Question

This question comes from breaking up a question that was too big.

Users create Events as a Role in a Network. The Events are then connected to both the Role (different Users can occupy that Role when they are hired or fired) as well as the Event. Users that have administrative Roles can access all Events regardless of the Role that created the Event.

It is possible that Role could be destroyed, but the Event will persist as long as the Network exists. (Like if a position is deleted, but they still want the data for retired positions.)

So can the Event both belongs_to a Role and a Network separately? Is that bad rails design? Is there another way to do this? Would I have a special “Retired” role and keep events always tied to a Role and then use belongs_to :network, :through => :role?

Network.rb

class Network < ActiveRecord::Base
  has_many :roles
  has_many :users, :through => :roles
  has_many :events
end

Role.rb

class Role < ActiveRecord::Base
  belongs_to :user
  belongs_to :network
end

Event.rb – Is this right?

class Event < ActiveRecord::Base
  belongs_to :role  
  belongs to :network
end

Answer 1

In my opinion it’s not bad design with your associations (Events belonging to both Role and Network). And I think it’s more confusing to have a “retired Role” than have it NULL. But perhaps you should consider having a column status on the Role rather than deleting it. If the status is not e.g. 1 (if 1 = ok and 2 = inactive as an example) it can’t be used anymore, acting as it was deleted.

It’s difficult to give an advice when you don’t have the whole picture, but, as I said, in my opinion it’s no need for a “retired” Role just to be able to change the associations.