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Java @@embeddedId部分上的OneToMany实体映射_Java_Spring - Fatal编程技术网

Java @@embeddedId部分上的OneToMany实体映射

Java @@embeddedId部分上的OneToMany实体映射,java,spring,Java,Spring,我目前正试图用一个复合键从表中提取一组实体,但我只想用id_a执行连接以获得一个集合,而不是同时得到两个(id_a和id_b),这将产生一个结果 这不是原始代码,但它是我试图实现的一个示例 @Entity public class ItemA { @EmbeddedId private ItemId itemId; @OneToMany private Set<ItemB> itemsB = new HashSet<>(); } @Embeddab

我目前正试图用一个复合键从表中提取一组实体,但我只想用id_a执行连接以获得一个集合,而不是同时得到两个(id_a和id_b),这将产生一个结果

这不是原始代码,但它是我试图实现的一个示例

@Entity
public class ItemA {

  @EmbeddedId
  private ItemId itemId;

  @OneToMany
  private Set<ItemB> itemsB = new HashSet<>();

}

@Embeddable
public class ItemID implements Serializable {
  
  private Integer itemIDA;
  private Integer itemIDB;

}

@Entity
public class ItemB {

  @Id
  private Integer itemIDA;

}

这就是你想要达到的目标吗不,在您提到的链接中,op想要查询实体,我正在尝试连接表,但只使用组合键的一部分
@OneToMany
@JoinTable(
    name = "itemB",
    joinColumns = { @JoinColumn(name = "itemIDA") },
    inverseJoinColumns = { @JoinColumn(name = "itemIDA") }
)
    private Set<ItemB> detalleUsuarios = new HashSet<>();
@OneToMany
@JoinTable(
    name = "itemB",
    joinColumns = { @JoinColumn(name = "itemID.itemIDA") },
    inverseJoinColumns = { @JoinColumn(name = "itemIDA") }
)
    private Set<ItemB> detalleUsuarios = new HashSet<>();
A Foreign key refering com.example.ItemA from com.example.ItemB has the wrong number of column. should be 2