Oracle限制某个数据库帐号只能在特定机器上连入数据库

通过Oracle数据库的触发器实现，例如：TEST为测试账号、绑定的IP为：10.142.244.30
 
CREATE OR REPLACE TRIGGER sys.trg_work_log
AFTER LOGON ON DATABASE
declare
v_program_name varchar2(200);
v_username varchar2(100);
v_ip varchar2(18);
v_error varchar2(1000);
begin
select username,program,SYS_CONTEXT(&＃39;USERENV&＃39;,&＃39;IP_ADDRESS&＃39;)  
into v_username,v_program_name,v_ip
from sys.v_$session where AUDSID = SYS_CONTEXT(&＃39;USERENV&＃39;, &＃39;SESSIONID&＃39;);
if (upper(v_username)=&＃39;TEST&＃39;) then
  if (UPPER(v_program_name) = &＃39;SQLPLUS.EXE&＃39;) then
     if (v_ip = (&＃39;10.142.244.30&＃39;)) then
       RAISE_APPLICATION_ERROR(-20001,&＃39;You are not allowed to connect to the database,err01&＃39;);
         
    end if;
  ELSE
     RAISE_APPLICATION_ERROR(-20001,&＃39;不能使用sqlplus登?&＃39;);
        
  end if;
else
   RAISE_APPLICATION_ERROR(-20001,&＃39;You are not allowed to connect to the database&＃39;);
  
end if;
 
END ;
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