One-to-Many Unidirectional Overlay Problem (Rails)

Question

I have a problem with STI and relationships in ActiveRecord. I think I missed something in class methods, but I don’t know for sure. Below are my models:

class User < ActiveRecord::Base
  has_many :advertisements
end

class Advertisement < ActiveRecord::Base
  belongs_to :user
end

class FreeAdvertisement < Advertisement
end

class PaidAdvertisement < Advertisement
end

Now I want to find all FreeAdvertise under a specific user, for example:

u = User.find_by_username('myself')
@freebies = u.free_advertisements.all

It gives an error:

undefined method `free_advertisements' for #<User:0x2360f18>

I can hack it using u.advertisements.find :all, :conditions, but that’s not what I want to do. Please help me solve this problem. Thanks in advance.

Answer 1

I think you want:

class User < ActiveRecord::Base
  has_many :free_advertisements
  has_many :paid_advertisements
end