前言
MyBatis 多數據源配置,最近在項目建設中,需要在原有系統上擴展一個新的業務模塊,特意將數據庫分庫,以便減少復雜度。本文直接以簡單的代碼示例,如何對 MyBatis 多數據源配置。
准備
創建數據庫
db_test
SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;
-- ----------------------------
-- Table structure for t_user
-- ----------------------------
DROP TABLE IF EXISTS `t_user`;
CREATE TABLE `t_user` (
`id` int(8) NOT NULL AUTO_INCREMENT COMMENT 'ID',
`user_name` varchar(20) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL COMMENT '用戶姓名',
`user_sex` char(1) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL COMMENT '用戶性別',
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=23 DEFAULT CHARSET=utf8;
-- ----------------------------
-- Records of t_user
-- ----------------------------
BEGIN;
INSERT INTO `t_user` VALUES (1, '劉備', '男');
INSERT INTO `t_user` VALUES (2, '孫尚香', '女');
INSERT INTO `t_user` VALUES (3, '周瑜', '男');
INSERT INTO `t_user` VALUES (4, '小喬', '女');
INSERT INTO `t_user` VALUES (5, '諸葛亮', '男');
INSERT INTO `t_user` VALUES (6, '黃月英', '女');
INSERT INTO `t_user` VALUES (7, '關羽', '男');
INSERT INTO `t_user` VALUES (8, '張飛', '男');
INSERT INTO `t_user` VALUES (9, '趙雲', '男');
INSERT INTO `t_user` VALUES (10, '黃總', '男');
INSERT INTO `t_user` VALUES (11, '曹操', '男');
INSERT INTO `t_user` VALUES (12, '司馬懿', '男');
INSERT INTO `t_user` VALUES (13, '貂蟬', '女');
INSERT INTO `t_user` VALUES (14, '呂布', '男');
INSERT INTO `t_user` VALUES (15, '馬超', '男');
INSERT INTO `t_user` VALUES (16, '魏延', '男');
INSERT INTO `t_user` VALUES (17, '孟獲', '男');
INSERT INTO `t_user` VALUES (18, '大喬', '女');
INSERT INTO `t_user` VALUES (19, '劉嬋', '男');
INSERT INTO `t_user` VALUES (20, '姜維', '男');
INSERT INTO `t_user` VALUES (21, '廖化', '男');
INSERT INTO `t_user` VALUES (22, '關平', '男');
COMMIT;
SET FOREIGN_KEY_CHECKS = 1;
dbb_test2
SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;
-- ----------------------------
-- Table structure for t_hero
-- ----------------------------
DROP TABLE IF EXISTS `t_hero`;
CREATE TABLE `t_hero` (
`id` int(11) NOT NULL AUTO_INCREMENT COMMENT 'ID',
`hero_code` varchar(32) DEFAULT NULL COMMENT '英雄編碼',
`hero_name` varchar(20) DEFAULT NULL COMMENT '英雄名稱',
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;
-- ----------------------------
-- Records of t_hero
-- ----------------------------
BEGIN;
INSERT INTO `t_hero` VALUES (1, '001', '德瑪西亞');
COMMIT;
SET FOREIGN_KEY_CHECKS = 1;
構建項目,項目目錄結構
pom 文件
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.9.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>cn.zwqh</groupId>
<artifactId>spring-boot-mybatis-mulidatasource</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>spring-boot-mybatis-mulidatasource</name>
<description>spring-boot-mybatis-mulidatasource</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<!-- 熱部署模塊 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<optional>true</optional> <!-- 這個需要為 true 熱部署才有效 -->
</dependency>
<!-- mysql 數據庫驅動. -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<!-- mybaits -->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.1.0</version>
</dependency>
<!-- alibaba的druid數據庫連接池 -->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>1.1.20</version>
</dependency>
<!-- pagehelper -->
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper-spring-boot-starter</artifactId>
<version>1.2.12</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
這里使用了alibaba的druid數據庫連接池,Druid 能夠提供強大的監控和擴展功能。這里我們暫時只做簡單的應用。
配置文件
#master 數據源配置
master.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
master.datasource.url=jdbc:mysql://127.0.0.1:3306/db_test?useUnicode=true&characterEncoding=UTF-8&useSSL=true
master.datasource.username=root
master.datasource.password=zwqh@0258
#slave 數據源配置
slave.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
slave.datasource.url=jdbc:mysql://127.0.0.1:3306/db_test2?useUnicode=true&characterEncoding=UTF-8&useSSL=true
slave.datasource.username=root
slave.datasource.password=zwqh@0258
#mybatis
mybatis.mapper-locations=classpath:/mapper/**/*Mapper.xml
數據源配置
MasterDataSourceConfig 對應數據庫 db_test
@Configuration
@MapperScan(basePackages = "cn.zwqh.springboot.dao.master", sqlSessionFactoryRef = "masterSqlSessionFactory")
public class MasterDataSourceConfig {
@Value("${master.datasource.driver-class-name}")
private String driverClassName;
@Value("${master.datasource.url}")
private String url;
@Value("${master.datasource.username}")
private String username;
@Value("${master.datasource.password}")
private String password;
@Bean(name = "masterDataSource")
@Primary
public DataSource dataSource() {
DruidDataSource dataSource = new DruidDataSource();
dataSource.setDriverClassName(this.driverClassName);
