下面是一个触发器的例子：

复制代码 代码如下:

create or replace trigger logon_ip_control

after logon on database

declare

ip STRING(30);

user STRING(30);

begin

SELECT SYS_CONTEXT('USERENV','SESSION_USER') into user from dual;

SELECT SYS_CONTEXT('USERENV','IP_ADDRESS') into ip from dual;

if user='EPAY_USER'

THEN

IF ip not in ('192.168.219.20','192.168.219.22')

THEN raise_application_error(-20001,'User '||user||' is not allowed to connect from '||ip);

END IF;

END IF;

end;

/

该触发器对用户EPAY_USER进行了IP限制（只允许'192.168.219.20','192.168.219.22'，如果需要设置IP段，用%或?代替即可，如'192.168.219.%‘）。

下面看几个例子测试一下：

1）从非允许IP地址登陆 （192.168.219.21），连接失败

复制代码 代码如下:

[oracle@lxdb2 ~]$ sqlplus epay_user@pri

SQL*Plus: Release 11.2.0.3.0 Production on Wed Jul 3 19:23:48 2013

Copyright (c) 1982, 2011, Oracle. All rights reserved.

Enter password:

ERROR:

ORA-00604: error occurred at recursive SQL level 1

ORA-20001: User EPAY_USER is not allowed to connect from 192.168.219.21

ORA-06512: at line 10

2）从允许IP地址登陆（192.168.219.22），连接成功

复制代码 代码如下:

[oracle@lxdb1 ~]$ sqlplus epay_user

SQL*Plus: Release 11.2.0.3.0 Production on Wed Jul 3 11:24:25 2013

Copyright (c) 1982, 2011, Oracle. All rights reserved.

Enter password:

Connected to:

Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production

With the Partitioning, OLAP, Data Mining and Real Application Testing options

3）从本地登陆(192.168.219.23）不受IP限制影响，连接成功

复制代码 代码如下:

[oracle@lxdb1 ~]$ sqlplus epay_user

SQL*Plus: Release 11.2.0.3.0 Production on Wed Jul 3 11:24:25 2013

Copyright (c) 1982, 2011, Oracle. All rights reserved.

Enter password:

Connected to:

Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production

With the Partitioning, OLAP, Data Mining and Real Application Testing options