Question

I’m modeling a lessons table, the lesson belongs to a user, the teacher and creator of the lesson, and also, the lesson can have many students, which are also users.

So it would be something like this

class Lesson < ActiveRecord::Base
  belongs_to :user
  has_many :users
end

I’d like to call the first user teacher, and the collection of users students, I’ve read the documentation at http://guides.rubyonrails.org/association_basics.html but I can’t quite find what I want.

Answer 1

This should have what you want: http://api.rubyonrails.org/classes/ActiveRecord/Associations/ClassMethods.html#method-i-belongs_to

I think you want the class_name option:

class Lesson < ActiveRecord::Base
  belongs_to :teacher, class_name: "User"
  has_many :students, class_name: "User"
end