The server time zone value '�й���׼ʱ��' is unrecognized or represents more than one time zone.

报错信息

java.sql.SQLException: The server time zone value '�й���׼ʱ��' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support.
	......
Caused by: com.mysql.cj.exceptions.InvalidConnectionAttributeException: The server time zone value '�й���׼ʱ��' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support.
	......

错误配置

spring:
  datasource:
    url: jdbc:mysql://127.0.0.1:3306/orderingsystem?useUnicode=true&characterEncoding=UTF-8
    username: root
    password: root
    driver-class-name: com.mysql.cj.jdbc.Driver

正确配置

spring:
  datasource:
    url: jdbc:mysql://127.0.0.1:3306/orderingsystem?useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC
    username: root
    password: root
    driver-class-name: com.mysql.cj.jdbc.Driver

缺少serverTimezone=UTC配置报以上错误

随便说下

#如下配置则警告 the driver class is generally unnecessary.
driver-class-name: com.mysql.jdbc.Driver

Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.