Mybatis的mapper.xml配置文件——详解

红太狼 2022-03-15 07:06 262阅读 0赞

<?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.itheima.mapper.UserMapper">
    	
    	<sql id="select">
    		select * from user
    	</sql>
    	
    	<select id="findUserById" parameterType="int" resultType="user">
    		
    		<include refid="select"></include>
    		where id = #{id}
    	</select>
    	
    	<select id="findAllOrders" resultMap="orders">
    		select * from orders
    	</select>
    	
    	<resultMap type="Orders" id="orders">
    		<id property="id" column="id"/>
    		<result property="userId" column="user_id"/>
    	</resultMap>
    	
    	<insert id="addUser" parameterType="user">
    		
    		 <selectKey keyColumn="id" keyProperty="id" order="AFTER" resultType="int">
    		 	select LAST_INSERT_ID()
    		 </selectKey>
    		insert into user
    		(username,sex,address)
    		values(#{username},#{sex},#{address})
    	</insert>
    	
    	<select id="findUserBySexAndUsername" parameterType="User" resultType="user">
    		
    		<include refid="select"></include>
    		
    		<where>
    		
    		<if test="sex != null and sex != ''">
    			and sex = #{sex} 
    		</if>
    		<if test="username != null and username != ''">
    			and username like '%${username}%'
    		</if>
    		</where>
    	</select>
    	
    	
    	
    	<select id="findUserByIds" parameterType="QueryVo" resultType="user">
    		<include refid="select"></include>
    		<where>
    		
    		<foreach collection="ids" item="id" open="id in(" close=")" separator=",">
    			#{id}
    		</foreach>
    		</where>
    	</select>
    </mapper>