def saved_attributes_to_fetch(operation)
      # only fetch a create, not an update (note that subclasses can override this condition)
      if operation.type == :create or operation.autogenerated? then
        # Filter the class saved fetch attributes for content.
        self.class.saved_attributes_to_fetch.select { |pa| not send(pa).nil_or_empty? }
      else
        Array::EMPTY_ARRAY
      end
    end
def saved_attributes_to_fetch(operation)
      # only fetch a create, not an update (note that subclasses can override this condition)
      if operation.type == :create or operation.autogenerated? then
        # Filter the class saved fetch attributes for content.
        self.class.saved_attributes_to_fetch.select { |pa| not send(pa).nil_or_empty? }
      else
        Array::EMPTY_ARRAY
      end
    end
Returns this domain object's attributes which must be fetched to reflect the database state.
 This default implementation returns the {Propertied#autogenerated_logical_dependent_attributes}
 if this domain object does not have an identifier, or an empty array otherwise.
 Subclasses can override to relax or restrict the condition.

 @quirk caCORE the auto-generated criterion is a necessary but not sufficient condition
   to determine whether a save caCORE result reflects the database state. Example:
   * caTissue SCG event parameters are not auto-generated on SCG create if the SCG collection
     status is Pending, but are auto-generated on SCG update if the SCG status is changed
     to Complete. By contrast, the SCG specimens are auto-generated on SCG create, even if
     the status is +Pending+.
   The caBIG application can override this method in a Database subclass to fine-tune the
   fetch criteria. Adding a more restrictive {#fetch_saved?} condition will will improve
   performance but not change functionality.

 @quirk caCORE a saved attribute which is cascaded but not fetched must be fetched in
   order to reflect the database identifier in the saved object.

 @param [Database::Operation] the save operation
 @return [<Symbol>] whether this domain object must be fetched to reflect the database state