Rails: Concat Two CollectionProxies with two different models

Question

As the title explains, say I have two ActiveRecord::Base models: SatStudentAnswer and ActStudentAnswer.

I have a Student model

has_many :act_student_answers
has_many :sat_student_answers

I would like to create a collection proxy that concats them together so I can query all student answers together.

student.sat_student_answers.concat(student.act_student_answers)

However I get an ActiveRecord::AssociationTypeMismatch: SatStudentAnswer(#70111600189260) expected, got ActStudentAnswer(#70111589566060) error.

Is there a way to create a collection proxy with two different models so I can continue using the Active Record query interface? If not, what would be the best way to solve this problem?

Thank you for the help!

Answer 1

As far as I know, there isn't way to create Rails AR:Relation with different models in it (I digged in this issue when I needed to create newsfeed with different kind of posts). My solution wasn't very beautiful, but was working: I've created additional model with polymorphic has_many. You could query collection of these new defined models and distinguish sat_answers and act_answers by field answer_type.