build_order

# File activerecord/lib/active_record/relation/query_methods.rb, line 1005
    def build_order(arel)
      orders = order_values
      orders = reverse_sql_order(orders) if reverse_order_value

      orders = orders.uniq.reject(&:blank?).flat_map do |order|
        case order
        when Symbol
          table[order].asc
        when Hash
          order.map { |field, dir| table[field].send(dir) }
        else
          order
        end
      end

      arel.order(*orders) unless orders.empty?
    end