休眠复合外键和单个表中的主键的一对一映射 [英] Hibernate one to one mapping on composite foreign key and primary key in single table

问题描述

我有一个Catagory表，带有复合主键和外键。我的表结构就像

  CREATE TABLE CATAGORY（
 CATAGORY_ID int（11）NOT NULL，
 CATAGORY_NAME varchar（50）DEFAULT NULL，
 VERSION int（11）NOT NULL，
 PARENT_ID int（11）DEFAULT NULL，
 PRIMARY KEY（CATAGORY_ID，VERSION）
）; 
 
 ALTER TABLE CATAGORY ADD CONSTRAINT FOREIGN KEY（PARENT_ID，VERSION）REFERENCES CATAGORY（CATAGORY_ID，VERSION）; 
  

我想要一个像这样的Catagory类的ORM映射

  public class Catagory {
 @EmbeddedId 
 private CatagoryPk pk; 
 @Column（name =CATAGORY_NAME）
 private String catagoryName; 
 
私人类别parentId; 
 
私人清单< Catagory>孩子; 
 
 
 @Embeddable 
 public class CatagoryPk {
 @Column（name =VERSION）
 private Integer version; 
 @Column（name =CATEGORY_ID）
 private Integer catagoryId; 
} 
  

现在如何注释

 私人类别parentId; 
私人列表< Catagory>孩子; 
  

解决方案

  @JoinColumns （{
 @JoinColumn（name =VERSION，referencedColumnName =VERSION），
 @JoinColumn（name =PARENT_ID，referencedColumnName =CATAGORY_ID）
}）
 @ManyToOne 
私人类别parentId; 
 
 @OneToMany（mappedBy =parentId）
私人列表< Catagory>孩子的; 
  

或带有 @IdClass 的版本，而不是 @EmbeddableId （用Eclipselink 2.2.1测试）：

pre $ public class CatagoryPk实现Serializable {

私有Integer版本;
private Integer catagoryId;
$ b $ public CatagoryPk（）{
}

public CatagoryPk（Integer version，Integer catagoryId）{
this.version = version;
this.catagoryId = catagoryId;



@Entity
@IdClass（CatagoryPk.class）
public class Catagory {
@Column（name =VERSION ）
@Id私人整数版本;
@Column（name =CATAGORY_ID）
@Id private Integer catagoryId;
$ b @ManyToOne
@JoinColumns（{
@JoinColumn（name =VERSION，referencedColumnName =VERSION，insertable = false，updatable = false），
@JoinColumn（name =PARENT_ID，referencedColumnName =CATAGORY_ID）
}）
private类别parentId;
}


I have a Catagory table, with composite primary key and foreign key. My table structure is like

CREATE TABLE CATAGORY (
  CATAGORY_ID int(11) NOT NULL,
  CATAGORY_NAME varchar(50) DEFAULT NULL,
  VERSION int(11) NOT NULL,
  PARENT_ID  int(11) DEFAULT NULL,
  PRIMARY KEY (CATAGORY_ID,VERSION)
);

ALTER TABLE CATAGORY ADD CONSTRAINT FOREIGN KEY (PARENT_ID, VERSION) REFERENCES CATAGORY (CATAGORY_ID, VERSION); 

and I want a ORM mapping with Catagory class like this

public class Catagory {
    @EmbeddedId
    private CatagoryPk pk ;
    @Column(name="CATAGORY_NAME")
    private String  catagoryName;

    private Catagory parentId;

    private List<Catagory> childs ;                 

}
@Embeddable
public class CatagoryPk {
    @Column(name="VERSION")
    private Integer version;
    @Column(name="CATEGORY_ID")
    private Integer catagoryId;
}

Now how to annotate

private Catagory parentId;  
private List<Catagory> childs ;  

解决方案

@JoinColumns({
    @JoinColumn(name="VERSION", referencedColumnName="VERSION"),
    @JoinColumn(name="PARENT_ID", referencedColumnName="CATAGORY_ID")
})
@ManyToOne
private Catagory parentId;

@OneToMany(mappedBy="parentId")
private List<Catagory> childs;  

or version with @IdClass instead of @EmbeddableId (tested with Eclipselink 2.2.1):

public class CatagoryPk implements Serializable {

    private Integer version;
    private Integer catagoryId;

    public CatagoryPk() {
    }

    public CatagoryPk(Integer version, Integer catagoryId) {
        this.version = version;
        this.catagoryId = catagoryId;
    }
}

@Entity
@IdClass(CatagoryPk.class)
public class Catagory {
    @Column(name="VERSION")
    @Id private Integer version;
    @Column(name="CATAGORY_ID")
    @Id private Integer catagoryId;

    @ManyToOne
    @JoinColumns({
        @JoinColumn(name="VERSION", referencedColumnName="VERSION", insertable=false, updatable=false),
        @JoinColumn(name="PARENT_ID", referencedColumnName="CATAGORY_ID")
    })
    private Catagory parentId;
}

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