public static function getAllComboSetsForPostId($postId) {
        global $wpdb;

        $skust = usces_get_tablename('usces_skus');
        $skuMetaIds = $wpdb->get_results(
            $wpdb->prepare(
                "SELECT meta_id FROM {$skust} WHERE post_id = %d",
                (int)$postId
            ),
            ARRAY_N
        );
        $combos = [];
        foreach ($skuMetaIds as $metaId) {
            if (!isset($metaId[0])) {
                continue;
            }
            $skuMetaId = $metaId[0];
            $combo = self::getComboSetBySkuMetaId($skuMetaId);
            if ($combo instanceof GenericError) {
                $combo = null;
            }
            $combos[$skuMetaId] = $combo;
        }

        return $combos;
    }