Question

查询有问题。我有3个定义如下的实体：

类别实体

class Category
{
    /**
     * @ORM\Id()
     * @ORM\GeneratedValue()
     * @ORM\Column(type="integer")
     */
    private $id;

    //...

    /**
     * @var Product[]
     *
     * @ORM\ManyToMany(targetEntity="App\Entity\Product", mappedBy="categories")
     */
    private $products;

    //...
}

产品实体

class Product
{
    /**
     * @var int
     *
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="IDENTITY")
     * @ORM\Column(type="integer")
     */
    private $id;

    //...

    /**
     * @var Collection
     *
     * @ORM\ManyToMany(targetEntity="App\Entity\Category", inversedBy="products")
     * @ORM\JoinTable(name="product_category",
     *   joinColumns={
     *     @ORM\JoinColumn(name="id_product", referencedColumnName="id", nullable=false)
     *   },
     *   inverseJoinColumns={
     *     @ORM\JoinColumn(name="id_category", referencedColumnName="id", nullable=false)
     *   }
     * )
     */
    private $categories;

    /**
     * @var Provider
     *
     * @ORM\ManyToOne(targetEntity="App\Entity\Provider", inversedBy="products")
     * @ORM\JoinColumns({
     *   @ORM\JoinColumn(name="id_provider", referencedColumnName="id", nullable=false)
     * })
     */
    private $provider;

    //...
}

提供商实体

class Provider
{
    /**
     * @var int
     *
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="IDENTITY")
     * @ORM\Column(type="integer")
     */
    private $id;

    //...

    /**
     * @var Product[]
     *
     * @ORM\OneToMany(targetEntity="App\Entity\Product", mappedBy="provider", orphanRemoval=true, cascade={"all"})
     */
    private $products;

    //...
}

我想查询供应商管理的所有产品类别。所以我试试这个：

class CategoryRepository extends ServiceEntityRepository
{
    public function __construct(ManagerRegistry $registry)
    {
        parent::__construct($registry, Category::class);
    }

    public function findByProvider(Provider $provider)
    {
        $qb = $this->createQueryBuilder('c');

        return $qb->leftJoin('c.products', 'p')
                  ->addSelect('p')
                  ->andWhere('p.provider = :provider')
                  ->setParameter('provider', $provider)
                  ->addOrderBy('c.name')
                  ->getQuery()
                  ->getResult();
    }
}

但是，尽管提供者拥有许多产品，但我总是有一个空洞的结果。请我应该如何实现此查询。谢谢

Doctrine2 / Symfony4：具有嵌套的ManyToOne关系的ManyToMany关系

0 个答案: