KafkaDualWriteProblem.java

@Service
public class DataService {

    @Autowired
    private DatabaseRepository databaseRepository;

    @Autowired
    private KafkaTemplate<String, String> kafkaTemplate;

    @Transactional
    public void updateDataAndPublishEvent(String data) {
        databaseRepository.save(new DataEntity(data)); // Database operation
        kafkaTemplate.send("topicName", "Data updated event"); // Kafka event publishing
        // The above operations are not atomically consistent, risking data inconsistency.
    }
}