diff --git a/app/models/notification.rb b/app/models/notification.rb
index b39fc97ac03..fa6bb664909 100644
--- a/app/models/notification.rb
+++ b/app/models/notification.rb
@@ -248,6 +248,7 @@ end
 #  idx_notifications_speedup_unread_count                       (user_id,notification_type) WHERE (NOT read)
 #  index_notifications_on_post_action_id                        (post_action_id)
 #  index_notifications_on_read_or_n_type                        (user_id,id DESC,read,topic_id) UNIQUE WHERE (read OR (notification_type <> 6))
+#  index_notifications_on_topic_id_and_post_number              (topic_id,post_number)
 #  index_notifications_on_user_id_and_created_at                (user_id,created_at)
 #  index_notifications_on_user_id_and_id                        (user_id,id) UNIQUE WHERE ((notification_type = 6) AND (NOT read))
 #  index_notifications_on_user_id_and_topic_id_and_post_number  (user_id,topic_id,post_number)