xiexie

SELECT * FROM user WHERE fk_class_id IN ("1,2") ;  // 3条数据，少了2班的1条数据

SELECT * FROM user WHERE fk_class_id IN (1,2) ; // 不带引号，正常4条数据

SELECT * FROM user WHERE FIND_IN_SET(fk_class_id,"1,2"); // 使用FIND_IN_SET 代替 IN ，正常4条数据

SELECT
  eu.id,
  eu.name,
  eu.skill,
  (SELECT GROUP_CONCAT(l.lottery_name) FROM bbx_lottery l WHERE FIND_IN_SET(l.lottery, eu.skill)) lotteryNames,
  eu.feedback,
  eu.passed,
  eu.up_type upType,
  eu.add_time addTime
FROM bbx_expert_up eu
<where>
  eu.user_id = #{userId}
  ORDER BY eu.add_time DESC
</where>