I am creating a database for a small internet service provider. I am trying to create a database that associates person information (In the first table) with an IP address (from a second table). The IP addresses are unique in themselves and once an IP address is used for somebody it should never be used again unless that person leaves or requests a change. I already have the table that contains all the IP addresses we want to assign. The IP Address itself is the primary key as it's unique. I want to create a dropdown list that only shows unassigned IP addresses.
So lets say I'm on Person A who has an ip address of 192.168.1.5, and Person B has an IP address of 192.168.1.6. I go to add a new Person C to the database, and click on the dropdown, I want to see it look like this:
Only the unassigned IP addresses are shown.
I have been working on my own trying to figure this out an am at a loss. How can I accomplish this?