【BUG集绵】Failed to configure a DataSource: ‘url‘ attribute is not specified and no embedded datasource

【BUG】Failed to configure a DataSource: ‘url’ attribute is not specified and no embedded datasource could be configured.

报错截图：

报错内容：

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2023-08-10 18:31:09.742 ERROR 2220 --- [           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).

报错原因分析：数据库配置异常。

报错溯源，一般可以从如下几点着手：

（1）首先检查项目的application.yml或application.properties中是否有添加数据库相关配置。比如：

spring:
  datasource:
    druid:
      driver-class-name: com.mysql.cj.jdbc.Driver
      url: jdbc:mysql://localhost:3306/xcplus_content?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=utf-8&zeroDateTimeBehavior=convertToNull&useSSL=false&allowPublicKeyRetrieval=true
      username: root
      password: root

（2）如果项目是多模块开发，同级模块都有application.yml 或 application.properties同名文件的话，
可以尝试修改为不同的规范文件名，比如：application-dev.yml
（3）在SpringBootApplication注解中进行数据库配置的排除，即@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})。
（4）项目是多模块开发且不同模块中的配置文件，以application-*.yml的形式命名,比如application-mapper.yml,application-service.yml等，然后在最顶层的shop-web模块配置文件中，通过spring.profiles.active进行激活配置

spring:
  profiles:
  	# 加载不同模块的配置文件
    active: mapper,service

（5）其他原因：Resources资源目录下的application.yml或 application.properties 的默认名称有被修改，导致程序启动时主启动类的配置文件无法被加载。这时需要修改回application.yml来才行。