SELECT * FROM Student_1 S1 WHERE NOT EXISTS (SELECT * FROM Student_2 S2 WHERE S1.name = S2.name AND S1.age = S2.age AND S1.score = S2.score ) UNION ALL SELECT * FROM STUDENT_2 S2 WHERE NOT EXISTS (SELECT * FROM STUDENT_1 S1 WHERE S1.name = S2.name AND S1.age = S2.age AND S1.score = S2.score );