<?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.demo.mapper.UserMapper">
<!-- 插入用户 -->
<insert id="insertUser" parameterType="com.example.demo.entity.User">
INSERT INTO user(name, email) VALUES(#{name}, #{email})
</insert>
<!-- 根据ID查询用户 -->
<select id="findUserById" parameterType="int" resultType="com.example.demo.entity.User">
SELECT * FROM user WHERE id = #{id}
</select>
<!-- 更新用户 -->
<update id="updateUser" parameterType="com.example.demo.entity.User">
UPDATE user SET name = #{name}, email = #{email} WHERE id = #{id}
</update>
<!-- 删除用户 -->
<delete id="deleteUser" parameterType="int">
DELETE FROM user WHERE id = #{id}
</delete>
<!-- 查询所有用户 -->
<select id="findAllUsers" resultType="com.example.demo.entity.User">
SELECT * FROM user
</select>
</mapper>
这段XML内容是一个MyBatis的Mapper配置文件,用于定义数据库操作的SQL语句。以下是对每个部分的解释:
-
XML声明和DOCTYPE声明:
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//myba