Symfony DQuery构建器:魔术方法没有'；t选择正确的表格

我有两个实体：具有多对一关系的teacher、subject

(subject many--- one teacher)，它为我创建了第三个表subject_teacher

我有一个创建教师的表格，还有一个创建科目的表格，我可以从选项列表中选择教师。对于每个科目，我想检索每个教师的数据（名字、姓氏、他所教科目的名称）。一个老师可以教一门以上的科目。

在我的控制器中，我正在做：

$teachers = $em->getRepository('AppBundle:Teacher')->findAll(); $subject = $em->getRepository('AppBundle:Subject')->findByTeachers($teachers);

但我得到了错误：

An exception occurred while executing 'SELECT t0.id AS id_1, t0.name AS name_2 FROM subject t0 WHERE subject_teacher.teacher_id IN (?, ?, ?)' with params [49, 50, 51]: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'subject_teacher.teacher_id' in 'where clause'

神奇的方法findByTeachers忘记在FROM子句中添加表subject_teacher？或者我做错了什么。。

主体实体：

<?php
namespace AppBundle'Entity;
use Doctrine'ORM'Mapping as ORM;
/**
 * Subject
 *
 * @ORM'Table()
 * @ORM'Entity
 * @ORM'Entity(repositoryClass="AppBundle'Entity'Repository'SubjectRepository")
 */
class Subject
{
/**
 * @var integer
 *
 * @ORM'Column(name="id", type="integer")
 * @ORM'Id
 * @ORM'GeneratedValue(strategy="AUTO")
 */
private $id;
/**
 * @var string
 *
 * @ORM'Column(name="name", type="string", length=255)
 */
private $name;
/**
 * @ORM'ManyToMany(targetEntity="AppBundle'Entity'Teacher", cascade={"persist"})
 */
private $teachers;
/**
* @ORM'OneToMany(targetEntity="AppBundle'Entity'Event", mappedBy="subject", cascade={"persist"})
*/
private $events;

/**
 * Get id
 *
 * @return integer
 */
public function getId()
{
    return $this->id;
}
/**
 * Set name
 *
 * @param string $name
 *
 * @return Subject
 */
public function setName($name)
{
    $this->name = $name;
    return $this;
}
/**
 * Get name
 *
 * @return string
 */
public function getName()
{
    return $this->name;
}
/**
 * Set classclassRoom
 *
 * @param integer $classRoom
 *
 * @return Subject
 */
public function setClassRoom($classRoom)
{
    $this->classRoom = $classRoom;
    return $this;
}
/**
 * Get classRoom
 *
 * @return integer
 */
public function getClassRoom()
{
    return $this->classRoom;
}
/**
 * Constructor
 */
public function __construct()
{
    $this->events = new 'Doctrine'Common'Collections'ArrayCollection();
    $this->teachers = new 'Doctrine'Common'Collections'ArrayCollection();
}
/**
 * Add event
 *
 * @param 'AppBundle'Entity'Event $event
 *
 * @return Subject
 */
public function addEvent('AppBundle'Entity'Event $event)
{
    $this->events[] = $event;
    return $this;
}
/**
 * Remove event
 *
 * @param 'AppBundle'Entity'Event $event
 */
public function removeEvent('AppBundle'Entity'Event $event)
{
    $this->events->removeElement($event);
}
/**
 * Get events
 *
 * @return 'Doctrine'Common'Collections'Collection
 */
public function getEvents()
{
    return $this->events;
}
/**
 * Get teachers
 *
 * @return string
 */
public function getTeachers()
{
    return $this->teachers;
}
/**
 * Add teacher
 *
 * @param 'AppBundle'Entity'Teacher $teacher
 *
 * @return Subject
 */
public function addTeacher('AppBundle'Entity'Teacher $teacher)
{
    $this->teachers[] = $teacher;
    return $this;
}
/**
 * Remove teacher
 *
 * @param 'AppBundle'Entity'Teacher $teacher
 */
public function removeTeacher('AppBundle'Entity'Teacher $teacher)
{
    $this->teachers->removeElement($teacher);
}

}

教师实体：`

 namespace AppBundle'Entity;
 use Doctrine'ORM'Mapping as ORM;
 /**
  * Teacher
  *
  * @ORM'Table()
  * @ORM'Entity
  */
 class Teacher
 {
/**
 * @var integer
 *
 * @ORM'Column(name="id", type="integer")
 * @ORM'Id
 * @ORM'GeneratedValue(strategy="AUTO")
 */
private $id;
/**
 * @var string
 *
 * @ORM'Column(name="firstName", type="string", length=255)
 */
private $firstName;
/**
 * @var string
 *
 * @ORM'Column(name="lastName", type="string", length=255)
 */
private $lastName;

/**
 * Get id
 *
 * @return integer
 */
public function getId()
{
    return $this->id;
}
/**
 * Set firstName
 *
 * @param string $firstName
 *
 * @return Teacher
 */
public function setFirstName($firstName)
{
    $this->firstName = $firstName;
    return $this;
}
/**
 * Get firstName
 *
 * @return string
 */
public function getFirstName()
{
    return $this->firstName;
}
/**
 * Set lastName
 *
 * @param string $lastName
 *
 * @return Teacher
 */
public function setLastName($lastName)
{
    $this->lastName = $lastName;
    return $this;
}
/**
 * Get lastName
 *
 * @return string
 */
public function getLastName()
{
    return $this->lastName;
}
}
`

/**** CONTROLLER ****/
$subjects = $em->getRepository('AppBundle:Subject')->findAll();

//If you need to threat results inside the controller:
$results = [];
foreach ($subjects as $subject) {
     $results[]['name'] = $subject->getName();
     $results[]['teacher_fistname'] = $subject->getTeachers()->getFirstName();
     $results[]['teacher_lastname'] = $subject->getTeachers()->getLastName();
    /.../
}
return $results;


// If you only want to display results in the view:
return $this->render('your-template.html.twig', ['subjects' => $subjects ]);
/**** And in the view ****/
{% for subject in subjects %}
  Subject: {{ subject.name }}
  Teacher Fistname: {{ subject.teachers.firstname }}
  Teacher Lastname: {{ subject.teachers.lastname }}
  /.../
{% endfor%}