γϣϯΛಉ࣌ʹ࡞͢Δ • ඞཁʹΑͬͯɺߋ৽ɾআ͞ΕΔ߹ରԠ • 👉 ͜Ε͔ΒՃ͞ΕΔσʔλ৽چͰಉظ͞ΕΔ class Message < ApplicationRecord has_many :photos, as: :imageable has_many :message_photos has_many :renewed_photos, through: :message_photos, source: :photo end class Photo < ApplicationRecord belongs_to :imageable, polymorphic: true has_many :message_photos has_many :messages, through: :message_photos after_create :create_message_photos!, if: - > { imageable.is_a?(Message) } def create_message_photos! message_photos.create!(message: imageable) end end