#99

backend/app/models/tag.rb

@@ -73,6 +73,8 @@ class Tag < ApplicationRecord
 
   def has_wiki = wiki_page.present?
 
+  def material_id = materials.first&.id
+
   def self.tagme
     @tagme ||= find_or_create_by_tag_name!('タグ希望', category: :meta)
   end