# File ar-extensions/lib/ar-extensions/union.rb, line 77
    def count_union(column_name, *args)
      supports_union!
      count_val = calculate_union(:count, column_name, *args)
      (args.length == 1 && args.first[:limit] && args.first[:limit].to_i < count_val) ? args.first[:limit].to_i : count_val
    end