如何删除具有两个关系的“反向实体”

Question

销售，库存和目录之间存在双向关系。销售和库存应该有一个商品。但目前情况并非总是如此......所以关系是“可空的”。

class Sale {

    /**
     * @ORM\ManyToOne(targetEntity="App\Entity\Stock", inversedBy="sales")
     */
    private $stock;

    public function getCatalog(): ?Catalog
    {
        return $this->catalog;
    }

    public function setCatalog(?Catalog $catalog): self
    {
        $this->catalog = $catalog;

        return $this;
    }
}

class Stock
{
    /**
     * @ORM\OneToOne(targetEntity="App\Entity\Catalog", inversedBy="stock")
     */
    private $catalog;

    public function getCatalog(): ?Catalog
    {
        return $this->catalog;
    }

    public function setCatalog(?Catalog $catalog): self
    {
        $this->catalog = $catalog;

        return $this;
    }
}

class Catalog
{
    /**
     * @ORM\OneToMany(targetEntity="App\Entity\Sale", mappedBy="catalog")
     */
    private $sales;

    /**
     * @ORM\OneToOne(targetEntity="App\Entity\Stock", mappedBy="catalog")
     */
    private $stock;

    public function addSale(Sale $sale): self
    {
        if (!$this->sales->contains($sale)) {
            $this->sales[] = $sale;
            $sale->setCatalog($this);
        }

        return $this;
    }

    public function removeSale(Sale $sale): self
    {
        if ($this->sales->contains($sale)) {
            $this->sales->removeElement($sale);
            // set the owning side to null (unless already changed)
            if ($sale->getCatalog() === $this) {
                $sale->setCatalog(null);
            }
        }

        return $this;
    }

    public function getStock(): ?Stock
    {
        return $this->stock;
    }

    public function setStock(?Stock $stock): self
    {
        $this->stock = $stock;

        // set (or unset) the owning side of the relation if necessary
        $newCatalog = $stock === null ? null : $this;
        if ($newCatalog !== $stock->getCatalog()) {
            $stock->setCatalog($newCatalog);
        }

        return $this;
    }
}

所有这些都是在Symfony中使用make：entity自动生成的。组织目录时，还需要删除目录条目。

class CatalogController extends AbstractController 
{

    /**
     * @Route(
     *     path    = "/catalog-delete/{id<[1-9]\d*>}",
     *     name    = "catalog_delete",
     *     methods = {"GET"}
     * )
     */
    public function delete(int $id)
    {
        // get catalog
        $catalog = $this->catalogRepository->find($id);
        if (!$catalog) {
            throw $this->createNotFoundException($this->translator->trans('system.error.notfound') . $id);
        }

        // delete
        $this->entityManager->remove($catalog);
        $this->entityManager->flush();

        return $this->redirectToRoute('catalog_list');
    }
}

到目前为止很简单。但是如何在不删除任何股票或销售的情况下删除关联？我确实得到这样的错误（没有删除关联）

Cannot delete or update a parent row: a foreign key constraint fails (`symfony`.`sale`, CONSTRAINT `FK_E54BC005DCD6110` FOREIGN KEY (`stock_id`) REFERENCES `stock` (`id`))

或者喜欢

Call to a member function getCatalog() on null

当我尝试里面的函数delete（）;）

$catalog->setStock(null);
foreach($catalog->getSales() as $sale) {
    $catalog->getSales()->removeElement($sale); // ????????
}

我可以使用DQL将Sales和Stock中的category_id设置为null（UPDATE sale / stock SET category_id = null WHERE category_id = X）。但我认为这不是常见的'orm方式'。

对于这种情况，自动生成的函数对我来说有点奇怪。此处的学说文档qazxsw poi

我曾经读过，只有拥有方负责协会，但我如何进入我的职能股票和所有销售，如果有的话？

对不起，这是一个很长的问题和一个基本主题

谢谢您最好的问候

---

我的问题被标记为重复。主要区别在于

我想知道在我的问题中，如何实现函数调用以将所拥有的实体（两个或多个）设置为null。删除过程。哪个实体，什么样的电话。只添加

https://www.doctrine-project.org/projects/doctrine-orm/en/2.6/reference/working-with-associations.html#removing-associations

（旧答案）不解决问题。

--------- DQL替代方法----------

@ORM\JoinColumn(name="catalog_id", referencedColumnName="id", onDelete="SET NULL")  

我有史以来最长的职位;）

Answer 1

解决方案确实是这个简单的设置。它也可以是单向关系。

// Controller

/**
 * @Route(
 *     path    = "/catalog-delete/{id<[1-9]\d*>}",
 *     name    = "catalog_delete",
 *     methods = {"GET"}
 * )
 */
public function delete(int $id)
{
    // get catalog
    $numDeleted = $this->catalogRepository->delete($id);
    if (!$numDeleted) {
        throw $this->createNotFoundException($this->translator->trans('system.error.notfound') . $id);
    }

    return $this->redirectToRoute('catalog_list');
}

// Repository

/**
 * Delete with associations
 */
public function delete(int $id): int
{
    $this->getEntityManager()
        ->createQuery(/** @lang DQL */'
            UPDATE App\Entity\Sale s 
               SET s.catalog = NULL
             WHERE s.catalog = :id 
        ')
        ->setParameter('id', $id)
        ->execute()
    ;

    $this->getEntityManager()
        ->createQuery(/** @lang DQL */'
            UPDATE App\Entity\Stock s 
               SET s.catalog = NULL
             WHERE s.catalog = :id 
        ')
        ->setParameter('id', $id)
        ->execute()
    ;

    $numDeleted = $this->getEntityManager()
        ->createQuery(/** @lang DQL */'
            DELETE FROM App\Entity\Catalog c
                  WHERE c.id = :id 
        ')
        ->setParameter('id', $id)
        ->execute()
    ;

    return $numDeleted;
}

然后控制器功能很好用。昨天我尝试了太多东西......