Oracle--创建TRIGGER实现跟踪用户登录信息

---创建日志表记录用户登录信息
create  table user_log
(
  user_id         VARCHAR2(30),
  session_id      NUMBER(10),
  host_name       VARCHAR2(30),
  last_module     VARCHAR2(30),
  logon_day       DATE,
  logoff_day      DATE,
  elapsed_minutes NUMBER(10)
);

--创建用户登录之后的触发器统计用户登陆时的信息：

create or replace  trigger logon_trigger
after logon on database
begin
  insert into user_log
  values(
  user,
  sys_context('userenv','sessionid'),
  sys_context('userenv','host'),
  null,
  sysdate,
  null,
  null
  );
  end;

select *　from user_log;

--创建用户登出之前的触发器统计用户登出时的信息：

create or replace  trigger logoff_trigger
  before logoff on database
begin
 update user_log
     set last_module =
         (select module
            from v$session
           where sys_context('USERENV', 'SESSIONID') = audsid)
   where sys_context('USERENV', 'SESSIONID') = session_id;
  update user_log
     set logoff_day = sysdate
   where sys_context('USERENV', 'SESSIONID') = session_id;
  update user_log
     set elapsed_minutes = round((logoff_day - logon_day) * 1440)
   where sys_context('USERENV', 'SESSIONID') = session_id;
end;