SQL> select xid,start_timestamp,operation,undo_sql from flashback_transaction_query where table_name='STUDENT';
XID START_TIMESTAMP OPERATION UNDO_SQL
---------------- --------------- -------------------------------- --------------------------------------------------------------------------------
0F00020002010000 24-1月-15 20:32: UNKNOWN
0F00040002010000 24-1月-15 20:32: UNKNOWN
0F00040002010000 24-1月-15 20:32: UNKNOWN
13000100FE000000 24-1月-15 19:52: UNKNOWN
1400200004010000 24-1月-15 20:32: UNKNOWN
如上图所示的，但是这里查不出来奇怪了。。。。
通过undo_sql来进行回滚事务（就是再做次反向操作）
oracle10g的闪回表：
Oracle10g的闪回表是把表里的数据回退到以前的某个时
刻或者SCN上。
特点：可以在线操作；自动恢复相关的属性，包括索引、
触发器等。
前提：对表启用行迁移。
语法：
flashback table <table_name> to timestamp | scn
Connected as hr@JIAGULUN
SQL> select * from student;
ID NAME AGE
----------- -------------------- -----------
3 zhangsan 21
SQL> alter table student enable row movement;
Table altered
SQL> select dbms_flashback.get_system_change_number from dual;
GET_SYSTEM_CHANGE_NUMBER
------------------------
3143334
SQL> delete from student where id in(1);
0 rows deleted
SQL> delete from student where id in(3);
1 row deleted
SQL> commit;
Commit complete
SQL> flashback table student to scn 3143334;
Done
SQL> select * from student;
ID NAME AGE
----------- -------------------- -----------
3 zhangsan 21
SQL>
注意：sys的表不能闪回。
Connected to Oracle Database 11g Enterprise Edition Release 11.2.0.1.0
Connected as sys@JIAGULUN AS SYSDBA
SQL> select * from student;
ID NAME AGE
----------- -------------------- -----------
1 zhangsan 20
2 lisi 21
3 wangwu 22
SQL> alter table student enable row movement;
Table altered
SQL> select dbms_flashback.get_system_change_number from dual;
GET_SYSTEM_CHANGE_NUMBER
------------------------
3142994
SQL> delete from student where id in(1,2);
2 rows deleted
SQL> commit;
Commit complete
SQL> select * from student;
ID NAME AGE
----------- -------------------- -----------
3 wangwu 22
SQL> flashback table student to scn 3142994;
flashback table student to scn 3142994
ORA-08185: 用户 SYS 不支持闪回
SQL> show user;
User is "SYS"
SQL>
oracle10g的闪回删除：
Oracle10g的闪回删除：可以恢复一个被drop的对象，因
为进行drop时，Oracle先把它放到回收站中。（回收站和操作系统的回收站很相似）
回收站内的信息：show recyclebin
闪回删除：flashback table <table_name> to before drop;
彻底删除：drop table <table_name> purge;
清空回收站: purge recyclebin;
Connected to Oracle Database 11g Enterprise Edition Release 11.2.0.1.0
Connected as hr@JIAGULUN
SQL> purge recyclebin;
Done
SQL> select * from tab;
TNAME TABTYPE CLUSTERID
------------------------------ ------- ----------
ADDRESS TABLE