    # File lib/active_record/batches.rb, line 55
          def find_in_batches(options = {})
            raise "You can't specify an order, it's forced to be #{batch_order}" if options[:order]
            raise "You can't specify a limit, it's forced to be the batch_size"  if options[:limit]

            start = options.delete(:start).to_i
            batch_size = options.delete(:batch_size) || 1000

            with_scope(:find => options.merge(:order => batch_order, :limit => batch_size)) do
              records = find(:all, :conditions => [ "#{table_name}.#{primary_key} >= ?", start ])

              while records.any?
                yield records

                break if records.size < batch_size
                records = find(:all, :conditions => [ "#{table_name}.#{primary_key} > ?", records.last.id ])
              end
            end
          end