Thanks for the help guys... I managed to do it by (sort of ) combining both pieces of advice and I altered the Foreign Key so that it would CASCADE on DELETE.
Hibernate: Cannot Delete Object - foreign key constraint - CascadeType.REMOVE
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16-07-2023 - |
Question
I have two persistable entities Obj1 and Obj2. Obj2 contains a reference to Obj like below. There is no reference (at code level - Java) to Obj2 in Obj1.
public class Obj2{
....
@ManyToOne(cascade = {CascadeType.PERSIST, CascadeType.MERGE, CascadeType.REFRESH, CascadeType.REMOVE}, optional = true)
private Obj1 obj1;
I updated Ojbj 1 with @OneToMany as suggested:
public class Obj1{
....
@OneToMany(cascade = {CascadeType.PERSIST, CascadeType.MERGE, CascadeType.REFRESH, CascadeType.REMOVE,CascadeType.ALL},orphanRemoval = true)
private List<Obj2> obj2;
When I try to delete Obj1:
em.remove(obj1Instance)
It fails due to Foreigh Key constaint
00:35:23,109 WARN [com.arjuna.ats.arjuna] (http--127.0.0.1-8080-1) ARJUNA012125: TwoPhaseCoordinator.beforeCompletion - failed for SynchronizationImple< 0:ffff7f000101:-7f20c644:5369716f:26, org.hibernate.engine.transaction.synchronization.internal.RegisteredSynchronization@dcedf7 >: javax.persistence.PersistenceException: org.hibernate.exception.ConstraintViolationException: Cannot delete or update a parent row: a foreign key constraint fails (`my_db`.`obj2`, CONSTRAINT `FKC4783505BB5D6339` FOREIGN KEY (`obj1_pk`) REFERENCES `obj1` (`pk`))
...
... 94 more
Caused by: org.hibernate.exception.ConstraintViolationException: Cannot delete or update a parent row: a foreign key constraint fails (`my_db`.`obj2`, CONSTRAINT `FKC4783505BB5D6339` FOREIGN KEY (`obj1_pk`) REFERENCES `obj1` (`pk`))
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Cannot delete or update a parent row: a foreign key constraint fails (`my_db`.`obj2`, CONSTRAINT `FKC4783505BB5D6339` FOREIGN KEY (`obj1_pk`) REFERENCES `obj1` (`pk`))
I had (wrongly it seems!) asumed that CascadeType.REMOVE would take care of this? How should I handle this delete?
/T
La solution 2
Autres conseils
Either handle it manually or add a reverse relationship @OneToMany(orphanRemoval=true)
in Obj1.
When did you add optional = true
? Is it before deploying the application or after? If it is after, MySQL wouldn't update the NotNull constraint on my_db
.obj2
, check if column
is Nullable. If it is not, drop and add the constraint obj1_pk
FKC4783505BB5D6339
so it can be Nullable.
Or you can simply drop these two tables and recreate them.