优化sql

cooleshow-user/user-biz/src/main/resources/config/mybatis/CourseScheduleStudentPaymentMapper.xml

@@ -45,7 +45,7 @@
     </select>
 
     <select id="queryStudentInfoByGroupId" resultType="com.yonge.cooleshow.biz.dal.vo.LiveCourseInfoVo$CourseBuyStudentVo">
-        select a.user_id_      as studentId,
+        select distinct a.user_id_      as studentId,
                b.real_name_    as studentName,
                b.avatar_ as avatar,
                a.created_time_ as createTime