Failed to obtain JDBC Connection; nested exception is 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: java.sql.SQLException: The server time zone value=問題解決，由於使用了新版mysql等數據庫
解決：在jdbc連接的url后面添加serverTimezone=CST
例如：
jdbc:mysql://localhost:3306/demo改為
jdbc:mysql://localhost:3306/demo?serverTimezone=CST
原因：使用mysql的jdbc驅動最新版（6.0+）時，會遇到數據庫和系統時區差異引起的問題。
注：CST代表的是中國上海時間（與北京時間，東八區相同）。
改后：
spring:
datasource:
driver-class-name: com.mysql.cj.jdbc.Driver
username: root
password: 1234
url: jdbc:mysql://localhost:3306/mydatabase?serverTimezone=CST&useUnicode=true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull&useSSL=true