在使用springboot连接数据库启动项目出现错误：
Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could
完整错误信息：
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APPLICATION FAILED TO START
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Description:
Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured.
Reason: Failed to determine a suitable driver class
Action:
Consider the following:
If you want an embedded database (H2, HSQL or Derby), please put it on the classpath.
If you have database settings to be loaded from a particular profile you may need to activate it (no profiles are currently active).
在yml文件修改了正确的url后，在pom.xml中添加当前使用的mysql版本，即可成功运行。
spring:
datasource:
url: jdbc:mysql://localhost:3306/databasename?useUnicode=true&characterEncoding=utf8&useSSL=false&serverTimezone=Asia/Shanghai&tinyInt1isBit=false
username: root
password: 010618
driver-class-name: com.mysql.cj.jdbc.Driver
