class Question < ActiveRecord::Base attr_accessible :title, :global, :answers_attributes, :answer_ids, :question_type_id belongs_to :question_type has_and_belongs_to_many :conferences has_many :qanswers, dependent: :delete_all has_many :answers, through: :qanswers, dependent: :delete_all validates :title, presence: true validates :answers, presence: true accepts_nested_attributes_for :answers, allow_destroy: true end