Programming access to users and roles table?

[rbenedict]

We would like to be able to programatically (.NET, C#) to add a user to the Alfresco MySQL database and to add their assigned role as well (we've been able to do it with Drupal, also using a MySQL database).  However, I haven't been able to determine where these 2 tables might be in the MySQL database.  So I guess I have 2 questions:
1. Is it possible to programatically add users and their assigned role to the Alfresco MySQL database?
2. If so, what tables? 
Thanks,
Roger

[mrogers]

Yes, its possible to fiddle with the database directly.   But the prefered route is to use one of the public API's.