DBMS ALERT package

• Hello everybody,

Is there someone able to help me ?

I have a problem with DBMS_ALERT package semantic and I would be very  grateful if somebody can help me. It's urgent and important for hypothesis  of our work (knowledge about commit of transactions) The documentation says that if there are several signal call, for lets say  'my-signal', and if the listening operation doesn't listen very often I  will receive only the most recent one. That's OK, but I don't understand what does it mean in respect with transactions. Let's imagine an example with simplified syntax:

one program doing

	insert into Emp 
	insert into Emp 
	commit
	insert into Emp
	commit

And another one         

	while true loop
		dbms_alert.waitone('my_signal', mesg, status)
		if status=0 then
		DBMS_OUTPUT.put_line(mesg);		
		end if;
	end loop

Knowing that I have a trigger

	CREATE TRIGGER MY_TRIGGER
	AFTER INSERT or UPDATE ON EMP
	DECALRE
	send_mesg varchar2;
	BEGIN 
		send_mesg=new.EMPNO;
		DBMS_ALERT.signal('my_signal', send_mesg);	
	END;

THe question is : how much signals I do receive: the last one, the second and the third or the three of them?

And also, alerts are signalled after the commit-that's ok- but when is  it exactly in respect with subsequent transactions from the same session?

Thanks for answer

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
  Maja Matulovic - maja_at_rodin.inria.fr

  INRIA Rocquencourt, projet Rodin           
  BP 105,  78 153 Le Chesnay  Cedex                 
  Phone: (33 1) 39 63 57 44