>I don't see why you need JOIN in this case. Wouldn't following query produce the same result?
>

>SELECT Member.Numero,Member.Nom,Member.Prenom,Member.LastAccess
>	FROM Member 
>	WHERE Member.LastAccess >= @LastAccess 
>		AND Member.Numero = @NoMember
>		AND EXISTS ( SELECT 1 FROM Monitor WHERE Monitor.NoMember2 = @NoMember )
>	ORDER BY 2	
>

I think you wanted to write this:

DECLARE @NoMember Integer
DECLARE @LastAccess DateTime

SET @NoMember=1
SET @LastAccess='2009-02-10 11:46:55'

SELECT Member.Numero,Member.Nom,Member.Prenom,Member.LastAccess
 FROM Member 
 WHERE Member.LastAccess>=@LastAccess 
 AND EXISTS (SELECT 1 FROM Monitor WHERE Monitor.NoMember2=Member.Numero AND Monitor.NoMember=@NoMember)

Is that correct?

If yes, is this an optimized route?