗口来执行

www.htz.pw > alter system flush buffer_cache;

System altered.

www.htz.pw > select owner from scott.htz;

OWNER

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

SYS

3.3 DUMP数据文件中的块

这里dump块的目的是为了查看值是否发生了变化，以及行的标识符信息

www.htz.pw > select file_name from dba_data_files;

FILE_NAME

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

/oracle/app/oracle/oradata/orcl1123/users01.dbf

/oracle/app/oracle/oradata/orcl1123/undotbs1.dbf

/oracle/app/oracle/oradata/orcl1123/sysaux01.dbf

/oracle/app/oracle/oradata/orcl1123/system01.dbf

/oracle/app/oracle/oradata/orcl1123/undotbs2.dbf

/oracle/app/oracle/oradata/orcl1123/htz01.dbf

/oracle/app/oracle/oradata/orcl1123/tbs_data.dbf

/oracle/app/oracle/oradata/orcl1123/undotbs3.dbf

www.htz.pw > @dump_block.sql

Enter value for datafile: 4

Enter value for block_id: 6451

old 1: alter system dump datafile &datafile block &block_id

new 1: alter system dump datafile 4 block 6451

System altered.

在trace文件中可以看到如下的信息

Block header dump: 0x01001933

Object id on Block? Y

seg/obj: 0x12906 csc: 0x00.24e77c itc: 3 flg: E typ: 1 - DATA

brn: 0 bdba: 0x1001930 ver: 0x01 opc: 0

inc: 0 exflg: 0

Itl Xid Uba Flag Lck Scn/Fsc

0x01 0xffff.000.00000000 0x00000000.0000.00 C--- 0 scn 0x0000.0024e747

0x02 0x000d.003.000000d7 0x0140026c.0202.04 ---- 1 fsc 0x0000.00000000

0x03 0x0000.000.00000000 0x00000000.0000.00 ---- 0 fsc 0x0000.00000000

bdba: 0x01001933

data_block_dump,data header at 0x2a97c20a7c

===============

tsiz: 0x1f80

hsiz: 0x14

pbl: 0x2a97c20a7c

76543210

flag=--------

ntab=1

nrow=1

frre=-1

fsbo=0x14

fseo=0x1edb

avsp=0x1f14

tosp=0x1f14

0xe:pti[0] nrow=1 offs=0

0x12:pri[0] offs=0x1edb

block_row_dump:

tab 0, row 0, @0x1edb

tl: 88 fb: --H-FL-- lb: 0x2 cc: 14

col 0: [14] 48 55 41 4e 47 54 49 4e 47 5a 48 4f 4e 47

col 1: [ 5] 49 43 4f 4c 24

col 2: *NULL*

col 3: [ 2] c1 15

col 4: [ 2] c1 03

col 5: [ 5] 54 41 42 4c 45

col 6: [ 7] 78 6f 09 11 0a 2f 0e

col 7: [ 7] 78 6f 09 11 0a 3b 01

col 8: [19] 32 30 31 31 2d 30 39 2d 31 37 3a 30 39 3a 34 36 3a 31 33

col 9: [ 5] 56 41 4c 49 44

col 10: [ 1] 4e

col 11: [ 1] 4e

col 12: [ 1] 4e

col 13: [ 2] c1 02

4,bbed修改块的相关的内容

其实bbed只需要改2个地址，一个地方是改itl中的flg，更改为提交，另一个地方是清除行中的itl的值

BBED> p ktbbh

struct ktbbh, 96 bytes @20

ub1 ktbbhtyp @20 0x01 (KDDBTDATA)

union ktbbhsid, 4 bytes @24

ub4 ktbbhsg1 @24 0x00012906

ub4 ktbbhod1 @24 0x00012906

struct ktbbhcsc, 8 bytes @28

ub4 kscnbas @28 0x0024e77c

ub2 kscnwrp @32 0x0000

sb2 ktbbhict @36 3

ub1 ktbbhflg @38 0x32 (NONE)

ub1 ktbbhfsl @39 0x00

ub4 ktbbhfnx @40 0x01001930

struct ktbbhitl[0], 24 bytes @44

struct ktbitxid, 8 bytes @44

ub2 kxidusn @44 0xffff

ub2 kxidslt @46 0x0000

ub4 kxidsqn @48 0x00000000

struct ktbituba, 8 bytes @52

ub4 kubadba @52 0x00000000

ub2 kubaseq @56 0x0000

ub1 kubarec @58 0x00

ub2 ktbitflg @60 0x8000 (KTBFCOM)

