public function putMulti(array $arr_entities)
    {
        // Ensure all the supplied are Entities and have a Kind & Schema
        $this->ensureSchema($arr_entities);

        // Record the Auto-generated Key IDs against the GDS Entities.
        $this->mapAutoIDs($this->upsert($arr_entities));

        // Consume schema, clear kind mapper-map(!)
        $this->obj_schema = null;
        $this->arr_kind_mappers = [];
    }