Since a Permit can have only one Vehicle, I would select Permit to go to a Vehicle layout with Driver as a portal.
Why confuse the User with Hieracrhial menus? If it is confusing to the programmer, how about the User.
Each Permit is related to one Vehicle, but each Vehicle may have more than one Driver - and a Driver could be allocated to more than one Vehicle
So, I'm thinking Permit---------<Permit_Vehicle>---------Vehicle>----------<Driver
That would suggest this data model:
I think you need to rethink the flexiblility idea.
Are you authorizing Vehicles to park or Drivers?
Will you revoke a Driver's permit because he is driving an authorized Vehicle he is NOT permitted for?
How will you verify which Driver drove which vehicle?
Does it make a difference if a Driver is permitted for many vehicles?
Thanks Phil and Jim
yep, maybe I need to go back and KISS it !