Cascading save/persist not working with @OneToOne

Persisting an entity that contains a @OneToOne relationship to a child entity should generate insert statements for both the parent and child entities.

Task List

• Steps to reproduce provided
• Stacktrace (if present) provided
• Example that reproduces the problem uploaded to Github
• Full description of the issue provided (see below)

Steps to Reproduce

1. Define the entities and repositories

@Entity
public class Face {
    @GeneratedValue
    @Id
    private Long id;

   @OneToOne(cascade = CascadeType.PERSIST)
   private Nose nose;
  
   // Getters, setters
}

@Entity
public class Nose {
    @GeneratedValue
    @Id
    private Long id;
  
   // Getters, setters
}

public interface FaceRepository extends CrudRepository<Face, Long> { }

public interface NoseRepository extends CrudRepository<Face, Long> { }

1. Create and save entities

Face face = new Face("Bob");
Nose nose = new Nose();
face.setNose(nose);

Face savedFace = faceRepository.save(face);
assertNotNull(savedFace.nose);

Expected Behaviour

The child entity should be saved.

Actual Behaviour

The child entity is not saved.

Environment Information

• Operating System: NixOS 20.03
• Micronaut Version: 2.1.3
• JDK Version: 14

Example Application

I added a test case displaying this issue:

https://github.com/matt-snider/micronaut-data/commit/b4dc0a9027d55f55a890dadcf696af718e9a9ae2

[nhoughto]

I had this but stepping through the micronaut data code, I hit this condition https://github.com/micronaut-projects/micronaut-data/blob/2.1.x/data-jdbc/src/main/java/io/micronaut/data/jdbc/operations/DefaultJdbcRepositoryOperations.java#L735

where it uses the id to check if it should insert it or not (which makes sense since no lazy loading/proxy objs), so cascading inserts only works in a world where ids are generated in some way, and not setup by the DAO/some other code itself it seems?

[issmo]

@matt-snider I am unable to reproduce the issue as you described it.

However, from the test case you produced, the issue is not in the save method which looks to work correctly. The issue is that findById does not do a Join automatically to retrieve the entity. I think that this is by design as data-jdbc is not an ORM.

You can instruct micronaut data to do a join by decorating the findById method with @Join(“nose”). This should work