【发布时间】：2021-03-17 14:42:08
【问题描述】：
Spring Boot 2.4.0，DB 是 MySql 8。
每 15 秒使用 REST 从远程获取数据，并使用 saveAll() 将其存储到 MySql DB。
Which call the save() method for all the given entities.
所有数据都设置了 ID。
我希望如果 DB 没有这样的 id - 它将被插入。
如果此类 ID 已在 DB 中提供 - 它将被更新。
这里是从控制台截取的：
Hibernate:
insert
into
iot_entity
(controller_ref, description, device_id, device_ref, entity_type_ref, hw_address, hw_serial, image_ref, inventory_nr, ip6address1, ip6address2, ip_address1, ip_address2, latlng, location, mac_address, name, params, status, tenant, type, id)
values
(?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
...
2020-12-05 23:18:28.269 ERROR 15752 --- [ restartedMain] o.h.e.jdbc.batch.internal.BatchingBatch : HHH000315: Exception executing batch [java.sql.BatchUpdateException: Duplicate entry '1' for key 'iot_entity.PRIMARY'], SQL: insert into iot_entity (controller_ref, description, device_id, device_ref, entity_type_ref, hw_address, hw_serial, image_ref, inventory_nr, ip6address1, ip6address2, ip_address1, ip_address2, latlng, location, mac_address, name, params, status, tenant, type, id) values (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
2020-12-05 23:18:28.269 WARN 15752 --- [ restartedMain] o.h.engine.jdbc.spi.SqlExceptionHelper : SQL Error: 1062, SQLState: 23000
2020-12-05 23:18:28.269 ERROR 15752 --- [ restartedMain] o.h.engine.jdbc.spi.SqlExceptionHelper : Duplicate entry '1' for key 'iot_entity.PRIMARY'
2020-12-05 23:18:28.269 DEBUG 15752 --- [ restartedMain] o.s.orm.jpa.JpaTransactionManager : Initiating transaction rollback after commit exception
org.springframework.dao.DataIntegrityViolationException: could not execute batch; SQL [insert into iot_entity (controller_ref, description, device_id, device_ref, entity_type_ref, hw_address, hw_serial, image_ref, inventory_nr, ip6address1, ip6address2, ip_address1, ip_address2, latlng, location, mac_address, name, params, status, tenant, type, id) values (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)]; constraint [iot_entity.PRIMARY]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute batch
这里是如何获取和保存的样子：
@Override
@SneakyThrows
@Scheduled(fixedDelay = 15_000)
@Transactional(propagation = Propagation.REQUIRES_NEW)
public void fetchAndStoreData() {
IotEntity[] entities = restTemplate.getForObject(properties.getIotEntitiesUrl(), IotEntity[].class);
log.debug("ENTITIES:\n{}", mapper.writerWithDefaultPrettyPrinter().writeValueAsString(entities));
if (entities != null && entities.length > 0) {
entityRepository.saveAll(List.of(entities));
} else {
log.warn("NO entities data FETCHED !!!");
}
}
此方法每 15 秒运行一次。
实体：
@Data
@Entity
@NoArgsConstructor
@EqualsAndHashCode(of = {"id"})
@ToString(of = {"id", "deviceId", "entityTypeRef", "ipAddress1"})
public class IotEntity implements Serializable {
private static final long serialVersionUID = 1L;
@Id
private Integer id;
// other fields
和存储库：
public interface EntityRepository extends JpaRepository<IotEntity, Integer> {
}
这里是为 iot 实体截取的 JSON 格式：
2020-12-05 23:18:44.261 DEBUG 15752 --- [pool-3-thread-1] EntityService : ENTITIES:
[ {
"id" : 1,
"controllerRef" : null,
"name" : "Local Controller Unterföhring",
"description" : "",
"deviceId" : "",
...
所以ID肯定设置好了。
此外，为项目启用了批处理。应该不会对储蓄产生任何影响。
我不明白为什么它会尝试插入新实体而不是更新现有实体？
为什么不能区分新旧实体？
更新：
为实体实现持久化：
@Data
@Entity
@NoArgsConstructor
@EqualsAndHashCode(of = {"id"})
@ToString(of = {"id", "deviceId", "entityTypeRef", "ipAddress1"})
public class IotEntity implements Serializable, Persistable<Integer> {
private static final long serialVersionUID = 1L;
@Id
private Integer id;
@Override
public boolean isNew() {
return false;
}
@Override
public Integer getId() {
return this.id;
}
但是，它失败并出现同样的异常 - Duplicate entry '1' for key 'iot_entity.PRIMARY'
如果我要添加@GeneratedValue，如下所示：
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer id;
它不会失败。但是，它会自行更新 ID 值。
例如，它使用id = 15 获取：
[ {
"id" : 15,
"carParkRef" : 15,
"name" : "UF Haus 1/2",
并且应该像下面这样保存：
实际上它有id = 2：
而且是不正确的。
尝试添加到存储服务：
private final EntityManager entityManager;
...
List.of(carParks).forEach(entityManager::merge);
失败并出现相同的异常（无论是否实现 Persistable）。它尝试插入值 - insert into ... Duplicate entry '15' for key '... .PRIMARY'
来自application.yml的片段：
spring:
# ===============================
# = DATA SOURCE
# ===============================
datasource:
url: jdbc:mysql://localhost:3306/demo_db
username: root
password: root
initialization-mode: always
# ===============================
# = JPA / HIBERNATE
# ===============================
jpa:
show-sql: true
generate-ddl: true
hibernate:
ddl-auto: update
properties:
hibernate:
format_sql: true
generate_statistics: true
在这里你可以看到pom file content。
如何解决这个问题？
【问题讨论】：
标签： java spring-boot hibernate spring-data-jpa save