第一步：导入相关包
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.2.2</version>
</dependency> 第二步：定义数据操作接口
@Mapper
public interface UserMapper {
User findUserById(int id);
@Insert("insert into user(username,password) values(#{username},#{password})")
@Options(useGeneratedKeys = true,keyProperty = "id")
int insertUser(User user);
int insertUserById(User user);
} 这里如果加上@Mapper标签 那么主文件
Application里就不用添加@mappsacan 否则需要入口文件添加统一的扫描文件路径@MapperScan("com.example.mybtis.mapper")
public class MybtisApplication {
public static void main(String[] args) {
SpringApplication.run(MybtisApplication.class, args);
}
}
具体操作方法可以通过@Select @Insert等标签通过写SQL语句完成也可以定制配置文件
第四步：定义配置文件
<?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.example.mybtis.mapper.UserMapper">
<select id="findUserById" resultType="com.example.mybtis.entity.User">
select * from user where id = #{id}
</select>
<!--添加订单到order-->
<insert id="insertUserById" parameterType="com.example.mybtis.entity.User">
<selectKey resultType="java.lang.Integer" order="AFTER" keyProperty="id">
select LAST_INSERT_ID()
</selectKey>
insert into user(username,password)
values(#{username},#{password})
</insert>
</mapper> 注意：定义了配置文件那么配置里需要定义好mapp文件的路径如：
mybatis.mapper-locations= classpath:mapping/**.xml