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模拟数据块更新
SQL> create table t_xifenfei(id number,name varchar2(10)); Table created. SQL> insert into t_xifenfei values(1,'XFF'); 1 row created. SQL> insert into t_xifenfei values(2,'CHF'); 1 row created. SQL> commit; Commit complete. SQL> alter system checkpoint; System altered. SQL> select id,rowid, 2 dbms_rowid.rowid_relative_fno(rowid)rel_fno, 3 dbms_rowid.rowid_block_number(rowid)blockno, 4 dbms_rowid.rowid_row_number(rowid) rowno 5 from t_xifenfei; ID ROWID REL_FNO BLOCKNO ROWNO ---------- ------------------ ---------- ---------- ---------- 1 AAASc+AAEAAAACvAAA 4 175 0 2 AAASc+AAEAAAACvAAB 4 175 1 SQL> select dump(1,'16') from dual; DUMP(1,'16') ----------------- Typ=2 Len=2: c1,2 SQL> select dump(2,'16') from dual; DUMP(2,'16') ----------------- Typ=2 Len=2: c1,3 SQL> select dump('XFF','16') FROM DUAL; DUMP('XFF','16') ---------------------- Typ=96 Len=3: 58,46,46 SQL> SELECT DUMP('CHF','16') FROM DUAL; DUMP('CHF','16') ---------------------- Typ=96 Len=3: 43,48,46 SQL> update t_xifenfei set name='XIFENFEI' where id=1; 1 row updated. SQL> commit; Commit complete. SQL> select dump('XIFENFEI','16') from dual; DUMP('XIFENFEI','16') ------------------------------------- Typ=96 Len=8: 58,49,46,45,4e,46,45,49 SQL> alter system checkpoint; System altered. SQL> select * from t_xifenfei; ID NAME ---------- ---------- 1 XIFENFEI 2 CHF
这里我们对数据库进行了一次更新操作,并且dump出来对应值,为了方便定位到相应记录
bbed查看相关值
[oracle@xifenfei ~]$ bbed listfile=listfile mode=edit password=blockedit BBED: Release 2.0.0.0.0 - Limited Production on Wed Aug 8 20:50:47 2012 Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved. ************* !!! For Oracle Internal Use only !!! *************** BBED> set file 4 block 175 FILE# 4 BLOCK# 175 BBED> map File: /u01/oracle/oradata/ora11g/users01.dbf (4) Block: 175 Dba:0x010000af ------------------------------------------------------------ KTB Data Block (Table/Cluster) struct kcbh, 20 bytes @0 struct ktbbh, 72 bytes @20 struct kdbh, 14 bytes @100 struct kdbt[1], 4 bytes @114 sb2 kdbr[2] @118 ub1 freespace[8031] @122 ub1 rowdata[35] @8153 ub4 tailchk @8188 BBED> p kdbr sb2 kdbr[0] @118 8053 sb2 kdbr[1] @120 8068 BBED> p *kdbr[1] rowdata[15] ----------- ub1 rowdata[15] @8168 0x2c BBED> x /rnc rowdata[15] @8168 ----------- flag@8168: 0x2c (KDRHFL, KDRHFF, KDRHFH) lock@8169: 0x00 cols@8170: 2 col 0[2] @8171: 2 col 1[3] @8174: CHF BBED> p *kdbr[0] rowdata[0] ---------- ub1 rowdata[0] @8153 0x2c BBED> x /rnc rowdata[0] @8153 ---------- flag@8153: 0x2c (KDRHFL, KDRHFF, KDRHFH) lock@8154: 0x02 cols@8155: 2 col 0[2] @8156: 1 col 1[8] @8159: XIFENFEI BBED> set count 64 COUNT 64 <32 bytes per line> BBED> d /v File: /u01/oracle/oradata/ora11g/users01.dbf (4) Block: 175 Offsets: 8153 to 8191 Dba:0x010000af ------------------------------------------------------- 2c020202 c1020858 4946454e 4645492c l ,......XIFENFEI, 000202c1 03034348 462c0002 02c10203 l ......CHF,...... 58464602 068de8 l XFF.... <16 bytes per line>
使用bbed找回历史值
