解决报错：Failed to configure a DataSource: ‘url‘ attribute is not specified and no embedded datasour

问题

服务启动失败，报错如下：

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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).

查询资料发现Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured.这个报错是因为引入了下面的依赖而没有配置四大参数：（mybatis的依赖也会包含这个依赖）

<dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>

所谓四大参数：

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/xxxx
    username: root
    password: root
    driver-class-name: com.mysql.jdbc.Driver

问题解决：

发现启动的服务中并没有引入上述依赖，于是检查引入的其他模块，果然在该模块里面发现了mybatis-plus的依赖（该依赖包含jdbc的依赖）。

所以可以把这个模块从依赖里去除，或者加入四大参数的配置。

参考：参考文档