Вложенный запрос из 2х простых запросов

--выбираем число оценок у каждого студента   
SELECT Students.LastName, COUNT(Marks.Mark) AS AmountOfMarks 
FROM Marks INNER JOIN  
         Students ON Marks.StudentBookID = Students.NumberStudentBook
GROUP BY LastName

--выбираем число пятерок у каждого студента  
SELECT Students.LastName, COUNT(Marks.Mark) AS AmountOfFives
FROM Marks INNER JOIN
      Students ON Marks.StudentBookID = Students.NumberStudentBook
WHERE Mark = '5'  
GROUP BY LastName

SELECT Students.LastName 
FROM Students 
WHERE Students.NumberStudentBook NOT IN (
SELECT DISTINCT Marks.StudentBookID FROM Marks WHERE Marks.Mark <> '5')

--СПИСОК ОТЛИЧНИКОВ   
SELECT Students.LastName, COUNT(Marks.Mark)AS AmountOfMarks 
FROM Marks INNER JOIN  Students ON Marks.StudentBookID = Students.NumberStudentBook
GROUP BY LastName
HAVING COUNT(CASE WHEN Marks.Mark != 5 THEN 1 END) = 0

--СПИСОК ОТЛИЧНИКОВ   
SELECT LastName FROM Students s
WHERE EXISTS(SELECT * FROM Marks m WHERE m.StudentBookID=s.NumberStudentBook)
AND NOT EXISTS(SELECT * FROM Marks m WHERE m.StudentBookID=s.NumberStudentBook AND m.Mark!=5)

--СПИСОК ОТЛИЧНИКОВ  
SELECT s.LastName
FROM Students s
WHERE  (SELECT MIN(m.Mark) 
        FROM Marks m
        WHERE m.StudentBookID=s.NumberStudentBook)=5

--СПИСОК ОТЛИЧНИКОВ  
SELECT s.LastName
FROM Students s
WHERE (SELECT MIN(m.Mark) 
        FROM Marks m 
        WHERE m.StudentBookID=s.NumberStudentBook)=(SELECT MAX(Mark) FROM Marks)

--СПИСОК ОТЛИЧНИКОВ 
SELECT Students.LastName
FROM Marks INNER JOIN
      Students ON Marks.StudentBookID = Students.NumberStudentBook
GROUP BY LastName
HAVING MIN(Marks.Mark) = 5