protected function getResultSet()
    {
        if (!$this->resultSetPrototype instanceof HydratingResultSet) {
            $resultSetPrototype = new HydratingResultSet;
            $resultSetPrototype->setHydrator($this->getHydrator());
            $resultSetPrototype->setObjectPrototype($this->getModel());
            $this->resultSetPrototype = $resultSetPrototype;
        }

        return clone $this->resultSetPrototype;
    }