Java 未在一对多关系中设置的关系

我使用Spring Boot 2，Spring数据与Hibernate实现。 使用的数据库是Postgres

我尝试将

CarServices

与其子项

carcomponentexecutions

：

@Entity
public class CarServices{

    @OneToMany(mappedBy = "carService", cascade = CascadeType.PERSIST)
    private List<CarComponentOccurrences> carComponentOccurrences;

}


@Entity
public class CarComponentOccurrences {
    ...
    @ManyToOne
    private CarComponents carComponent;

    @ManyToOne
    private CarServices carService;

}

编辑2

CREATE TABLE car_component_occurrences
(
  id integer NOT NULL,
  ...
  car_component_id integer,
  car_service_id integer,
  CONSTRAINT car_component_occurrences_pkey PRIMARY KEY (id),
  CONSTRAINT fka4fmpytg0s9a94377pdw5ssib FOREIGN KEY (car_service_id)
      REFERENCES car_services (id) MATCH SIMPLE
      ON UPDATE NO ACTION ON DELETE NO ACTION,
  CONSTRAINT fko85tjs5s6f1o9u7kkk152d147 FOREIGN KEY (car_component_id)
      REFERENCES car_components (id) MATCH SIMPLE
      ON UPDATE NO ACTION ON DELETE NO ACTION
)

编辑3

Hibernate: 
    select
        nextval ('public.car_component_occurrences_id_seq')
Hibernate: 
    insert 
    into
        public.car_component_occurrences
        ( car_component_id, car_service_id, name, id) 
    values
        (?, ?, ?, ?)
Hibernate: 
    update
        public.car_services 
    set
        name=?,
    where
        id=?

---

如果数据库中的列名是

car\u component\u id

和

car\u service\u id

，则应使用

@JoinColumn

注释来覆盖持久性提供程序的默认值，该持久性提供程序应为：

carcomponent\u id

和

carservice\u id

（如果这些引用实体的主键分别命名为

id

）

参考资料来源：

默认值（仅在使用单个联接列时适用）： 下列内容的串联：引用的名称 引用实体或可嵌入实体的关系属性或字段 类；引用的主键列的名称

尝试：

在

CarServices

中：

@Entity
public class CarServices{

    @OneToMany(mappedBy = "carService", cascade = CascadeType.PERSIST)
    private List<CarComponentOccurrences> carComponentOccurrences;

}


@Entity
public class CarComponentOccurrences {
    ...
    @ManyToOne
    private CarComponents carComponent;

    @ManyToOne
    private CarServices carService;

}

• cascade=CascadeType.PERSIST->PERSIST，MERGE

在

carcomponentoccurrencess

中：

@Entity
public class CarServices{

    @OneToMany(mappedBy = "carService", cascade = CascadeType.PERSIST)
    private List<CarComponentOccurrences> carComponentOccurrences;

}


@Entity
public class CarComponentOccurrences {
    ...
    @ManyToOne
    private CarComponents carComponent;

    @ManyToOne
    private CarServices carService;

}

• @ManyToOne私有CarComponents carComponent；->@ManyToOne（cascade=CascadeType.PERSIST）

---

让我知道这是否有帮助。

尝试添加设置和保存实体的整个方法OK我更新了帖子所以在会话或EntityManager等上调用了实际的保存/持久化在哪里。我添加了保存代码我使用spring security save…所以只有外键没有设置？CarService是否已执行？完成了此修改但没有任何变化，这是同一个问题。原因如下：您持久化了一个CarServices。现在，为了让Hibernate级联任何持久化操作，必须使用一个不间断的对象链进行注释，即CarServices->CarComponentInstances->CarComponents。缺少@ManyTone上的级联会导致CarComponents无法持久化。根据我的经验，Persist-chain和Persist-only通常不适用于集合，尽管很奇怪CarService在这种情况下没有得到持久化。