#228

backend/app/models/post_similarity.rb

@@ -1,4 +1,6 @@
 class PostSimilarity < ApplicationRecord
+  self.primary_key = :post_id, :target_post_id
+
   belongs_to :post, class_name: 'Post', foreign_key: 'post_id'
   belongs_to :target_post, class_name: 'Post', foreign_key: 'target_post_id'
 end

backend/app/models/tag_similarity.rb

@@ -1,4 +1,6 @@
 class TagSimilarity < ApplicationRecord
+  self.primary_key = :tag_id, :target_tag_id
+
   belongs_to :tag, class_name: 'Tag', foreign_key: 'tag_id'
   belongs_to :target_tag, class_name: 'Tag', foreign_key: 'target_tag_id'
 end