union _ktbitun, 2 bytes @62

sb2 _ktbitfsc @62 0

ub2 _ktbitwrp @62 0x0000

ub4 ktbitbas @64 0x0024e747

struct ktbbhitl[1], 24 bytes @68

struct ktbitxid, 8 bytes @68

ub2 kxidusn @68 0x000d

ub2 kxidslt @70 0x0003

ub4 kxidsqn @72 0x000000d7

struct ktbituba, 8 bytes @76

ub4 kubadba @76 0x0140026c

ub2 kubaseq @80 0x0202

ub1 kubarec @82 0x04

ub2 ktbitflg @84 0x0001 (NONE)

union _ktbitun, 2 bytes @86

sb2 _ktbitfsc @86 0

ub2 _ktbitwrp @86 0x0000

ub4 ktbitbas @88 0x00000000

BBED> set mode edit

MODE Edit

BBED> set count 16

COUNT 16

这里有一点需要注意的是，测试平台是X86的，如果是小机需要注意了，有一点不一样的地方，不需要高低位转换

BBED> modify /x 0080 offset 84

Warning: contents of previous BIFILE will be lost. Proceed? (Y/N) y

File: /oracle/app/oracle/oradata/orcl1123/users01.dbf (0)

Block: 6451 Offsets: 84 to 99 Dba:0x00000000

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

00800000 00000000 00000000 00000000

<32 bytes per line>

BBED> p ktbbh.ktbbhitl[1]

struct ktbbhitl[1], 24 bytes @68

struct ktbitxid, 8 bytes @68

ub2 kxidusn @68 0x000d

ub2 kxidslt @70 0x0003

ub4 kxidsqn @72 0x000000d7

struct ktbituba, 8 bytes @76

ub4 kubadba @76 0x0140026c

ub2 kubaseq @80 0x0202

ub1 kubarec @82 0x04

ub2 ktbitflg @84 0x8000 (KTBFCOM)

union _ktbitun, 2 bytes @86

sb2 _ktbitfsc @86 0

ub2 _ktbitwrp @86 0x0000

ub4 ktbitbas @88 0x00000000

这里可以看到，下面报了行为的itl值有问题

BBED> verify

DBVERIFY - Verification starting

FILE = /oracle/app/oracle/oradata/orcl1123/users01.dbf

BLOCK = 6451

Block Checking: DBA = 16783667, Block Type = KTB-managed data block

data header at 0x2a98b8727c

kdbchk: row locked by non-existent transaction

table=0 slot=0

lockid=2 ktbbhitc=3

Block 6451 failed with check code 6101

DBVERIFY - Verification complete

Total Blocks Examined : 1

Total Blocks Processed (Data) : 1

Total Blocks Failing (Data) : 1

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> p *kdbr[0]

rowdata[0]

----------

ub1 rowdata[0] @8023 0x2c

BBED> set offset 8023

OFFSET 8023

BBED> dump

File: /oracle/app/oracle/oradata/orcl1123/users01.dbf (0)

Block: 6451 Offsets: 8023 to 8038 Dba:0x00000000

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

2c020e0e 4855414e 4754494e 475a484f

<32 bytes per line>

BBED> modify /x 2c00

File: /oracle/app/oracle/oradata/orcl1123/users01.dbf (0)

Block: 6451 Offsets: 8023 to 8038 Dba:0x00000000

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

2c000e0e 4855414e 4754494e 475a484f

<32 bytes per line>

BBED> sum apply

Check value for File 0, Block 6451:

current = 0xbebc, required = 0xbebc

下面再也没有报错了

BBED> verify

DBVERIFY - Verification starting

FILE = /oracle/app/oracle/oradata/orcl1123/users01.dbf

BLOCK = 6451

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

6，查看bbed更改后的数据

另外开一个窗口来查看表中的数据

www.htz.pw > select owner from scott.htz;

OWNER

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

HUANGTINGZHONG

这里可以看到数据已经被更新了。

不过需要注意的是在update窗口，执行rollback语句，还是可以回退的

如果在原窗口执行rollback命令的时候，仍然会回滚记录的。

www.htz.pw > rollback;

Rollback complete.

www.htz.pw > select owner from scott.htz;

OWNER

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

SYS

bbed修改itl值，手动提交事务

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