Pls906 compiler error for on_logon trigger

Question

Hello,
I wrote a PL/SQL program for on_logon trigger. But it has compiler error(no message file, ora-06540 error and pls906 error). The program is as follow:
DECLARE un VARCHAR2(80);
pw VARCHAR2(80);
cn VARCHAR2(80);
BEGIN
/* ** Bring up the logon screen */
Logon_Screen;
/*** Get the username, password and connect string. */
un=Get_application_property(username);
pw=Get_application_property(password);
cn=get_application_property(connect_string);
/*** Log the user onto the database */
IF cn IS NOT NULL THEN
LOGON(un,pw| |'@'| |cn);
ELSE
LOGON(un,pw);
END IF;
END;
Any help is appreciated
null

Answer 1

I tried following
================================================================
SQL> create or replace trigger after_logon_audit
2 AFTER LOGON ON DATABASE
3 WHEN (USER not in ('SYS','SYSTEM')
4 BEGIN
5 INSERT INTO LOGON_AUDIT
6 (log_time,log_user,LOG_IPADDR,LOG_TERMINAL,LOG_MACHINE,LOG_SESSIONID,LOG_OSUSER)
7 ( select SYSDATE, USER, SYS_CONTEXT('USERENV','IP_ADDRESS'), SYS_CONTEXT('USERENV','TERMINAL'),
8 a.machine, SYS_CONTEXT('USERENV','SESSIONID'), a.OSUSER
9 from V$SESSION a, dual
10 where
11 SYS_CONTEXT('USERENV','SESSIONID') = a.AUDSID
12 and SYS_CONTEXT('USERENV','SESSION_USERID') = USER#);
13 COMMIT;
14 RAISE_APPLICATION_ERROR(-20002,'The DB is unavailable');
15 END;
16
17 /
===============================================================
but got the following error message.
========================
AFTER LOGON ON DATABASE
ERROR at line 2:
ORA-04072: invalid trigger type
========================
Problem still persists. :(