educoder/app/models/stage.rb

class Stage < ApplicationRecord
  include Searchable::Dependents::Stage

  belongs_to :subject, counter_cache: true

  has_many :stage_shixuns, -> { order("stage_shixuns.position ASC") }, dependent: :destroy
  has_many :shixuns, :through => :stage_shixuns

  validates :name, length: { maximum: 30 }
  validates :description, length: { maximum: 300 }
end