dataSource.setUrl(this.url);
dataSource.setUsername(this.username);
dataSource.setPassword(this.password);
return dataSource;
}
@Bean(name = "masterSqlSessionFactory")
@Primary
public SqlSessionFactory sqlSessionFactory(@Qualifier("masterDataSource") DataSource dataSource) throws Exception {
SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
bean.setDataSource(dataSource);
bean.setMapperLocations(
new PathMatchingResourcePatternResolver().getResources("classpath*:/mapper/master/*Mapper.xml"));
return bean.getObject();
}
@Bean(name = "masterTransactionManager")
@Primary
public DataSourceTransactionManager transactionManager(@Qualifier("masterDataSource") DataSource dataSource) {
return new DataSourceTransactionManager(dataSource);
}
@Bean(name = "masterSqlSessionTemplate")
@Primary
public SqlSessionTemplate testSqlSessionTemplate(
@Qualifier("masterSqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
return new SqlSessionTemplate(sqlSessionFactory);
}
}
SlaveDataSourceConfig 對應數據庫 db_test2
@Configuration
@MapperScan(basePackages = "cn.zwqh.springboot.dao.slave", sqlSessionFactoryRef = "slaveSqlSessionFactory")
public class SlaveDataSourceConfig {
@Value("${slave.datasource.driver-class-name}")
private String driverClassName;
@Value("${slave.datasource.url}")
private String url;
@Value("${slave.datasource.username}")
private String username;
@Value("${slave.datasource.password}")
private String password;
@Bean(name = "slaveDataSource")
public DataSource dataSource() {
DruidDataSource dataSource = new DruidDataSource();
dataSource.setDriverClassName(this.driverClassName);
dataSource.setUrl(this.url);
dataSource.setUsername(this.username);
dataSource.setPassword(this.password);
return dataSource;
}
@Bean(name = "slaveSqlSessionFactory")
public SqlSessionFactory sqlSessionFactory(@Qualifier("slaveDataSource") DataSource dataSource) throws Exception {
SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
bean.setDataSource(dataSource);
bean.setMapperLocations(
new PathMatchingResourcePatternResolver().getResources("classpath*:/mapper/slave/*Mapper.xml"));
return bean.getObject();
}
@Bean(name = "slaveTransactionManager")
public DataSourceTransactionManager transactionManager(@Qualifier("slaveDataSource") DataSource dataSource) {
return new DataSourceTransactionManager(dataSource);
}
@Bean(name = "slaveSqlSessionTemplate")
public SqlSessionTemplate testSqlSessionTemplate(
@Qualifier("masterSqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
return new SqlSessionTemplate(sqlSessionFactory);
}
}
多個數據源在使用的過程中必須指定主庫,不然會報錯。
@MapperScan(basePackages = "cn.zwqh.springboot.dao.slave") 指定對應 Dao 層的掃描路徑。
dao 層和 xml 層
db_test 數據庫的 dao 層在 cn.zwqh.springboot.dao.master
包下,db_test2 數據庫的 dao 層在 cn.zwqh.springboot.dao.slave
包下。
UserDao
public interface UserDao {
List<UserEntity> getAll();
}
HeroDao
public interface HeroDao {
List<Hero> getAllHero();
}
db_test 數據庫的 xml 層在 /mapper/master/ 文件路徑下,db_test2 數據庫的 xml 層在 /mapper/slave/ 文件路徑下。
UserMapper.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.4//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="cn.zwqh.springboot.dao.master.UserDao">
<resultMap type="cn.zwqh.springboot.model.UserEntity" id="user">
<id property="id" column="id"/>
<result property="userName" column="user_name"/>
<result property="userSex" column="user_sex"/>
</resultMap>
<!-- 獲取所有用戶 -->
<select id="getAll" resultMap="user">
select * from t_user
</select>
</mapper>
HeroMapper.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.4//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="cn.zwqh.springboot.dao.slave.HeroDao">
<resultMap type="cn.zwqh.springboot.model.Hero" id="hero">
<id property="id" column="id"/>
<result property="heroCode" column="hero_code"/>
<result property="heroName" column="hero_name"/>
</resultMap>
<!-- 獲取所有用戶 -->
<select id="getAllHero" resultMap="hero">
select * from t_hero
</select>
</mapper>
測試
測試可以使用 SpringBootTest,也可以放到 Controller中,個人習慣用 Controller。
@RestController
@RequestMapping("/test")
public class TestController {
@Autowired
private UserDao userDao;
@Autowired
private HeroDao heroDao;
/**
* 查找所有用戶
* @return
*/
@RequestMapping("/getAllUser")
public List<UserEntity> getAllUser(){
return userDao.getAll();
}
/**
* 查找所有英雄
* @return
*/
@RequestMapping("/getAllHero")
public List<Hero> getAllHero(){
return heroDao.getAllHero();
}
}
瀏覽器直接訪問:http://127.0.0.1:8080/test/
加上相關測試路徑即可。
總結
多數據源一般用於主從模式或者按業務分庫。
示例代碼
非特殊說明,本文版權歸 朝霧輕寒 所有,轉載請注明出處.
原文標題:Spring Boot 2.X(五):MyBatis 多數據源配置
原文地址: https://www.zwqh.top/article/info/12
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