mysql - 不同时区的 Hibernate @CreationTimestamp @UpdateTimestamp

Question

使用以下两个来存储更新和创建时间。

@CreationTimestamp
private Timestamp creationTime;

@UpdateTimestamp
private Timestamp updationTime;

当我创建新记录时，这两个记录都存储在 UTC 时区中。

+------------+----------------------------------+--------------+--------------+--------------------+--------------------+-----------------------+---------------------------+------+-------------------+---------------------+------------+------------+---------------------+---------------------+----------+
| meeting_id | analysis_description             | meeting_date | preread_date | first_version_date | reminder_sent_date | review_addressed_date | review_comments_addressed | tfls | first_record_flag | current_record_flag | created_by | updated_by | creation_time       | updation_time       | end_time |
+------------+----------------------------------+--------------+--------------+--------------------+--------------------+-----------------------+---------------------------+------+-------------------+---------------------+------------+------------+---------------------+---------------------+----------+
|          4 | BAF312A2122 - CRT 1 - LEGACY CRT | NULL         | NULL         | NULL               | NULL               | NULL                  | NULL                      |    0 | Y                 | Y                   | NULL       | NULL       | 2019-10-04 06:36:36 | 2019-10-04 06:36:36 | NULL     |
+------------+----------------------------------+--------------+--------------+--------------------+--------------------+-----------------------+---------------------------+------+-------------------+---------------------+------------+------------+---------------------+---------------------+----------+
1 row in set (0.00 sec)  

但是，如果我更新记录，创建时间戳将更改为我的本地时间戳。

+------------+----------------------------------+--------------+--------------+--------------------+--------------------+-----------------------+---------------------------+------+-------------------+---------------------+------------+------------+---------------------+---------------------+----------+
| meeting_id | analysis_description             | meeting_date | preread_date | first_version_date | reminder_sent_date | review_addressed_date | review_comments_addressed | tfls | first_record_flag | current_record_flag | created_by | updated_by | creation_time       | updation_time       | end_time |
+------------+----------------------------------+--------------+--------------+--------------------+--------------------+-----------------------+---------------------------+------+-------------------+---------------------+------------+------------+---------------------+---------------------+----------+
|          4 | BAF312A2122 - CRT 1 - LEGACY CRT | 2019-09-30   | 2019-09-30   | 2019-09-30         | 2019-09-30         | 2019-09-30            | yes                       |    1 | Y                 | Y                   | NULL       | NULL       | 2019-10-04 12:08:20 | 2019-10-04 06:38:20 | NULL     |
+------------+----------------------------------+--------------+--------------+--------------------+--------------------+-----------------------+---------------------------+------+-------------------+---------------------+------------+------------+---------------------+---------------------+----------+
1 row in set (0.00 sec)

而且两者都会更新，而不仅仅是更新时间。

我尝试了各种配置更改，但它们的行为都是相同的。

1. spring.jpa.properties.hibernate.jdbc.time_zone=UTC

2. 使用后置构造

   @SpringBootApplication
   public class IdotApplication {
   
   @PostConstruct
   void started() {
       TimeZone.setDefault(TimeZone.getTimeZone("UTC"));
   }
   
   public static void main(String[] args) {
       SpringApplication.run(IdotApplication.class, args);
   }
   

   }

3. 日期而不是时区

   @CreationTimestamp私有(private)日期创建时间；

4. @CreationTimestamp@Temporal(TemporalType.TIMESTAMP)私有(private)日期创建时间；

5. @Column(可更新=假)@CreationTimestamp私有(private)日期创建时间；

此外，serverTimezone=UTC 已与 useLegacyDatetimeCode=false 一起定义

spring.datasource.url=jdbc:mysql://localhost:3306/rmcdb?useUnicode=true&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC

Answer 1

这个问题是由于mysql的一个功能引起的，我使用mysql 5.7+，liquibase和原始sql来生成模式。

如果我在 mysql 中使用 timestamp 创建一列，它默认为自动更新。

mysql> create table test ( a timestamp );
Query OK, 0 rows affected (0.02 sec)

mysql> describe test;
+-------+-----------+------+-----+-------------------+-----------------------------+
| Field | Type      | Null | Key | Default           | Extra                       |
+-------+-----------+------+-----+-------------------+-----------------------------+
| a     | timestamp | NO   |     | CURRENT_TIMESTAMP | on update CURRENT_TIMESTAMP |
+-------+-----------+------+-----+-------------------+-----------------------------+
1 row in set (0.00 sec)

mysql>

创建新记录时，两个时间戳均采用 UTC 时区，因为 hibernate 覆盖了 mysql。

但是当记录更新时， on update current_timestamp from mysql 会触发，而 hibernate 不会执行任何操作，因为它是 @creationTimeStamp 因此它保留在 mysql 所设置的本地时区中。

为了解决这个问题，我将该字段定义为

creation_time timestamp null,
updation_time timestamp null

现在mysql不会干扰、更新等。所有这些都仅通过 hibernate 完成。

如果您发现解释有点令人困惑并且正在使用mysql，请阅读下面的文章以进行澄清。 https://dev.mysql.com/doc/refman/5.7/en/timestamp-initialization.html

希望它对某人有帮助。