def _filter_startswith(self, term, field_name, field_type, is_not):
        """
        Returns a startswith query on the un-stemmed term.

        Assumes term is not a list.
        """
        if field_type == 'text':
            if len(term.split()) == 1:
                term = '^ %s*' % term
                query = self.backend.parse_query(term)
            else:
                term = '^ %s' % term
                query = self._phrase_query(term.split(), field_name, field_type)
        else:
            term = '^%s*' % term
            query = self.backend.parse_query(term)

        if is_not:
            return xapian.Query(xapian.Query.OP_AND_NOT, self._all_query(), query)
        return query