maven实现与数据库交互

1.导入数据库需要的依赖（引入了依赖，一定要刷新maven）

<dependency> 

 <groupId>org.mybatis.spring.boot</groupId> 

 <artifactId>mybatis-spring-boot-starter</artifactId>

 <version>2.1.1</version> 

</dependency> 

<dependency> 

 <groupId>mysql</groupId>

 <artifactId>mysql-connector-java</artifactId>

 <scope>runtime</scope> 

</dependency>

2.

 3.配置yml文件

spring:

 datasource:

  url: jdbc:mysql://localhost:3306/qcby_db?useUnicode=true&characterEncoding=utf-8&serverTimezone=CTT

  username: root

  password: driver-class-name: com.mysql.cj.jdbc.Driver

 mybatis:

  mapper-locations: classpath:mapper/*.xml #对应mapper映射xml文件所在路径 

  type-aliases-package: com.xxxx.entity #对应实体类路径

 4.切换成project模式，在resources下新建一个”mapper“的Directory

-----------------------------------Mybatis 整合完毕-----------------------------------------------

5.测试，数据库创建表

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10mapper和xml建立联系

<?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.yglh.mapper.TestMapper"> 

</mapper>

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16.service调用mapper层

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------------------------------------------------------------------完成--------------------------

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