i'm not sure, but i think you can just declare relationship between tables as rails method implemented (has_many / belongs_to) in each models (each model follow each table) and then, create each controller (scaffolding) for each model.
Then, just need after that to make your views and add the routes in the /config/routes.rb file dedicated to do what you need.
Because for each call of url, you need a view (show for one show or index for a list... as teach on every rails tutorials, but this can be defined by your own methods and routes create...); and for each entry create, you need maybe a view for do it (but it is not an obligation).
So, if i real understand your need, this follow exactly what can rails can provide (same reflexion of construction).
For the end, it will probably be the route configuration who can give you precisely what you want.
but... I'm just a newbie... so... i'm not sure to real understand what you want to do and if it is correct vision for resolve it.