Question

我有以下关系：

@OneToMany(fetch = FetchType.EAGER, mappedBy="note", cascade = CascadeType.REMOVE, orphanRemoval = true)
private Set<Review> reviews = new HashSet<>();

在 Note.java 和

中

@OneToMany(fetch = FetchType.EAGER, mappedBy = "expert", cascade = CascadeType.ALL, orphanRemoval = true)
private Set<Review> notes = new HashSet<>();

在 Expert.java 中。

如您所见，它们引用Review类，它表示Note和Expert之间的M对N关系。当我需要为该关系添加额外的属性时，我创建了一个ReviewId类和一个Review类，如下所示：

@Embeddable
public class ReviewId implements Serializable {

    @Column(name = "fk_note")
    protected Long noteId;

    @Column(name = "fk_expert")
    protected Long expertId;

    [...]
}

@Entity
public class Review {
    @EmbeddedId
    private ReviewId id;

    private int value;

    private String comment;

    @ManyToOne
    @JoinColumn(name = "fk_note", insertable = false, updatable = false)
    private Note note;

    @ManyToOne
    @JoinColumn(name = "fk_expert", insertable = false, updatable = false)
    private Expert expert;

    [...]
}

当我尝试删除出现在这种关系中的注释或专家时，出现以下错误：

Cannot delete or update a parent row: a foreign key constraint fails (`db_example`.`review`, CONSTRAINT `FKls65s9wl28v98ts2kifir37p7` FOREIGN KEY (`fk_note`) REFERENCES `note` (`id`))

我如何使Hibernate删除与某个注释/专家相关的所有评论？谢谢！

Answer 1

这可以通过FluentJPA完成：

long noteId; //passed as a parameter

FluentQuery query = FluentJPA.SQL((Review review) -> {

    DELETE().FROM(review);
    WHERE(review.getId().getNoteId() == noteId);
});

...
query.createQuery(em).executeUpdate();

Hibernate：如何删除具有额外属性的多对多关系中的实体

1 个答案: