# Default strategy is to rely on distance strategy provided
        # in vectorstore constructor
        if self._distance_strategy == DistanceStrategy.COSINE:
            return self._cosine_relevance_score_fn
        elif self._distance_strategy == DistanceStrategy.EUCLIDEAN:
            return self._euclidean_relevance_score_fn
        elif self._distance_strategy == DistanceStrategy.MAX_INNER_PRODUCT:
            return self._max_inner_product_relevance_score_fn
        else:
            raise ValueError(
                "No supported normalization function"
                f" for distance_strategy of {self._distance_strategy}."
                "Consider providing relevance_score_fn to PGVector constructor."
            )