Springboot 抛出Failed to determine a suitable driver class异常原因

SpringBoot项目，已经依赖了MySQL驱动，却还是无法启动，通过问题排除，如果是启动项目，那么pom值

<packaging>pom</packaging>

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

不能定义在POM文件中