Hibernate delete from onetomany

问题

I have two tables with OneToMany relation

class ServiceProvider {

...

@OneToMany(fetch=FetchType.EAGER,mappedBy="serviceProvider", cascade={CascadeType.ALL,CascadeType.REMOVE},orphanRemoval = true) @OnDelete(action=OnDeleteAction.CASCADE) private List serviceCenters; ...

}

class ServiceCenterDetails {

... //bi-directional many-to-one association to ServiceProviderDomainMap @ManyToOne @JoinColumn(name="SERVICE_PROVIDER_ID") private ServiceProvider serviceProvider;

...

}

I am trying to delete provide row. But i am getting below error:

Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Cannot delete or update a parent row: a foreign key constraint fails (fixoline.service_center_details, CONSTRAINT FK_qvahoxeovx9vmwl6mcu2c0lyw FOREIGN KEY (SERVICE_PROVIDER_ID) REFERENCES service_provider (ID))

below is the way i am trying

  String hql = "DELETE FROM ServiceProvider WHERE id =  :providerId";
  Query query = sessionFactory.getCurrentSession().createQuery(hql);
          query.setParameter("providerId",providerId);

  int result = query.executeUpdate();

could someone pls help resolving it?

回答1:

The error message is quite clear: There are foreign key references to the ServiceProviders you are trying to delete. Delete ServiceCenterDetails first:

delete from ServiceCenterDetails where serviceProvider.id = :providerId

回答2:

There are two tings,

1. Why you are using @OnDelete when you using CascadeType.ALL in @oneToMany? CascadeType.ALL will delete child entities when parent is deleted.

2. @OnDelete mainly used in child entities with @ManyToOne not otherwise.

Try with any option and check.

回答3:

Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Cannot delete or update a parent row: a foreign key constraint fails

this exception tells that you should delete your ServiceCenterDetails associated with ServiceProviders first and then delete the ServiceProviders.

来源：https://stackoverflow.com/questions/34831438/hibernate-delete-from-onetomany