Question

I have some issues with the polymorphic associations in Rails 3. My model looks like this:

class Address < ActiveRecord::Base
  belongs_to :contactable, :polymorphic => true  
end

class OrganisationUnit < ActiveRecord::Base
  # some other associations
end

# Subclass of OrganisationUnit
class Company < OrganisationUnit
  has_one :address, :as => :contactable
end

Now, when I want to get the Address of a Company, Rails generates the following SQL-Query:

SELECT `addresses`.* FROM `addresses` WHERE (`addresses`.contactable_id = 1021 AND `addresses`.contactable_type = 'OrganisationUnit') LIMIT 1

In my opinion it’s wrong, because the contactable_type should be “Company”.
Is there any way I can fix this or tell rails that OrganisationUnit is just an abstract base class?

Answer 1

The is an expected behavior. When you link a STI table to a polymorphic association, Rails stores the base class name rather than the inherited class names. The STI type conversion happens after the object lookup by id.