11月5日 电商 周一

<?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.hao.mapper.StudentMapper">
	<select id="findStuList" resultType="map">
select s.id,s.name,s.cometime,GROUP_CONCAT(c.name,'-') course,sum(study.scount) sum,sum(study.scount-1) count from t_student s 
	left join t_study study on s.id = study.sid
	left join t_course c on study.cid = c.id
	group by s.id 
	</select>
	
	<select id="findreStuList" resultType="map">
select s.id,s.name,s.cometime,GROUP_CONCAT(c.name,'-') course,sum(study.scount) sum,sum(study.scount-1) count from t_student s 
	left join t_study study on s.id = study.sid
	left join t_course c on study.cid = c.id
	group by s.id 
	</select>
	
	<update id="stuUp" parameterType="int">
		update t_study set studying = 0 where sid = #{id}
	</update>
	
	<update id="stuDown" parameterType="int">
		update t_study set scount=scount+1 where studying = 1 and sid = #{id}
	</update>
	
	<select id="previd" resultType="int" parameterType="int">
		select max(cid) from t_study where cid &lt;=5 and sid=#{id} 
	</select>
	
	<insert id="addCourse" parameterType="int">
		insert into t_study values(null,#{id},#{i},1,1)
	</insert>
	
</mapper>

救出自己的唯一法子便是把你自己这块材料铸造成器。
——胡适