据我了解,JpaRepository save()方法应该更新数据库中的实体。
我在MySQL中有一个名为REF_PERIOD的表,该表只有两列:code_id(即INT和主键)和code_name(即VARCHAR)。
这是我的实体:
@Data
@Entity
@Table(name = "REF_PERIOD")
public class PayRefPeriod {
@Id
@Column(name = "code_id")
private int codeId;
@Column(name = "code_name", length = 254, nullable = false)
private String codeName;
}
我的存储库:
@Repository
public interface PayRefPeriodRepository extends JpaRepository<PayRefPeriod, Integer> {
}
和控制器:
@Slf4j
@RestController
@RequestMapping("/api")
public class PayRefPeriodController {
@Autowired
private PayRefPeriodRepository payRefPeriodRepository;
// Get all pay reference periods
@GetMapping("/payrefperiods")
public List<PayRefPeriod> getAllPayRefPeriod() {
return payRefPeriodRepository.findAll();
}
// Create a new pay reference period
@PostMapping("/payrefperiods")
public PayRefPeriod createPayRefPeriod(@Valid @RequestBody PayRefPeriod payRefPeriod) {
return payRefPeriodRepository.save(payRefPeriod);
}
// Get a single pay reference period
@GetMapping("/payrefperiods/{id}")
public PayRefPeriod PayRefPeriod(@PathVariable(value = "id") int payRefPeriodId) {
return payRefPeriodRepository.findById(payRefPeriodId)
.orElseThrow(() -> new ResourceNotFoundException("PayRefPeriod", "id", payRefPeriodId));
}
// Update a pay reference period
@PutMapping("/payrefperiods/{id}")
public PayRefPeriod updatePayRefPeriod(@PathVariable(value = "id") int payRefPeriodId,
@Valid @RequestBody PayRefPeriod payRefPeriodDetails) {
PayRefPeriod payRefPeriod = payRefPeriodRepository.findById(payRefPeriodId)
.orElseThrow(() -> new ResourceNotFoundException("PayRefPeriod", "id", payRefPeriodId));
payRefPeriod.setCodeName(payRefPeriodDetails.getCodeName());
log.debug(payRefPeriod.toString());
return payRefPeriodRepository.save(payRefPeriod);
}
// Delete a pay reference period
@DeleteMapping("/payrefperiods/{id}")
public ResponseEntity<?> deletePayRefPeriod(@PathVariable(value = "id") int payRefPeriodId) {
PayRefPeriod payRefPeriod = payRefPeriodRepository.findById(payRefPeriodId)
.orElseThrow(() -> new ResourceNotFoundException("PayRefPeriod", "id", payRefPeriodId));
payRefPeriodRepository.delete(payRefPeriod);
return ResponseEntity.ok().build();
}
}
我希望updatePayRefPeriod方法更新我的实体(MySQL数据库中的ID为0),但是它会引发异常:java.sql.SQLIntegrityConstraintViolationException:密钥“ PRIMARY”的条目“ 0”重复。
我做错了什么?
答案 0 :(得分:2)
我想这可能是特定于mysql驱动程序的限制,当我们使用Java原语类型int
作为标识符时,它会受到限制。我建议您将codeId
的类型更改为其装箱的对象类型Integer
。
@Id
@Column(name = "code_id")
private Integer codeId;
因此,底层休眠在生成相应的更新查询时可以理解 null 标识符和非null而是 0 值标识符之间的区别。
答案 1 :(得分:-1)
尝试将sequenceGenerator和GeneratedValue添加到您的id列。
@Data
@Entity
@Table(name = "REF_PERIOD")
public class PayRefPeriod {
@SequenceGenerator(name = "generator", sequenceName = "REF_PERIOD_ID_SEQ")
@GeneratedValue(strategy = GenerationType.AUTO, generator = "generator")
@Id
@Column(name = "code_id")
private int codeId;
@Column(name = "code_name", length = 254, nullable = false)
private String codeName;
}