Php 为什么我能'；连接两个表时，无法在原则中获取实体

以下是我的实体类别模型的一些信息：

设备细节实体

namespace Application\Entity;

use Doctrine\ORM\Mapping as ORM;

/**
* Application\Entity\EquipmentDetail
*
* @ORM\Table(name="EQUIPMENT_DETAIL")
* @ORM\Entity
*/
class EquipmentDetail extends \Application\Entity\Base\BaseEntity
{
/**
 * @var integer $equipmentDetailId
 *
 * @ORM\Column(name="EQUIPMENT_DETAIL_ID", type="integer", nullable=false)
 * @ORM\Id
 * @ORM\GeneratedValue(strategy="IDENTITY")
 */
private $equipmentDetailId;

/**
 * @var string $description
 *
 * @ORM\Column(name="DESCRIPTION", type="text", nullable=true)
 */
private $description;

/**
 * @var integer $active
 *
 * @ORM\Column(name="ACTIVE", type="integer", nullable=true)
 */
private $active;

/**
 * @var Application\Entity\Equipment
 *
 * @ORM\ManyToOne(targetEntity="Application\Entity\Equipment")
 * @ORM\JoinColumns({
 *   @ORM\JoinColumn(name="EQUIPMENT_ID",                                               referencedColumnName="EQUIPMENT_ID")
 * })
 */
private $equipment;

/**
 * @var Application\Entity\EquipmentProperty
 *
 * @ORM\ManyToOne(targetEntity="Application\Entity\EquipmentProperty")
 * @ORM\JoinColumns({
 *   @ORM\JoinColumn(name="EQUIPMENT_PROPERTY_ID", referencedColumnName="EQUIPMENT_PROPERTY_ID")
 * })
 */
private $equipmentProperty;

我也有

\Application\Entity\Base\BaseEntity

及

所有模型类都是返回真实体类，在其他情况下工作良好

在其他情况下，它可以正常工作，例如：

$propertyType = $this->getTypePropertyModel()->createQueryBuilder('t')->join('t.equipmentType', 'eq')
                    ->where('eq.equipmentTypeId=:typeId')->setParameter('typeId', $typeId)->getQuery()->getResult();

但当我创建querybuilder并连接两个表时，我无法得到结果。我尝试了以下多种方法：

$detail = $this->getEquipmentDetailModel()->getEntityManager()
                    ->createQuery('SELECT d FROM \Application\Entity\EquipmentDetail d '
                            . 'JOIN d.equipment e JOIN d.equipmentProperty ep '
                            . 'WHERE (e.equipmentId = 3130'
                            . 'AND ep.equipmentPropertyId =2'
                            . '')
                    ->getResult();

或

或

或

我得到了一个错误

"Fatal error: Call to a member function getDescription() on a non-object in...." 

调用$detail->getDescription（）时。 我确信，我在数据库中记录了设备的详细信息，信息如下：

EQUIPMENT_DETAIL_ID : 45
EQUIPMENT_ID : 3130
EQUIPMENT_PROPERTY_ID : 2
DESCRIPTION :Olala
ACTIVE : 1

当我使用：

$detail = $this->getEquipmentDetailModel()->find(45);

请告诉我为什么我不能得到结果，或者如果我没有提供足够的信息

                $detail = $this->getEquipmentDetailModel()->createQueryBuilder('d')
                            ->innerJoin('d.equipment', 'e')
                            ->innerJoin('d.equipmentProperty', 'ep')
                            ->where('e.equipmentId = :ID')
                            ->andWhere('ep.equipmentPropertyId =:epID')
                            ->setParameter('ID', 3130)
                            ->setParameter('epID', 2)
                            ->getQuery()->setMaxResults(1)->getResult();

"Fatal error: Call to a member function getDescription() on a non-object in...." 

EQUIPMENT_DETAIL_ID : 45
EQUIPMENT_ID : 3130
EQUIPMENT_PROPERTY_ID : 2
DESCRIPTION :Olala
ACTIVE : 1

$detail = $this->getEquipmentDetailModel()->find(45);