:param diff: The table diff
        :type diff: orator.dbal.table_diff.TableDiff

        :rtype: dict

def _get_primary_index_in_altered_table(self, diff):
        """
        :param diff: The table diff
        :type diff: orator.dbal.table_diff.TableDiff

        :rtype: dict
        """
        primary_index = {}

        for index in self._get_indexes_in_altered_table(diff).values():
            if index.is_primary():
                primary_index = {index.get_name(): index}

        return primary_index