Session info via audititng and System trigger?

Question

Hi,
I am using the following logon trigger to store all the session
information into a table "client_info".
When ever the user logon , his session information stores in the
client_info table.This is our requirement.
And when the session logoff its information will be deleted from
the table client_inf via Logoff trigger.
But the problem is that , The information will not be deleted from
the client info table , if the user logoff abnormally from the
database.
How to overcome this issue.
I am using auditing + logon and logoff trigger in order get the
session info.
Any idea will be great.
Regards
Bill>>
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CREATE OR REPLACE TRIGGER trg_client_info
AFTER LOGON ON DATABASE
BEGIN
execute immediate
'INSERT INTO client_info(session_id,client_name,sid,
serial#,workstation,host_name,logon_time , description)
select a.sessionid,a.username , b.sid, b.serial#, a.os_username,
b.machine,b.logon_time,a.comment_text from user_Audit_trail a ,
V$session b
where a.sessionid = b.audsid
and a.username = b.username
and a.sessionid=userenv(''sessionid'')';
commit;
END;
CREATE OR REPLACE TRIGGER logoff_session
BEFORE LOGOFF ON DATABASE
BEGIN
DELETE from client_info where session_id = userenv('sessionid');
commit;
END;

Answer 1

See here for a similar discussion:
LOGOFF TRIGGER for getting Ip address info,etc