--准备工作,通过dump出来的值,推算出来第一条记录的起点02c10203584646, --在这个值的基础上offset-3得到offset值为8078 BBED> p kdbr sb2 kdbr[0] @118 8053 sb2 kdbr[1] @120 8068 --修改row directory指针位置 BBED> m /x 8e1f File: /u01/oracle/oradata/ora11g/users01.dbf (4) Block: 175 Offsets: 118 to 181 Dba:0x010000af ------------------------------------------------------------------------ 8e1f841f 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 <32 bytes per line> BBED> p kdbr sb2 kdbr[0] @118 8078 sb2 kdbr[1] @120 8068 BBED> sum apply Check value for File 4, Block 175: current = 0xdff8, required = 0xdff8 BBED> verify DBVERIFY - Verification starting FILE = /u01/oracle/oradata/ora11g/users01.dbf BLOCK = 175 Block Checking: DBA = 16777391, Block Type = KTB-managed data block data header at 0xb53cd264 kdbchk: xaction header lock count mismatch trans=2 ilk=1 nlo=0 --提示事务锁错误 Block 175 failed with check code 6108 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[25] ----------- ub1 rowdata[25] @8178 0x2c BBED> d File: /u01/oracle/oradata/ora11g/users01.dbf (4) Block: 175 Offsets: 8178 to 8191 Dba:0x010000af ------------------------------------------------------------------------ 2c000202 c1020358 46460206 8de8 <32 bytes per line> BBED> x /rnc rowdata[25] @8178 ----------- flag@8178: 0x2c (KDRHFL, KDRHFF, KDRHFH) lock@8179: 0x00 --被更新前的记录事务锁标识为0,而更新后的事务锁标识为2 cols@8180: 2 col 0[2] @8181: 1 col 1[3] @8184: XFF --修改事务锁标识为2 BBED> m /x 02 offset 8179 File: /u01/oracle/oradata/ora11g/users01.dbf (4) Block: 175 Offsets: 8179 to 8191 Dba:0x010000af ------------------------------------------------------------------------ 020202c1 02035846 4602068d e8 <32 bytes per line> BBED> set offset 8153 OFFSET 8153 BBED> d File: /u01/oracle/oradata/ora11g/users01.dbf (4) Block: 175 Offsets: 8153 to 8191 Dba:0x010000af ------------------------------------------------------------------------ 2c020202 c1020858 4946454e 4645492c 000202c1 03034348 462c0202 02c10203 58464602 068de8 <32 bytes per line> --把更新后值的事务锁标识改为0 BBED> m /x 00 offset +1 File: /u01/oracle/oradata/ora11g/users01.dbf (4) Block: 175 Offsets: 8154 to 8191 Dba:0x010000af ------------------------------------------------------------------------ 000202c1 02085849 46454e46 45492c00 0202c103 03434846 2c020202 c1020358 46460206 8de8 <32 bytes per line> BBED> sum apply Check value for File 4, Block 175: current = 0xddfa, required = 0xddfa BBED> verify DBVERIFY - Verification starting FILE = /u01/oracle/oradata/ora11g/users01.dbf BLOCK = 175 Block Checking: DBA = 16777391, Block Type = KTB-managed data block data header at 0xb53cd264 kdbchk: the amount of space used is not equal to block size used=42 fsc=0 avsp=8041 dtl=8088 -->提示块的空间使用不正确 Block 175 failed with check code 6110 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 ktbbh struct ktbbh, 72 bytes @20 ub1 ktbbhtyp @20 0x01 (KDDBTDATA) union ktbbhsid, 4 bytes @24 ub4 ktbbhsg1 @24 0x0001273e ub4 ktbbhod1 @24 0x0001273e struct ktbbhcsc, 8 bytes @28 ub4 kscnbas @28 0x0000e88a ub2 kscnwrp @32 0x0002 sb2 ktbbhict @36 2 ub1 ktbbhflg @38 0x32 (NONE) ub1 ktbbhfsl @39 0x00 ub4 ktbbhfnx @40 0x010000a8 struct ktbbhitl[0], 