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Java Can';不要建立一种多对多的关系_Java_Hibernate_Jpa_Many To Many - Fatal编程技术网

Java Can';不要建立一种多对多的关系

Java Can';不要建立一种多对多的关系,java,hibernate,jpa,many-to-many,Java,Hibernate,Jpa,Many To Many,有两个实体:InventoryList和Parameter @Data @NoArgsConstructor @EqualsAndHashCode(callSuper = true) @Entity @Table(name = "parameters") public class ParameterEntity extends Parameter { @ManyToMany(mappedBy = "parameters") private Set<

有两个实体:InventoryList和Parameter

@Data
@NoArgsConstructor
@EqualsAndHashCode(callSuper = true)
@Entity
@Table(name = "parameters")
public class ParameterEntity extends Parameter {

@ManyToMany(mappedBy = "parameters")
private Set<UUID> inventoryLists;


}

@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@EqualsAndHashCode(callSuper = true)
name = "lists"
public class InventoryListEntity extends InventoryList {

@ManyToMany(cascade = CascadeType.PERSIST)
@JoinTable(
    name = "list_parameters",
    joinColumns = @JoinColumn(name = "il_id"),
    inverseJoinColumns = @JoinColumn(name = "parameter_id")
)
private Set<UUID> parameters;

}
但出于性能方面的原因,我必须完成这项任务

在这种情况下有什么解决方案

  • 关联中集合中的项只能是其他实体。因此,在这种情况下,您只能有如下内容:
  • @实体
    @表(name=“parameters”)
    公共类参数扩展参数{
    @多个(mappedBy=“参数”)
    私有集合清单;
    }
    @实体
    @表(name=“列表”)
    公共类InventoryListenty扩展了InventoryList{
    @ManyToMany(cascade=CascadeType.PERSIST)
    @可接合(
    name=“列出参数”,
    joinColumns=@JoinColumn(name=“il_id”),
    inverseJoinColumns=@JoinColumn(name=“parameter\u id”)
    )
    私有设置参数;
    }
    
  • 如果要在集合中使用值或可嵌入类型,则应使用注释。但您应该记住,值类型集合的生命周期完全由其所属实体控制。因此,在这种情况下,不可能有双向关系
  •  Many To Many attribute value type should not be UUID