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| <?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="studentMapper">
<!-- 定义封装resultMap
property 实体中对应的属性
column 数据库对应的列（select查询返回的列表）
-->
<resultMap type="xyz.shi.domain.Student" id="StudentGradeResult">
<id column="sid" jdbcType="BIGINT" property="id" />
<result column="sname" jdbcType="VARCHAR" property="name" />
<!-- 多对一关系的时候，多方使用association标签映射一方-->
<!-- <association property="grade" resultMap="StudentResult"></association>-->
<association property="grade" javaType="xyz.shi.domain.Grade">
<id column="gid" property="id" />
<result column="gname" property="name" />
</association>
</resultMap>
<resultMap type="xyz.shi.domain.Student" id="StudentCourseResult">
<id column="sid" jdbcType="BIGINT" property="id" />
<result column="sname" jdbcType="VARCHAR" property="name" />
<!-- 一对多 -->
<collection property="courses" ofType="xyz.shi.domain.Course">
<id property="id" column="cid"/>
<result property="name" column="cname"/>
</collection>
</resultMap>
<select id="queryOne" parameterType="int" resultMap="StudentCourseResult">
select s.name as sname,g.name as gname, g.id as gid, s.id as sid from student s,grade g where g.id = s.gid and s.id=#{id}
</select>
<select id="findAllStuCourse" resultMap="StudentCourseResult">
SELECT c.name as cname, c.id as cid, s.id as sid, s.name as sname
FROM student s
INNER JOIN student_course sc ON s.id = sc.student_id
INNER JOIN course c ON sc.course_id = c.id
</select>
<insert id="insertStudent" parameterType="xyz.shi.domain.Student"
useGeneratedKeys="true" keyProperty="id">
INSERT INTO student (name, gid) VALUES (#{name}, #{grade.id})
</insert>
<!---学生关联多个课程 -->
<insert id="batchInsertStudentCourse">
INSERT INTO student_course (student_id, course_id)
VALUES
<foreach collection="courseIds" item="courseId" separator=",">
(#{studentId}, #{courseId})
</foreach>
</insert>
<update id="updateStudent" parameterType="Student">
UPDATE student
SET name = #{name}
WHERE id = #{id}
</update>
<update id="updateStudentCourse" parameterType="java.util.Map">
UPDATE student SET name = #{student.name} WHERE id = #{student.id};
<!-- 先清空关联关系，然后重写插入 -->
DELETE FROM student_course WHERE student_id = #{student.id};
<foreach collection="courseIds" item="courseId" separator=";">
INSERT INTO student_course (student_id, course_id) VALUES (#{student.id}, #{courseId})
</foreach>
</update>
<delete id="deleteStudentAndRelations" parameterType="int">
DELETE FROM student WHERE id = #{id};
DELETE FROM student_course WHERE student_id = #{id};
</delete>
</mapper>
|