def relink_all(cls, old_file, new_file):
        """Relink all object versions (for a given file) to a new file.

        .. warning::

           Use this method with great care.
        """
        assert old_file.checksum == new_file.checksum
        assert old_file.id
        assert new_file.id

        with db.session.begin_nested():
            ObjectVersion.query.filter_by(file_id=str(old_file.id)).update({
                ObjectVersion.file_id: str(new_file.id)})