# File lib/yaml_db/serialization_helper.rb, line 203
      def self.sort_keys(table)
        first_column, second_column = table_column_names(table)

        if [first_column, second_column].all? { |name| name =~ /_id$/ }
          [Utils.quote_column(first_column), Utils.quote_column(second_column)]
        else
          [Utils.quote_column(first_column)]
        end
      end