SELECT stu.*
FROM student stu
    JOIN sc s ON stu.sno = s.sno
WHERE s.cno IN (
    SELECT cno
    FROM course
    WHERE course.tno = (
        SELECT tno
        FROM teacher
        WHERE teacher.tname = '張三'
    )
);

先查出上了張三老師的課的學生的編號。然后在用子鏈接查詢學生的信息。