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Exercise 17:1412.Find the Quiet Students in All Exams

1.Description

Table: Student
+---------------------+---------+
| Column Name | Type |
+---------------------+---------+
| student_id | int |
| student_name | varchar |
+---------------------+---------+
student_id is the primary key for this table.
student_name is the name of the student.
Table: Exam
+---------------+---------+
| Column Name | Type |
+---------------+---------+
| exam_id | int |
| student_id | int |
| score | int |
+---------------+---------+
(exam_id, student_id) is the primary key for this table.
Student with student_id got score points in exam with id exam_id.
A “quite” student is the one who took at least one exam and didn’t score neither the high score nor the low score.
Write an SQL query to report the students (studentid, studentname) being “quiet” in ALL exams.
Don’t return the student who has never taken any exam. Return the result table ordered by student_id.
The query result format is in the following example.
Student table:
+-------------+---------------+
| student_id | student_name |
+-------------+---------------+
| 1 | Daniel |
| 2 | Jade |
| 3 | Stella |
| 4 | Jonathan |
| 5 | Will |
+-------------+---------------+
​
Exam table:
+------------+--------------+-----------+
| exam_id | student_id | score |
+------------+--------------+-----------+
| 10 | 1 | 70 |
| 10 | 2 | 80 |
| 10 | 3 | 90 |
| 20 | 1 | 80 |
| 30 | 1 | 70 |
| 30 | 3 | 80 |
| 30 | 4 | 90 |
| 40 | 1 | 60 |
| 40 | 2 | 70 |
| 40 | 4 | 80 |
+------------+--------------+-----------+
​
Result table:
+-------------+---------------+
| student_id | student_name |
+-------------+---------------+
| 2 | Jade |
+-------------+---------------+
​
For exam 1: Student 1 and 3 hold the lowest and high score respectively.
For exam 2: Student 1 hold both highest and lowest score.
For exam 3 and 4: Studnet 1 and 4 hold the lowest and high score respectively.
Student 2 and 5 have never got the highest or lowest in any of the exam.
Since student 5 is not taking any exam, he is excluded from the result.
So, we only return the information of Student 2.

2.Create Table and insert into values

create table if not exists leetcode.ex_1412_student
(student_id string, student_name string) stored as orc ;
​
INSERT INTO table leetcode.ex_1412_student VALUES
('1','Daniel'),
('2','Jade'),
('3','Stella'),
('4','Jonathan'),
('5','Will')
;
​
create table if not exists leetcode.ex_1412_exam
(exam_id string, student_id string, score int) stored as orc ;
​
INSERT INTO table leetcode.ex_1412_exam VALUES
('10','1','70'),
('10','2','80'),
('10','3','90'),
('20','1','80'),
('30','1','70'),
('30','3','80'),
('30','4','90'),
('40','1','60'),
('40','2','70'),
('40','4','80')
;
“quite” student didn’t score neither the high score nor the low score.
It's meams for each exam, we must find those students whose sort by scores are not equal to 1 in either ascending and descending.
​