题解 | #浙江大学用户题目回答情况#
浙江大学用户题目回答情况
https://www.nowcoder.com/practice/55f3d94c3f4d47b69833b335867c06c1
select q.device_id,q.question_id,q.result
from question_practice_detail as q,user_profile as u
from question_practice_detail as q,user_profile as u
where u.device_id=q.device_id and university='浙江大学';
连接查询,先把表连接,再添加筛选条件,最后弄筛选项。
筛选项中注意是哪个表的!!!!