多数据源
一、依赖

 <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-aop</artifactId>
        </dependency>

        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>dynamic-datasource-spring-boot-starter</artifactId>
            <version>3.2.1</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>com.microsoft.sqlserver</groupId>
            <artifactId>mssql-jdbc</artifactId>
            <scope>runtime</scope>
        </dependency>
         <!--mybatis-plus 依赖-->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.3.1.tmp</version>
        </dependency>

二、yml数据库配置

spring:
  datasource:
    dynamic:
      primary: db233
      datasource:
        db233:
          jdbc-url: jdbc:sqlserver://120.0.0.1:1433;database=db1
          username: sa
          password: 123456
          driver-class-name: com.microsoft.sqlserver.jdbc.SQLServerDriver
          hikari:
            maximum-pool-size: 12
            minimum-idle: 5
            idle-timeout: 300000
            connection-timeout: 20000
            connection-test-query: select 1

        db231:
          jdbc-url: jdbc:sqlserver://120.0.0.1:1433;database=db2
          username: sa
          password: 123456
          driver-class-name: com.microsoft.sqlserver.jdbc.SQLServerDriver
          hikari:
            maximum-pool-size: 12
            minimum-idle: 5
            idle-timeout: 300000
            connection-timeout: 20000
            connection-test-query: select 1

        db231e:
          jdbc-url: jdbc:sqlserver://120.0.0.1:1433;database=db3
          username: sa
          password: 123456
          driver-class-name: com.microsoft.sqlserver.jdbc.SQLServerDriver
          hikari:
            maximum-pool-size: 12
            minimum-idle: 5
            idle-timeout: 300000
            connection-timeout: 20000
            connection-test-query: select 1
      durid:
        initial-size: 1
        max-active: 20
        min-idle: 1
        max-wait: 60000

三、配置文件

@Configuration
@MapperScan(basePackages = "com.xxxx.mapper.db231", sqlSessionFactoryRef = "db231SqlSessionFactory")
public class Db231DataSourceConfig {
    @Bean("db231DataSource")
    @ConfigurationProperties(prefix = "spring.datasource.dynamic.datasource.db231")
    public DataSource db231DataSource() {
        return DataSourceBuilder.create().build();
    }


    @Bean("db231SqlSessionFactory")
    public SqlSessionFactory db231SqlSessionFactory(@Qualifier("db231DataSource") DataSource dataSource) throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath*:mapper/db231/*.xml"));
        return bean.getObject();
    }


    @Bean("db231SqlSessionTemplate")
    public SqlSessionTemplate db231SqlSessionTemplate(@Qualifier("db231SqlSessionFactory") SqlSessionFactory sqlSessionFactory) {
        return new SqlSessionTemplate(sqlSessionFactory);
    }

    @Bean(name = "db231SqlSessionManager")
    public DataSourceTransactionManager db231SqlSessionManager() {
        return new DataSourceTransactionManager(db231DataSource());
    }
}

@Configuration
@MapperScan(basePackages = "com.xxxx.mapper.db231e", sqlSessionFactoryRef = "db231eSqlSessionFactory")
public class Db231eDataSourceConfig {
    @Bean("db231eDataSource")
    @ConfigurationProperties(prefix = "spring.datasource.dynamic.datasource.db231e")
    public DataSource db231eDataSource() {
        return DataSourceBuilder.create().build();
    }


    @Bean("db231eSqlSessionFactory")
    public SqlSessionFactory db231eSqlSessionFactory(@Qualifier("db231eDataSource") DataSource dataSource) throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath*:mapper/db231e/*.xml"));
        return bean.getObject();
    }

    @Bean("db231eSqlSessionTemplate")
    public SqlSessionTemplate db231eSqlSessionTemplate(@Qualifier("db231eSqlSessionFactory") SqlSessionFactory sqlSessionFactory) {
        return new SqlSessionTemplate(sqlSessionFactory);
    }

    @Bean(name = "db231eSqlSessionManager")
    public DataSourceTransactionManager db231eSqlSessionManager() {
        return new DataSourceTransactionManager(db231eDataSource());
    }
}

@Configuration
@MapperScan(basePackages = "com.xxxx.mapper.db233", sqlSessionFactoryRef = "db233SqlSessionFactory")
public class Db233DataSourceConfig {

    @Primary
    @Bean("db233DataSource")
    @ConfigurationProperties(prefix = "spring.datasource.dynamic.datasource.db233") //读取application.yml中的配置参数映射成为一个对象
    public DataSource db233DataSource(){
        return DataSourceBuilder.create().build();
    }

    @Primary
    @Bean("db233SqlSessionFactory")
    public SqlSessionFactory db233SqlSessionFactory(@Qualifier("db233DataSource") DataSource dataSource) throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        // mapper的xml形式文件位置必须要配置，不然将报错：no statement （这种错误也可能是mapper的xml中，namespace与项目的路径不一致导致）
        bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath*:mapper/db233/*.xml"));
        return bean.getObject();
    }
    @Primary
    @Bean("db233SqlSessionTemplate")
    public SqlSessionTemplate db233SqlSessionTemplate(@Qualifier("db233SqlSessionFactory") SqlSessionFactory sqlSessionFactory){
        return new SqlSessionTemplate(sqlSessionFactory);
    }


    @Primary
    @Bean(name = "db233SqlSessionManager")
    public DataSourceTransactionManager db233SqlSessionManager() {
        return new DataSourceTransactionManager(db233DataSource());
    }
}