# File lib/active_record/persistence.rb, line 232
    def touch(name = nil)
      attributes = timestamp_attributes_for_update_in_model
      attributes << name if name
      unless attributes.empty?
        current_time = current_time_from_proper_timezone
        changes = {}

        attributes.each do |column|
          changes[column.to_s] = write_attribute(column.to_s, current_time)
        end

        @changed_attributes.except!(*changes.keys)
        primary_key = self.class.primary_key
        self.class.unscoped.update_all(changes, { primary_key => self[primary_key] }) == 1
      end
    end