Spring:从具有关系的表中删除数据

CREATE TABLE User (
    id INT PRIMARY KEY,
    name VARCHAR(255)
);

CREATE TABLE Order (
    id INT PRIMARY KEY,
    user_id INT,
    amount DECIMAL(10, 2),
    FOREIGN KEY (user_id) REFERENCES User(id) ON DELETE CASCADE
);

@Entity
public class User {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String name;

    @OneToMany(mappedBy = "user", cascade = CascadeType.ALL, orphanRemoval = true)
    private List<Order> orders = new ArrayList<>();

    // getters and setters
}

@Entity
public class Order {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private BigDecimal amount;

    @ManyToOne
    @JoinColumn(name = "user_id")
    private User user;

    // getters and setters
}

@Repository
public interface UserRepository extends JpaRepository<User, Long> {
}

@Service
public class UserService {
    @Autowired
    private UserRepository userRepository;

    @Transactional
    public void deleteUser(Long userId) {
        userRepository.deleteById(userId);
    }
}