如果你不小心覆盖了之前的存储过程，那得赶紧闪回，时长越长闪回的可能性越小，下面为大家介绍下恢复原理

如果你不小心覆盖了之前的存储过程，那得赶紧闪回，时长越长闪回的可能性越小。原理很简单，存储过程的定义就是数据字典，修改数据字典跟修改普通表的数据没有区别，此时会把修改前的内容放到undo中，我们可以根据这一点来进行闪回，所以我说要尽快，要不然找不回来了。下面我们来做一个实验：

1.在用户TEST下14:31下建立存储过程

代码如下:

create or replace procedure GG_TEST

as l_cnt number;

begin

for i in 1 .. 10000

loop

execute immediate 'select count(*) from t where x = ' || i into l_cnt;

end loop;

end;

2.在用户TEST下在14:33下删除存储过程

代码如下:

drop procedure GG_TEST;

3.登录到sys账户下

代码如下:

create table p_temp as

select *

from dba_source as of timestamp TO_TIMESTAMP('2014-05-04 14:33:00', 'YYYY-MM-DD HH24:MI:SS')

where TYPE = 'PROCEDURE'

And owner = 'TEST'

And Name = 'GG_TEST';

select text

from p_temp

where name like upper('%GG_TEST%')

and owner = 'TEST'

order by line;

TEXT

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

procedure GG_TEST

as l_cnt number;

begin

for i in 1 .. 10000

loop

execute immediate 'select count(*) from t where x = ' || i into l_cnt;

end loop;

end;

更多信息请查看IT技术专栏