Discriminator column has no table alias

/**
 * @Orm\Entity
 * @Orm\Table(name="resource")
 * @Orm\InheritanceType("SINGLE_TABLE")
 * @Orm\DiscriminatorColumn(name="type", type="string")
 * @Orm\DiscriminatorMap({"Container" = "Container", "News"="News"})
 */
abstract class Resource
{
}

$em->getRepository('News')->find($id)
/**
* generate SQL like this: 
* SELECT t0.id AS id1, t0.name AS name2, type FROM resource t0 WHERE t0.id = ? AND t0.type IN ('News')
*/

SELECT t0.id AS id1, t0.name AS name2, t0.type FROM resource t0 WHERE t0.id = ? AND t0.type IN ('News')