我们可以扩展学说中的实体吗？ [英] Can we extend entities in Doctrine?

问题描述

我正在使用Doctrine进行我的第一个项目，结果迷迷糊糊。

I am working on my first project using Doctrine and I am stumbled on this.

1. 我有一个实体User，是映射的超类。

1. I have an entity User which is a mapped super class.

/**
 * @ORM\MappedSuperclass
 */
 abstract class User
 {
   /**
    * @var int
    */
   protected $id;

   /**
    * @var string
    */
   protected $name;

   /**
    * @ORM\Embedded(class="AppBundle\Entity\Person")
    * @var Person
    */
   protected $person;

   /**
    * @var Authors[]|Collection|Selectable
    */
   protected $authors;
 }

我创建了一个作者来自上述用户实体的实体

I create an author entity from the User entity above

    class Author extends User
    {
        /**
         * @ORM\Id
         * @ORM\Column(type="integer")
         * @ORM\GeneratedValue(strategy="AUTO")
         * @var int
         */
        protected $id;

        /**
         * @ORM\JoinColumn(name="publisher_id", referencedColumnName="id", nullable=false, unique=true)
         * @ORM\OneToOne(targetEntity="AppBundle\Entity\Publisher", inversedBy="book")
         * @var Publisher
         */
        protected $publisher;

        /**
         * @ORM\OneToMany(targetEntity="AppBundle\Entity\Publisher", mappedBy="author")
         * @var Approval[]|Collection|Selectable
         */
        protected $approvals;

    }

1. 我使用Author实体创建对象实体

1. I create an object entity Book using the Author entity

/**
 * @ORM\Entity
 * @ORM\Table(name="magazine", options={"collate":"utf8_general_ci"})
 */
class Book
{
   /**
    * @ORM\Id
    * @ORM\Column(type="integer")
    * @ORM\GeneratedValue(strategy="AUTO")
    * @var int
    */
   protected $id;

   /**
    * @ORM\JoinColumn(name="publisher_id", referencedColumnName="id", nullable=false, unique=true)
    * @ORM\OneToOne(targetEntity="AppBundle\Entity\Publisher", inversedBy="book")
    * @var Publisher
    */
   protected $publisher;
}

和我的发布商实体如下所示：

And my Publisher entity is as below:

    /**
     * @ORM\Entity
     * @ORM\Table(name="ops_approval", options={"collate":"utf8_general_ci"})
     */
    class Publisher
    {
       /**
        * @ORM\Id
        * @ORM\Column(type="integer")
        * @ORM\GeneratedValue(strategy="AUTO")
        * @var int
        */
       protected $id;

       /**
        * @ORM\Column(type="datetime", nullable=false)
        */
       protected $createdAt;

       /**
        * @ORM\ManyToOne(targetEntity="AppBundle\Entity\Author", inversedBy="authors")
        * @ORM\JoinColumn(name="author_id", referencedColumnName="id")
        */
       protected $author;

       /**
        * @ORM\OneToMany(targetEntity="AppBundle\Entity\Book", mappedBy="book"
        */
       protected $book;
    }

1. 现在，我可以扩展发布的实体来创建Book实体

1. Now, can I extend published entity to create a Book entity

/**
 * @ORM\Entity
 * @ORM\Table(name="book", options={"collate":"utf8_general_ci"})
 */
class Book extends Magazine
{
   /**
    * @ORM\Id
    * @ORM\Column(type="integer")
    * @ORM\GeneratedValue(strategy="AUTO")
    * @var int
    */
   protected $id;

   /**
    * @ORM\JoinColumn(name="published_id", referencedColumnName="id", nullable=false, unique=true)
     * @ORM\OneToOne(targetEntity="AppBundle\Entity\Publisher", inversedBy="book")
     * @var Publisher
     */
    protected $publisher;
}

推荐答案

U

如果需要，您还可以覆盖某些映射：

http://doctrine-orm.readthedocs.io/projects/ doctrine-orm / en / latest / tutorials / override-field-association-mappings-in-subclasses.html

You can also override some mappings if needed:
http://doctrine-orm.readthedocs.io/projects/doctrine-orm/en/latest/tutorials/override-field-association-mappings-in-subclasses.html

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