entityManager.merge does not work in some cases about quarkus

[quarkus-bot]

/cc @gsmet (hibernate-orm), @yrodiere (hibernate-orm)

[yrodiere]

Hey @alomine, thanks for reporting.
Are you sure this is specific to Quarkus? Can you reproduce with plain Hibernate ORM test case templates?

[alomine]

Hello @yrodiere, thanks for response.
I'll try this. For now i can say two things - its not working in both quarkus 2.x.x version and 3.x.x (different hibernate versions) and its totally working on wildfly 26

[yrodiere]

Thanks, looking forward to the reproducer.

[alomine]

@yrodiere
I did two test cases with plain hibernate based on examples that you posted. Both 7/7 successful

[gsmet]

My guess is that it's related to the bytecode enhancement.

[Nikita-V0lkov]

I have some research on this issue.

1. Transactional annotation on the TestBugTest class instead of TestEntityService.

All tests will be passed, but the data in the database will not be updated.

---

2. QuarkusTransaction instead of annotation. You will have two possible variants:

2.1 Test fail, data not updated.

@Test
public void saveAndCheckWithNonNullNumber_test() {
    QuarkusTransaction.begin();
    testEntityService.clean();
    TestEntity testEntity = createEntityWithNonNullNumber();
    testEntityService.save(testEntity);
    QuarkusTransaction.commit();
    assertEquals(1, testEntityService.find(1L).getNumberField());
    
    QuarkusTransaction.begin();
    testEntity = createEntityWithAllNulls();
    testEntityService.update(testEntity);
    QuarkusTransaction.commit();
    assertEquals(null, testEntityService.find(1L).getNumberField());
}

2.2 Test passed, data not updated (similar to placing the Transactional annotation on the TestBugTest class).

@Test
public void saveAndCheckWithNonNullNumber_test() {
    QuarkusTransaction.begin();
    testEntityService.clean();
    TestEntity testEntity = createEntityWithNonNullNumber();
    testEntityService.save(testEntity);
    assertEquals(1, testEntityService.find(1L).getNumberField());
    QuarkusTransaction.commit();
    
    QuarkusTransaction.begin();
    testEntity = createEntityWithAllNulls();
    testEntityService.update(testEntity);
    assertEquals(null, testEntityService.find(1L).getNumberField());
    QuarkusTransaction.commit();
}

---

3. Update "refreshed" data after save (Transactional on TestEntityService).

3.1 Works as intended data in db updated.

@Test
public void saveAndCheckWithNonNullNumber_test() {
    testEntityService.clean();
    TestEntity testEntity = createEntityWithNonNullNumber();
    TestEntity savedEntity = testEntityService.save(testEntity);
    assertEquals(1, testEntityService.find(1L).getNumberField());
    
    savedEntity.setDateField(null);
    savedEntity.setNumberField(null);
    savedEntity.setStringField(null);
    testEntityService.update(savedEntity);
    assertEquals(null, testEntityService.find(1L).getNumberField());
}

public TestEntity save(TestEntity entity) {
    testEntityRepository.getEntityManager().persist(entity);
    testEntityRepository.getEntityManager().flush();
    testEntityRepository.getEntityManager().refresh(entity);
    return entity;
}

3.2 Save and find. Works similar to 3.1

@Test
public void saveAndCheckWithNonNullNumber_test() {
    testEntityService.clean();
    TestEntity testEntity = createEntityWithNonNullNumber();
    testEntityService.save(testEntity);
    assertEquals(1, testEntityService.find(1L).getNumberField());
    
    TestEntity savedEntity = testEntityService.find(1L);
    savedEntity.setDateField(null);
    savedEntity.setNumberField(null);
    savedEntity.setStringField(null);
    testEntityService.update(savedEntity);
    assertEquals(null, testEntityService.find(1L).getNumberField());
}

I hope this helps in some way.

[alomine]

Hello @Nikita-V0lkov,
in 3.1 and 3.2 entity you named as savedEntity is in persistent state and in this state this seems to be working. However by explicitly calling merge it shouldnt really matter.

[marko-bekhta]

Hey,

I did two test cases with plain hibernate based on examples that you posted. Both 7/7 successful

As Guillaume suggested, you'd need to add bytecode enhancement to reproduce the issue with Hibernate ORM only. Here's a bug report based on this in ORM's JIRA: https://hibernate.atlassian.net/browse/HHH-17761