Consider the set of relations shown below and the SQL query that follows: Students: (Roll_number, Name, Data_of_birth) Courses: (Course number, Course_name, Instructor) Grades: (Roll_number, Course_number, Grade) Select distinct Name from Students, Courses, Grades where Students. Roll_number = Grades Roll_number and Grades.grade and courses. Instructor = korth and Courses.course - number = Grades.course - number Roll_number = Grades.Roll_number and Grades.grade = A Which of the following sets is computed by the above query?

Names of students who have got an A grade in all courses taught by Korth

Names of students who have got an A grade in all courses

Names of students who have got an A grade in at least one of the courses taught by Korth

Consider the set of relations shown below and the SQL query that follo

1.	Consider the set of relations shown below and the SQL query that follows: Students: (Roll_number, Name, Data_of_birth) Courses: (Course number, Course_name, Instructor) Grades: (Roll_number, Course_number, Grade) Select distinct Name from Students, Courses, Grades where Students. Roll_number = Grades Roll_number and Grades.grade and courses. Instructor = korth and Courses.course - number = Grades.course - number Roll_number = Grades.Roll_number and Grades.grade = A Which of the following sets is computed by the above query?
A.	Names of students who have got an A grade in all courses taught by Korth
B.	Names of students who have got an A grade in all courses
C.	Names of students who have got an A grade in at least one of the courses taught by Korth
D.	None of the above
Answer» D. None of the above

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