24 bytes @44 struct ktbitxid, 8 bytes @44 ub2 kxidusn @44 0x0006 ub2 kxidslt @46 0x001e ub4 kxidsqn @48 0x000002c6 struct ktbituba, 8 bytes @52 ub4 kubadba @52 0x00c000d9 ub2 kubaseq @56 0x0086 ub1 kubarec @58 0x2a ub2 ktbitflg @60 0x8000 (KTBFCOM) union _ktbitun, 2 bytes @62 sb2 _ktbitfsc @62 2 ub2 _ktbitwrp @62 0x0002 ub4 ktbitbas @64 0x0000e550 struct ktbbhitl[1], 24 bytes @68 struct ktbitxid, 8 bytes @68 ub2 kxidusn @68 0x0006 ub2 kxidslt @70 0x0008 ub4 kxidsqn @72 0x000002c7 struct ktbituba, 8 bytes @76 ub4 kubadba @76 0x00c000da ub2 kubaseq @80 0x0086 ub1 kubarec @82 0x12 ub2 ktbitflg @84 0x2001 (KTBFUPB) union _ktbitun, 2 bytes @86 sb2 _ktbitfsc @86 0 ub2 _ktbitwrp @86 0x0000 ub4 ktbitbas @88 0x0000e88d --所有的_ktbitfsc修改为0 BBED> m /x 00 offset 62 File: /u01/oracle/oradata/ora11g/users01.dbf (4) Block: 175 Offsets: 62 to 125 Dba:0x010000af ------------------------------------------------------------------------ 000050e5 00000600 0800c702 0000da00 c0008600 12000120 00008de8 00000000 00000000 00000001 0200ffff 1600751f 691f691f 00000200 8e1f841f 00000000 <32 bytes per line> BBED> sum apply Check value for File 4, Block 175: current = 0xddf8, required = 0xddf8 BBED> verify DBVERIFY - Verification starting FILE = /u01/oracle/oradata/ora11g/users01.dbf BLOCK = 175 Block Checking: DBA = 16777391, Block Type = KTB-managed data block data header at 0xb53cd264 kdbchk: the amount of space used is not equal to block size used=42 fsc=0 avsp=8041 dtl=8088 Block 175 failed with check code 6110 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 kdbh struct kdbh, 14 bytes @100 ub1 kdbhflag @100 0x00 (NONE) sb1 kdbhntab @101 1 sb2 kdbhnrow @102 2 sb2 kdbhfrre @104 -1 sb2 kdbhfsbo @106 22 sb2 kdbhfseo @108 8053 sb2 kdbhavsp @110 8045 sb2 kdbhtosp @112 8045 --修改kdbhtosp和kdbhavsp值 BBED> m /x 6e1f offset 112 File: /u01/oracle/oradata/ora11g/users01.dbf (4) Block: 175 Offsets: 112 to 175 Dba:0x010000af ------------------------------------------------------------------------ 6e1f0000 02008e1f 841f0000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 <32 bytes per line> BBED> m /x 6e1f offset 110 File: /u01/oracle/oradata/ora11g/users01.dbf (4) Block: 175 Offsets: 110 to 173 Dba:0x010000af ------------------------------------------------------------------------ 6e1f6e1f 00000200 8e1f841f 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 <32 bytes per line> BBED> sum apply Check value for File 4, Block 175: current = 0xddf8, required = 0xddf8 --数据块验证通过 BBED> verify DBVERIFY - Verification starting FILE = /u01/oracle/oradata/ora11g/users01.dbf BLOCK = 175 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
重启数据库
SQL> shutdown abort ORACLE instance shut down. SQL> startup ORACLE instance started. Total System Global Area 313860096 bytes Fixed Size 1344652 bytes Variable Size 251661172 bytes Database Buffers 54525952 bytes Redo Buffers 6328320 bytes Database mounted. Database opened. --找回更新前值 SQL> select * from chf.t_xifenfei; ID NAME ---------- ---------- 1 XFF 2 CHF
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