Question

Say I have a model A::B which has_many model C, what do i name the foreign key?

Class A::B
 has_many :c

Class C
 belongs_to :a_b

In the database Table C has a column a_b_id.
This does not work. Any idea what i am missing? the :: are what i am confused about. Thanks!

Answer 1

Since B is in a different namespace, you’ll need to specify it in your class C.

class C < ActiveRecord::Base
  belongs_to :a_b, :class_name => "A::B"
end

since you’re using a_b_id and not b_id, you’ll need to specify the foreign key in A::B

class A::B < ActiveRecord::Base
  has_many :c, :foreign_key => "a_b_id"
end

Alternatively, you could use the following set up to avoid having to specify a foreign key in A::B

class C < ActiveRecord::Base
  belongs_to :b, :class_name => "A::B"
end

class A::B < ActiveRecord::Base
  has_many :c
end

This would require b_id in the table for C