entityManager.merge does not work in some cases

[alomine]

Describe the bug

Hello!
In some cases hibernate entityManager.merge fails to update some fields when setting them to null. I have prepared some test cases to show when it works just fine and when it fails. Fails are when database fields are null except the one that needs to be set to null AND its not date field (which somehow works).

Case might be similar to:
#22080
and
#2815

Also if something is not clear or i need to provide more info, please feel free to ask

Expected behavior

All tests in given repository should pass

Actual behavior

2 of 6 tests fails. You can see in logs that update is not made

How to Reproduce?

Simply use .\mvnw test in my project

Output of uname -a or ver

Output of java -version

17

Quarkus version or git rev

3.7.2

Build tool (ie. output of mvnw --version or gradlew --version)

mvnw

Additional information

No response

[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

[alomine]

Is there a way to disable hibernate bytecode enhancement on quarkus ?

[yrodiere]

There is not, and there are no plans to allow it.