若在运行SpringBoot项目时，出现如下错误：
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).
Disconnected from the target VM, address: '127.0.0.1:31456', transport: 'socket'出现该错误的原因是：没有连接数据库，需要在application.properties（下图）中添加配置数据库的代码：
配置数据库的代码为：
# 数据库的配置信息
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/myblog?characterEncoding=utf8
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
添加完毕后，即可成功运行。
