使用依赖

        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>dynamic-datasource-spring-boot-starter</artifactId>
            <version>4.3.0</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.33</version>
        </dependency>
        <dependency>
            <groupId>com.microsoft.sqlserver</groupId>
            <artifactId>mssql-jdbc</artifactId>
            <version>9.4.1.jre8</version>
        </dependency>

application.yml配置

spring:
  datasource:
    dynamic:
      primary: mysql
      datasource:
        mysql:
          driver-class-name: com.mysql.cj.jdbc.Driver
          url: jdbc:mysql://localhost:3306/xxl_job?useUnicode=true&allowPublicKeyRetrieval=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT%2B8
          username: root
          password: 123456
        sqlserver:
          driver-class-name: com.microsoft.sqlserver.jdbc.SQLServerDriver
          url: jdbc:sqlserver://ip:port;databaseName=dongbao_test;
          username: xxxx
          password: xxx
          druid:
            validation-query: SELECT 1
      strict: false
    hikari:
      pool-name: HikariCP
      minimum-idle: 5
      idle-timeout: 60000
      maximum-pool-size: 10
      auto-commit: true
      connection-test-query: SELECT 1

异常信息：

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 (the profiles dev are currently active)

[com/baomidou/mybatisplus/autoconfigure/MybatisPlusAutoConfiguration.class]: Unsatisfied dependency expressed through method 'sqlSessionFactory' parameter 0: Error creating bean with name 'dataSource' defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Hikari.class]: Failed to instantiate [com.zaxxer.hikari.HikariDataSource]: Factory method 'dataSource' threw exception with message: Failed to determine a suitable driver class
2024-05-27 17:46:00.875 [main] INFO  o.a.catalina.core.StandardService - Stopping service [Tomcat]
2024-05-27 17:46:00.925 [main] INFO  o.s.b.a.l.ConditionEvaluationReportLogger - 

Error starting ApplicationContext. To display the condition evaluation report re-run your application with 'debug' enabled.
2024-05-27 17:46:00.933 [main] ERROR 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 (the profiles dev are currently active).

解决方案：

错误的：
ps：我都使用多数据源了，你还不让自动注入datasource，有毒吧！

// 取消数据源自动注入
@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})

正解：

先注意，我们使用的是springboot3版本，然后去大佬的仓库找对应的依赖，源码仓库，或者GitHub文档，从github中明显看到

答案已经很明显了：

下面是我修正后的，修改完后项目运行一切正常

   <dependency>
      <groupId>com.baomidou</groupId>
      	<artifactId>dynamic-datasource-spring-boot3-starter</artifactId>
      <version>4.3.0</version>
    </dependency>

写在最后：
如果你开始使用你不熟悉的技术依赖，先去gitehub看一下大佬们的解释，会少花两天时间去百度一些花里胡哨的答案！