java - Hibernate hsql 删除的 MySQLIntegrityConstraintViolationException。无法删除或更新父行

Question

我有家长 Filter实体和一个方向List<Ad>ads作为 @OneToMany 的 child 关系。我尝试使用 Hibernate hql 删除超过一周的广告查询但得到:

com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Cannot delete or update a parent row: a foreign key constraint fails (gecars.filters_ads, CONSTRAINT FK_gcri6h0918u8o2ybd6yfquk79 FOREIGN KEY (ads_id) REFERENCES ads (id))

用户:

@Entity
@Table(name="users")
public class User {
 ...
 @OneToMany(fetch = FetchType.LAZY, cascade=CascadeType.ALL, mappedBy="user") 
 @OrderBy("id")
 private Set<Filter> filters = new HashSet<Filter>(0);
 ...

过滤器:

@Entity
@Table(name="filters")
public class Filter {
  ...
  // I also tried use @OneToMany(CascadeType.REMOVE, orphanremoval=true)
  // or @OneToMany(cascade=CascadeType.ALL,orphanRemoval=true)
  @OneToMany 
  private Set<Ad> ads; 
  ...

广告:

@Entity
@Table(name="ads")
public class Ad {
 ...
 private Date insertTime = new Date();
 ...

DAO删除方法:

public void deleteOldAds(Date date){
    String hql = "delete from Ad where insertTime < :date";
    session.createQuery(hql).setParameter("date",  date).executeUpdate();
}

Answer 1

问题的原因是，如果 @OneToMany 关联方是关系的所有者，则使用联接表。

要指定使用 ads 表中的联接列(外键)而不是单独的联接表进行关联，只需将关联映射到 @JoinColumn:

@OneToMany
@JoinColumn 
private Set<Ad> ads;