inversedBy 和mappedBy 有什么区别?

What is the difference between inversedBy and mappedBy?(inversedBy 和mappedBy 有什么区别?)

问题描述

我正在使用 Zend Framework 2 和 Doctrine 2 开发我的应用程序.

I am developing my application using Zend Framework 2 and Doctrine 2.

在写注解时，我无法理解 mappedBy 和 inversedBy 之间的区别.

While writting annotations, I am unable to understand the difference between mappedBy and inversedBy.

我应该什么时候使用mappedBy?

我应该什么时候使用inversedBy?

我什么时候不应该使用?

When should I use neither?

这是一个例子:

 /**
 *
 * @ORMOneToOne(targetEntity="custModEntityPerson", mappedBy="customer")
 * @ORMJoinColumn(name="personID", referencedColumnName="id")
 */
protected $person;

/**
 *
 * @ORMOneToOne(targetEntity="AuthEntityUser")
 * @ORMJoinColumn(name="userID", referencedColumnName="id")
 */
protected $user;

/**
 *
 * @ORMManyToOne (targetEntity="custModEntityCompany", inversedBy="customer")
 * @ORMJoinColumn (name="companyID", referencedColumnName="id")
 */
protected $company;

我进行了快速搜索并找到了以下内容，但我仍然感到困惑:

I did a quick search and found the following, but I am still confused:

• 示例 1
• 示例 2
• 示例 3

推荐答案

• ma​​ppedBy 必须在(双向)关联的反面指定
• inversedBy 必须在(双向)关联的拥有方指定
• mappedBy has to be specified on the inversed side of a (bidirectional) association
• inversedBy has to be specified on the owning side of a (bidirectional) association

来自教义文档:

• ManyToOne 始终是双向关联的拥有方.
• OneToMany 始终是双向关联的反面.
• OneToOne 关联的拥有方是包含外键的表的实体.

参见 https://www.doctrine-project.org/projects/doctrine-orm/en/latest/reference/unitofwork-associations.html

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