我这里是在springboot子模块里发生的错误，如下

Exception encountered during context initialization - cancelling refresh attempt: 
org.springframework.beans.factory.UnsatisfiedDependencyException:
Error creating bean with name 'dataShowController': Unsatisfied dependency expressed through field 'dataShowService';  nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException:
Error creating bean with name 'dataShowServiceImp': Unsatisfied dependency expressed through field 'dauMapper';
nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException:
Error creating bean with name 'dauMapper' defined in file 
...

Description:

Cannot determine embedded database driver class for database type NONE

Action:

If you want an embedded database please put a supported one on the classpath. If you have database settings to be loaded from a particular profile you may need to active it (no profiles are currently active).

在这里引起的直接原因很简单，就是因为这个子模块声明被莫名奇妙的从父模块pom文件里删除了。可能有的小伙伴在导入一些工程或按错快捷键时会遇到这样的弹框，或者像我一样某明奇妙的掉坑了。

然后是一脸问号？我没删这个模块呀，直接No或关闭会话框。然后运行时就出现上面的错误了，同时发现子模块的pom文件颜色变成了下面这个样子：

问前辈说是idea的bug，在此直接在父模块pom中手动添加子模块声明。如下：

 <modules>
...
        <module>dataShowWeb</module>
   ...
</modules>

刷新一下maven工程问题解决。