Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could

刚创建的 Spring Boot 项目，启动后输出：

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2018-07-03 13:52:44.978 ERROR 6161 --- [  restartedMain] o.s.b.d.LoggingFailureAnalysisReporter   : 

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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).

        

          
        
        
        

          

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这个错误的原因是因为：

 Spring Boot 虽然做了很多默认的配置，但是它没办法知道你用什么数据库，数据库名称、用户名、密码是什么啊。

打开文件“src/main/resources/application.properties”，配置数据库相关信息：

spring.datasource.url=jdbc:mysql://localhost:3306/databaseName?useUnicode=true&zeroDateTimeBehavior=convertToNull&autoReconnect=true
spring.datasource.username=userName
spring.datasource.password=password
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

        

          
        
        
        

          

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在 1.5版本的时候可以使用：

spring.datasource.type=org.apache.tomcat.jdbc.pool.DataSource

        

          
        
        
        

          

          AI 代码解读
        
      
      

在2.0版本却不行了。

感觉改动非常大。