新增: competition_users计数字段

app/models/competition_user.rb

@@ -34,7 +34,7 @@
 #
 
 class CompetitionUser < ApplicationRecord
-  belongs_to :competition_info
+  belongs_to :competition_info, counter_cache: true
   belongs_to :user
 
   has_many :attachments, as: :container, dependent: :destroy

db/migrate/20250102074748_add_competition_users_count_to_competition_infos.rb

@@ -0,0 +1,5 @@
+class AddCompetitionUsersCountToCompetitionInfos < ActiveRecord::Migration[5.2]
+  def change
+    add_column :competition_infos, :competition_users_count, :integer, default: 0
+  end
+end