输入：
drop table if exists `user_profile`;
drop table if  exists `question_practice_detail`;
CREATE TABLE `user_profile` (
`id` int NOT NULL,
`device_id` int NOT NULL,
`gender` varchar(14) NOT NULL,
`age` int ,
`university` varchar(32) NOT NULL,
`gpa` float,
`active_days_within_30` int ,
`question_cnt` int ,
`answer_cnt` int 
);
CREATE TABLE `question_practice_detail` (
`id` int NOT NULL,
`device_id` int NOT NULL,
`question_id`int NOT NULL,
`result` varchar(32) NOT NULL
);
INSERT INTO user_profile VALUES(1,2138,'male',21,'北京大学',3.4,7,2,12);
INSERT INTO user_profile VALUES(2,3214,'male',null,'复旦大学',4.0,15,5,25);
INSERT INTO user_profile VALUES(3,6543,'female',20,'北京大学',3.2,12,3,30);
INSERT INTO user_profile VALUES(4,2315,'female',23,'浙江大学',3.6,5,1,2);
INSERT INTO user_profile VALUES(5,5432,'male',25,'山东大学',3.8,20,15,70);
INSERT INTO user_profile VALUES(6,2131,'male',28,'山东大学',3.3,15,7,13);
INSERT INTO user_profile VALUES(7,4321,'male',28,'复旦大学',3.6,9,6,52);
INSERT INTO question_practice_detail VALUES(1,2138,111,'wrong');
INSERT INTO question_practice_detail VALUES(2,3214,112,'wrong');
INSERT INTO question_practice_detail VALUES(3,3214,113,'wrong');
INSERT INTO question_practice_detail VALUES(4,6543,111,'right');
INSERT INTO question_practice_detail VALUES(5,2315,115,'right');
INSERT INTO question_practice_detail VALUES(6,2315,116,'right');
INSERT INTO question_practice_detail VALUES(7,2315,117,'wrong');
INSERT INTO question_practice_detail VALUES(8,5432,118,'wrong');
INSERT INTO question_practice_detail VALUES(9,5432,112,'wrong');
INSERT INTO question_practice_detail VALUES(10,2131,114,'right');
INSERT INTO question_practice_detail VALUES(11,5432,113,'wrong');
输出：
2315|115|right
2315|116|right
2315|117|wrong

select
  q.device_id,
  q.question_id,
  q.result
from
  question_practice_detail q,
  user_profile u
where
  q.device_id = u.device_id
  and university = '浙江大学'
order by
  q.question_id asc

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

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 asc