#46

backend/app/models/post.rb

@@ -56,7 +56,7 @@ class Post < ApplicationRecord
 
   def snapshot_tag_names = tags.joins(:tag_name).order('tag_names.name').pluck('tag_names.name')
 
-  def snapshot_parent_post_ids = parents.order(:parent_post_id).pluck(:parent_post_id)
+  def snapshot_parent_post_ids = parents.order(:id).pluck(:id)
 
   def related limit: nil
     ids = post_similarities.order(cos: :desc)