Question

This is a question I could not answer in oracle lab exam.

Given the schema:

(Courses: cid(int), deptid(int)...);
(Students: sid(int), sname (string), deptid(int)...);
(Participation: cid(int), sid(int), ...);

A student can attend courses outside his department.

Need to get the names of the students who take all the courses offered by his department.

How to do this in sqlplus?

Answer 1

SELECT s.sid, s.sname, s.deptid
    FROM Students s
        INNER JOIN Participation p
            ON s.sid = p.sid
        INNER JOIN Courses c
            ON p.cid = c.cid
                AND s.deptid = c.deptid
    GROUP BY s.sid, s.sname, s.deptid
    HAVING COUNT(DISTINCT c.cid) = (SELECT COUNT(*)
                                        FROM Courses c2
                                        WHERE c2.deptid = s.deptid)