How to select students that failed at least at all courses that student with id = 1 failed?

Question

I have the following tables:

STUDENT (student_id, first_name, last_name, birth_date, year , domain)

PROFESSOR (professor_id, first_name, last_name, birth_date, hire_date, title, salary)

COURSE (course_id, course_name, professor_id)

GRADE (student_id, course_id, grade, date_of_exam)

I have to display the students that failed at least at all the courses that student with id = 1 failed.

What I tried:

SELECT
s.student_id,
s.first_name,
s.last_name,
n.grade,
n.course_id
FROM
    student s
    JOIN grade n ON n.student_id = s.student_id
WHERE
    n.grade <= 4;

...this gets all the students that failed but I don't know how to go from this to all the students that failed at least at all the courses that student with id = 1 failed. If someone could point me in the right direction I would be grateful!

Additional details

For example: If student with id = 1 failed at courses with ids = 2,3. And we have other two students who failed at courses with ids = 2,3 (like student 1) and they might fail at other courses too, then I want to display those two students.

Answer 1

Here is one way of getting your desired results

SELECT *
FROM   STUDENT S
WHERE  NOT EXISTS (SELECT g1.course_id
                   FROM   GRADE g1
                   WHERE  g1.student_id = 1
                          AND g1.grade <= 4
                   MINUS
                   SELECT g2.course_id
                   FROM   GRADE g2
                   WHERE  g2.student_id = S.student_id
                          AND g2.grade <= 4) 

For each student it checks with MINUS whether there are any courses that student_id = 1 has failed that are not in the set of failed courses for the student under focus.

If there are no such courses then the NOT EXISTS evaluates to true and the student is returned.

student_id = 1 will be returned as they have obviously failed at least as many courses as themselves so you may want to filter that out.

Answer 2

If I get it right you want STUDENTS where it does not EXIST a COURSE that the STUDENT passed and STUDENT with id 1 failed:

SELECT student_id
FROM student s
WHERE student_id <> 1
  AND NOT EXISTS (
    SELECT 1 
    FROM GRADE g1
    JOIN GRADE g2
        ON g1.course_id = g2.course_id
    WHERE g1.student_id = 1
      AND g1.grade <= 4
      AND g2.student_id = s.student_id
      AND g2.grade > 4
);

I assumed grade > 4 means passed.

Answer 3

This should lump all the students who failed the same class together:

    with failboat as (select s.student_ID, c.course_id, g.Grade, 
    rank() over (partition by s.student_id order by date_of_exam) as failcount
    from STUDENT s
    inner join GRADE  on s.student_ID = g.student_ID
    inner join Course c on g.course_ID = c.course_ID
    where g.grade <=4)

    select f1.*, f2.*
    from failboat f1
    inner join failboat f2 on f1.courseID = f2.CourseID