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Question

I'm learning Ruby and just struggling to get my head round associations properly.

I have questions , sections , and then a question_sections table which links the two. A question can belong to multiple sections, and a section can have many questions. Each question is given a weight and an order per section (which is stored in the question_sections table).

Here are my controllers:

class Question < ActiveRecord::Base
    has_many :sections, :through => :question_sections
    belongs_to :section
    has_many :question_sections
    default_scope { order(order: :asc) }

    accepts_nested_attributes_for :section, :reject_if => :all_blank, allow_destroy: true
    accepts_nested_attributes_for :question_sections, :reject_if => :all_blank, allow_destroy: true
end

class Section < ActiveRecord::Base
    has_many :questions, :through => :question_sections
    has_many :question_sections
    has_many :feedbacks

    accepts_nested_attributes_for :feedbacks, :reject_if => :all_blank, :allow_destroy => true
end

class QuestionSection < ActiveRecord::Base
    belongs_to :section
    belongs_to :question

    accepts_nested_attributes_for :section, :reject_if => :all_blank, allow_destroy: true
    accepts_nested_attributes_for :question, :reject_if => :all_blank, allow_destroy: true
end

I want to be able to access the data in the question_sections table from showing the questions.

In my 'show' for questions I have:

  <%= @question.question %>
  <%= @question.question_section.weight %>

But i'm getting:

undefined method `question_section' for #<Question:0x007fda20c72cc8>

Any advice on what I'm doing wrong would be really appreciated.

Answer 1

First of all, change the below code:

class Question < ActiveRecord::Base
    has_many :sections, :through => :question_sections
    has_many :question_sections
    default_scope { order(order: :asc) }

    accepts_nested_attributes_for :section, :reject_if => :all_blank, allow_destroy: true
    accepts_nested_attributes_for :question_sections, :reject_if => :all_blank, allow_destroy: true
end

& for accesssing data , use <%= @question.question_sections.first.weight %>

This is because question sections is an array of hash