利用logminer，恢复delete误删除操作的数据

使用DBA账户操作

1.打开追加日志

SQL>alter database  add supplemental log data;

SQL>select supplemental_log_data_min from v$database;

SUPPLEME

--------
YES

2.记录DML操作前后的SCN

SQL> select * from test;

A

----------

1

2

3

SQL> select dbms_flashback.get_system_change_number from dual;

GET_SYSTEM_CHANGE_NUMBER

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

                 3640931
SQL> delete test;

3 rows deleted

SQL> commit;

Commit complete

SQL> select dbms_flashback.get_system_change_number from dual;

GET_SYSTEM_CHANGE_NUMBER

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

                 3640943

SQL> select * from test;

 A
----------

3.查询当前REDO日志文件，执行logmnr包

SQL> select group#,status from v$log;

    GROUP# STATUS

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

         4 INACTIVE

         5 INACTIVE

         6 CURRENT

SQL> select group#,member from v$logfile where group#=6;

    GROUP# MEMBER

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

         6 F:\REDO\REDO03A.LOG

SQL> exec dbms_logmnr.add_logfile(LogFileName => 'F:\REDO\REDO03A.LOG', Options => dbms_logmnr.new);

PL/SQL procedure successfully completed

SQL> exec dbms_logmnr.start_logmnr(Options =>dbms_logmnr.dict_from_online_catalog,startscn => 3640931,endScn =>3640943);

PL/SQL procedure successfully completed

SQL> col sql_undo for a50;

SQL> col sql_redo for a50;

SQL> set pagesize 1000

SQL> select operation,sql_redo,sql_undo from v$logmnr_contents;

OPERATION                        SQL_REDO                                           SQL_UNDO

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

START                            set transaction read write;                        

DELETE                           delete from "BYS"."TEST" where "A" = '1' and ROWID insert into "BYS"."TEST"("A") values ('1');

                                  = 'AAASA9AAEAAAAEDAAA';                           

 

DELETE                           delete from "BYS"."TEST" where "A" = '2' and ROWID insert into "BYS"."TEST"("A") values ('2');

                                  = 'AAASA9AAEAAAAEDAAB';                           

 

DELETE                           delete from "BYS"."TEST" where "A" = '3' and ROWID insert into "BYS"."TEST"("A") values ('3');

                                  = 'AAASA9AAEAAAAEDAAC';                           

 

COMMIT                           commit;                                            

 

4.使用查出的UNDO SQL恢复误删除的SQL

这里根据UNDO_SQL中语句，把删除的三条数据 TEST表A列VALUES为1和2和3的行进行恢复。

SQL> insert into bys.test values('1');

1 row inserted

SQL> insert into bys.test values('2');

1 row inserted

SQL> insert into bys.test values('3');

1 row inserted

SQL> commit;

Commit complete

SQL> select * from test;

A

----------

1

2

3