def _synchronize(self, state, child, associationrow, clearkeys, uowcommit):
        if state is None or (not self.post_update and uowcommit.is_deleted(state)):
            return

        if clearkeys or child is None:
            sync.clear(state, self.parent, self.prop.synchronize_pairs)
        else:
            self._verify_canload(child)
            sync.populate(child, self.mapper, state, self.parent, self.prop.synchronize_pairs)