Spring 数据 jpa @Onetomany 问题

Question

@Entity
class Hospital{

@Id     
@GeneratedValue 
Private long hospitalId

Private String name;

Private string password;

@Embaded
Private Address address;

@Onetomany(mappedby=Hospital)
Private List<Department> department;

}

@Entity
class Department {

@Id     
@GeneratedValue 

private Long depId;

Private String department;

@Manytoone

@JoinColumn(name="hospitalId")

Private Hospital hospital

}

这里的场景就像第一个医院注册名称、密码、地址，只有在登录后医院才会输入部门详细信息。 我只想在医院获取注册并从特定医院获取部门的详细信息时将外键插入部门实体我想使用外键更新部门实体如何使用 spring 数据 jpa 实现它

Answer 1

尝试添加级联

@OneToMany(mappedBy = "class", cascade = [CascadeType.ALL])

Cascade 帮助您使用实体外键插入和更新，cascade 类型有一个不同的值：

• 全部
• 坚持
• 合并
• 消除
• 刷新
• 分离

参考Baeldung以了解所有案例及其目的。

我希望这会有所帮助。

Answer 2

我想这就是你要找的。

@Entity
@Table(name = "Hospital")
class Hospital{

    @Id
    @GeneratedValue
    Private long hospitalId

    Private String name;

    Private string password;

    @Embedded
    Private Address address;

    @OneToMany(mappedBy = "hospital", fetch = FetchType.LAZY)
    @JsonIgnore
    Private List<Department> department;

}

@Entity
@Table(name = "Department")
class Department {

    @Id
    @GeneratedValue
    private Long depId;

    Private String department;


    @JoinColumn(name = "hospitalId")
    @ManyToOne()
    @OnDelete(action = OnDeleteAction.CASCADE)
    Private Hospital hospital;

}