How to manually start a transaction on a shared EntityManager in Spring?

Question

I have a LocalContainerEntityManagerFactoryBean as EntityManager instance.

To quickly drop a full tables\' content, I want to run the follo

Answer 1

@Transactional annotation should not be applied on Dao method but on a service method. Although your code says DatabaseService is a service, but by inserting EntityManger inside a service does not make any sense.

Correct way to implement is to create a Dao like below.

@Repository
public class DatabaseDao {
    @PersistenceContext
    private EntityManager em;

    public void clear() {
        em.createNativeQuery("TRUNCATE TABLE MyTable").executeUpdate();
    }
}

Then call the dao method from a service method with @Transactional annotation.

@Service
public class DatabaseService {
    @Autowired
    private DatabaseDao dao;

    @Transactional
    public void clear() {
        dao.clear();
    }
}

Also, add @EnableTransactionManagement in your Configuration class