protected function loadDefaultMetadata()
    {
        $adapterName = $this->adapter->getPlatform()->getName();
        switch (strtolower($adapterName)) {
            case 'mysql':
                // supported
                break;
            default:
                throw new Exception\UnsupportedFeatureException(__METHOD__ . ":  Adapter '$adapterName' is not yet supported.");
        }
        $this->metadata = $this->driver->getMetadata();
    }