题解 | 浙江大学用户题目回答情况

# select
# device_id
# ,question_id
# ,result
# from question_practice_detail
# where device_id in(
#     select device_id from user_profile
#     where university = '浙江大学'
# )
# order by question_id

select
q.device_id as device_id
,q.question_id as question_id
,q.result as result
from question_practice_detail q left join user_profile  u on q.device_id = u.device_id
where u.university = '浙江大学'
order by q.question_id

两个表连接in（）或者join on

需要通过device_id关联两个表的数据；