# File lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 662
      def remove_references(*args)
        options = args.extract_options!
        polymorphic = options.delete(:polymorphic)
        args.each do |col|
          @base.remove_column(@table_name, "#{col}_id")
          @base.remove_column(@table_name, "#{col}_type") unless polymorphic.nil?
        end
      end