Hibernate session not recognizing detached entities after merge operation
I'm optimizing some code but Quick question that's been bugging me - I'm working with an scenario with Hibernate where detached entities are not being recognized after I perform a merge operation, leading to unexpected results... I have a basic setup using Hibernate 5.4.32 and Spring Boot 2.4.3. I start by retrieving an entity from the database, then I detach it by closing the session. Later, I modify some properties of this entity and attempt to merge it back into the session, but the changes are not persisted as expected. Here’s a simplified version of my code: ```java @Entity public class User { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) private Long id; private String name; private String email; // Getters and setters } @Autowired private EntityManager entityManager; public void updateUser(Long userId, String newName) { // Retrieve the user, which makes it managed User user = entityManager.find(User.class, userId); // Detaching by closing the session entityManager.close(); // Modify the detached entity user.setName(newName); // Start a new session and merge entityManager = entityManagerFactory.createEntityManager(); entityManager.getTransaction().begin(); entityManager.merge(user); entityManager.getTransaction().commit(); } ``` After the merge, I expected the user’s name to be updated in the database, but it remains unchanged. When I debug the application, I see that the `merge` method returns the entity, but the name attribute isn’t updated in the database. I’ve also tried calling `entityManager.flush()` right after the merge, but that doesn’t seem to help either. Could I be missing something in my approach or configuration that prevents the changes from being persisted properly? Any insights or recommendations would be greatly appreciated! Am I missing something obvious? This issue appeared after updating to Java latest. For reference, this is a production service.