this is not supported in Security Assist.
It would require updating a database table when a user logs in, and again when the user logs out.
The problem is handling the log out part.
There is no 100% full prof way to tell when a user logs out. They could click a log out button, or close the browser, or simply just sit idle and have the session time out. It's easy enough to update the database if the logout button is pressed, but there's no full proof way to update a database when the session times out or the browser is closed.