如何准确地使用 onDelete = “SET NULL"?- 教义2 [英] How exactly to use onDelete = "SET NULL" - Doctrine2

问题描述

我有一个 Category 类包含这个:

I have a class Category containing this:

/**
 * @ORMOneToMany(targetEntity="Friend", mappedBy="category")
 * @ORMOrderBy({"name" = "ASC"})
 */
protected $friends;

和一个班级朋友:

 /**
 * @ORMManyToOne(targetEntity="Category", inversedBy="friends")
 * @ORMJoinColumn(name="category_id", referencedColumnName="id",  onDelete="SET NULL")
 */
protected $category;

我想要的是能够删除类别，无论这个类别是否有一些朋友，如果有 - 这个朋友的类别字段设置为NULL.

What I want is to be able to delete categories no matter if there are some friends from this category, and if there are - the category field for this friends to be set to NULL.

我尝试将 onDelete="CASCADE" 放入 ManyToOne 注释，然后放入 OneToMany，我尝试了上面显示的内容，我尝试使用 cascade={"remove"} 在 OneToMany 注释中，但没有任何效果！我也找不到例子.你能帮我吗?

I tried to put onDelete="CASCADE" to the ManyToOne annotation, then to the OneToMany, I tried what is shown above, I tried using cascade={"remove"} in the OneToMany annotation, and nothing worked! I couldn't find a example as well. Could you please help me?

推荐答案

这一定是一个疯狂的答案，但您是否更新了数据库架构?onDelete="SET NULL" 在数据库级别，它必须在 innoDB 上工作.

This must be a crazy answer but did you update database schema? onDelete="SET NULL" is on database level, it must work on innoDB.

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