1. 引入依赖

    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <scope>8.0.19</scope>
    </dependency>

    <!--引用多数据源启动器-->
    <dependency>
      <groupId>com.baomidou</groupId>
      <artifactId>dynamic-datasource-spring-boot-starter</artifactId>
      <version>3.5.0</version>
    </dependency>

2. application.yml 配置文件

primary: dev：默认数据源名称
lazy: false：懒加载，true表示调用数据库才加载，false表示项目启动就加载

spring:
  datasource:
    dynamic:
      primary: dev
      lazy: false
      datasource:
        dev:
          driver-class-name: com.mysql.cj.jdbc.Driver
          url: jdbc:mysql://192.168.56.128:3396/mybatis_plus?useSSL=false&serverTimezone=GMT%2B8&allowPublicKeyRetrieval=true
          username: root
          password: root
        dev2:
          driver-class-name: com.mysql.cj.jdbc.Driver
          url: jdbc:mysql://192.168.56.128:3396/mybatis_plus2?useSSL=false&serverTimezone=GMT%2B8&allowPublicKeyRetrieval=true
          username: root
          password: root

3. 结合注解使用

@DS("dev2") ：引用数据库dev2，在controller、mapper、service都可以使用！

注：不使用注解，使用默认数据源dev

@RestController
@RequestMapping("user")
@DS("dev2") //引用数据库dev2
@CrossOrigin //解决跨域问题
public class UserController {

    @Resource
    UserService userService;
    @Resource
    UserMapper userMapper;

    @GetMapping("/{pageNum}/{pageSize}")
    public IPage<User> index(@PathVariable Integer pageNum, @PathVariable Integer pageSize) {
        Page<User> page = userService.page(new Page<User>(pageNum, pageSize));
        return page;
    }

    @GetMapping("/select")
    public String select() {
        List<User> users = userMapper.selectList(null);
        return users.toString();
    }
}