Oracle实验：用BBED恢复误删记录的全过程-Mysql Tutorial-php.cn

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Oracle实验：用BBED恢复误删记录的全过程

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Jun 07, 2016 pm 05:14 PM

Oracle实验：用BBED恢复误删记录的全过程,以上是完好的行，accounting所在行显示为2c，那么，到sqlplus，将其删除：

1 准备测试环境：
SQL> create table c as select * from dept;

Table created.

SQL> select * from c;

    DEPTNO DNAME          LOC
---------- -------------- -------------
        10 ACCOUNTING     NEW YORK
        20 RESEARCH       DALLAS
        30 SALES          CHICAGO
        40 OPERATIONS     BOSTON

SQL> select rowid,c.* from c;

ROWID                  DEPTNO DNAME          LOC
------------------ ---------- -------------- -------------
AAAM5/AAEAAAEmEAAA         10 ACCOUNTING     NEW YORK
AAAM5/AAEAAAEmEAAB         20 RESEARCH       DALLAS
AAAM5/AAEAAAEmEAAC         30 SALES          CHICAGO
AAAM5/AAEAAAEmEAAD         40 OPERATIONS     BOSTON

SQL> select get_rowid('AAAM5/AAEAAAEmEAAA') row_id from dual;

ROW_ID
--------------------------------------------------------------------------------
Object# is :52863
Relative_fno is :4
Block number is :18820
Row number is :0

ps:
get_rowid 这个函数是用来获得row_id的详信息，实现如下：
create or replace function get_rowid
(l_rowid in varchar2)
return varchar2
is
ls_my_rowid varchar2(200);
rowid_type number;
object_number number;
relative_fno number;
block_number number;
row_number number;
begin
dbms_rowid.rowid_info(l_rowid,rowid_type,object_number,relative_fno,block_number,row_number);
ls_my_rowid := 'Object# is :'||to_char(object_number)||chr(10)||
'Relative_fno is :'||to_char(relative_fno)||chr(10)||
'Block number is :'||to_char(block_number)||chr(10)||
'Row number is :'||to_char(row_number);
return ls_my_rowid;
end;

登入bbed
[Oracle@localhost ~]$ bbed parfile=bbed.par
Password:

BBED: Release 2.0.0.0.0 - Limited Production on Thu Jun 14 13:09:44 2012

************* !!! For Oracle Internal Use only !!! ***************

BBED> set dba 4,18820
DBA 0x01004984 (16796036 4,18820)

BBED> find /c ACCOUNTING TOP
File: /u01/app/oracle/oradata/ORCL/datafile/o1_mf_users_7wvsw7hg_.dbf (4)
Block: 18820 Offsets: 8169 to 8191 Dba:0x01004984
------------------------------------------------------------------------
4143434f 554e5449 4e47084e 45572059 4f524b02 06483a

BBED> dump /v dba 4,18820 offset 8169 count 23
File: /u01/app/oracle/oradata/ORCL/datafile/o1_mf_users_7wvsw7hg_.dbf (4)
Block: 18820 Offsets: 8169 to 8191 Dba:0x01004984
-------------------------------------------------------
4143434f 554e5449 4e47084e 45572059 l ACCOUNTING.NEW Y
4f524b02 06483a l ORK..H:

BBED> p *kdbr[0] --*kdbr［n］，其中n是row number
rowdata[66]
-----------
ub1 rowdata[66] @8162 0x2c

BBED> dump /v dba 4,18820 offset 8162 count 23
File: /u01/app/oracle/oradata/ORCL/datafile/o1_mf_users_7wvsw7hg_.dbf (4)
Block: 18820 Offsets: 8162 to 8184 Dba:0x01004984
-------------------------------------------------------
2c000302 c10b0a41 43434f55 4e54494e l ,.....ACCOUNTIN
47084e45 572059 l G.NEW Y

以上是完好的行，，accounting所在行显示为2c，那么，到sqlplus，将其删除：

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