The correct query to retrieve names of students who do not have grade : SELECT Name FROM Students AS S WHERE S.ID NOT IN ( SELECT G.ID FROM Grades AS G); SELECT Name FROM Students AS S WHERE S.ID = ANY ( SELECT * FROM Grades AS G); SELECT Name FROM Students AS S WHERE S.ID SOME (SELECT * FROM Grades AS G); SELECT S.ID, G.CourseName FROM Students AS S WHERE EXISTS ( SELECT * FROM Grades AS G WHERE S.ID = G.ID)