背景：
导入别人的项目，却报错：
Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled. 2022-05-06 23:35:15.267 ERROR 12944 --- [ main] o.s.b.d.LoggingFailureAnalysisReporter : *************************** APPLICATION FAILED TO START *************************** 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). Process finished with exit code 1
这是一个常见的问题，如果试了很多都不行，可能是这个原因，以下是没解决前截图：
注意看：
1、 resources 其实只是一个普通的文件夹而已
2、配置文件里， spring.datasource.url 是灰色的，而 spring.datasource.password 却是有颜色的
解决步骤：右击 resources 文件夹，然后选择 Mark Directory as ，然后选择 Resources Root 即可：
修改好之后：
这样就不会报错了！
其他参考文章：
