不得删除或更新母行:外国关键制约因素失败。
class Teacher {
/**
*@ORMOneToMany(targetEntity="publication", mappedBy="teacher")
*/
protected $publications;
}
class Publication {
/**
* @ORMManyToOne(targetEntity="Teacher", inversedBy="publications")
* @ORMJoinColumn(name="teacher_id", referencedColumnName="id")
*/
protected $teacher;
}
我想做的是,当你删除一名教师时,将教师转至全国扫盲委员会。 我想保留这一出版物,但没有提到教授。
我不知道在理论中如何能够做到这一点? 或者总是与教师的关系?
请在贵实体的说明中添加<代码>onDelete=”SET NUL"。 出版:
class Publication
{
/**
* @ORMManyToOne(targetEntity="Teacher", inversedBy="publications")
* @ORMJoinColumn(name="teacher_id", referencedColumnName="id", onDelete="SET NULL")
*/
protected $teacher;
}
这一修改在表态中进行了登记。 因此,您需要一个数据库迁移,或为此进行图形改动。
第6类
#[ORMJoinColumn(nullable: true, onDelete: SET NULL )]
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