场景

在开发过程中我们常常会用到两个数据库，一个数据用来实现一些常规的增删改查，另外一个数据库用来实时存数据。进行数据的统计分析。可以读写分离。可以更好的优化和提高效率；
或者两个数据存在业务分离的时候也需要多个数据源来实现

使用方式

1、application.properties 中数据库配置

#数据库配置
spring.datasource.db1.jdbc-url=jdbc:mysql://localhost:3306/gds?useUnicode=true&characterEncoding=utf8&serverTimezone=Asia/Shanghai&useSSL=false 
spring.datasource.db1.username=root
spring.datasource.db1.password=root
spring.datasource.db1.driver-class-name=com.mysql.cj.jdbc.Driver

spring.datasource.db2.jdbc-url=jdbc:mysql://localhost:3306/zkhx?useUnicode=true&characterEncoding=utf8&serverTimezone=Asia/Shanghai&useSSL=false
spring.datasource.db2.username=root
spring.datasource.db2.password=root
spring.datasource.db2.driver-class-name=com.mysql.cj.jdbc.Driver

config文件配置

1、配置 spring.datasource.db1

注：basePackages = “com.zkhx.dao.master”：
prefix = “spring.datasource.db1”
绑定master目录下使用的是数据库db1 也就是gds

package com.zkhx.config;

import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;

import javax.sql.DataSource;


@Configuration
// 配置mybatis的接口类放的地方
@MapperScan(basePackages = "com.zkhx.dao.master", sqlSessionFactoryRef = "dbSqlSessionFactory")
public class DataSourceConfig {

    @Bean(name = "db")
    @Primary
    @ConfigurationProperties(prefix = "spring.datasource.db1")
    public DataSource getDateSource1() {
        return DataSourceBuilder.create().build();
    }

    @Bean
    @ConfigurationProperties(prefix = "mybatis.configuration")
    public org.apache.ibatis.session.Configuration configuration() {
        return new org.apache.ibatis.session.Configuration();
    }


    @Bean(name = "dbSqlSessionFactory")
    @Primary
    public SqlSessionFactory test1SqlSessionFactory(@Qualifier("db") DataSource datasource, org.apache.ibatis.session.Configuration configuration)
            throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(datasource);
        bean.setConfiguration(configuration);
        bean.setMapperLocations(
                // 设置mybatis的xml所在位置
                new PathMatchingResourcePatternResolver().getResources("classpath*:mapper/master/*.xml"));
        return bean.getObject();
    }
    @Bean("dbSqlSessionTemplate")
    // 表示这个数据源是默认数据源
    @Primary
    public SqlSessionTemplate test1sqlsessiontemplate(
            @Qualifier("dbSqlSessionFactory") SqlSessionFactory sessionfactory) {
        return new SqlSessionTemplate(sessionfactory);
    }
}

2、配置 spring.datasource.db2

package com.zkhx.config;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Configuration;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;

import javax.sql.DataSource;

@Configuration
@MapperScan(basePackages = "com.zkhx.dao.vice", sqlSessionFactoryRef = "db2SqlSessionFactory")
public class DataSourceViceConfig {
    @Bean(name = "db2")
    @ConfigurationProperties(prefix = "spring.datasource.db2")
    public DataSource getDateSource2() {
        return DataSourceBuilder.create().build();
    }
    @Bean(name = "db2SqlSessionFactory")
    public SqlSessionFactory test2SqlSessionFactory(@Qualifier("db2") DataSource datasource)
            throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(datasource);
        bean.setMapperLocations(
                new PathMatchingResourcePatternResolver().getResources("classpath*:mapper/vice/*.xml"));
        return bean.getObject();
    }
    @Bean("db2SqlSessionTemplate")
    public SqlSessionTemplate test2sqlsessiontemplate(
            @Qualifier("db2SqlSessionFactory") SqlSessionFactory sessionfactory) {
        return new SqlSessionTemplate(sessionfactory);
    }
}

3、截图

在这里插入图片描述

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.zkhx.dao.vice.StDBDataDao">
	 
</mapper>