Have questions on normalization....
Posted on 2004-10-16
Want to make sure I understand a question about normalization. I have read about and seem to understand it in my mind but a bit confused on question.
Choose a key and write the dependencies for the following relation:
GRADES (StudentID, Course#, Semester#,Grade)
In what normal form is this relation.
From what I understand above: I would need to have StudentID,Course#,Semsester ==>Grade
The first 3 have to be the composite key or the table would have duplicate data.
I know a student can retake a course (my own experience) and get a grade of "W" then have to take the course again but another semester.
1234, Course345, SemsesterFall2003, W
1234, Course345, SemsesterSpring2004, A
What is stupid about this excercise to me is:
1) THere is not student name here
2) no Course description
3) no Professor that teaches the course
Due to above I would assume GRADES is 1 relation of many wihtin larger database.
Thus GRADES with PRIMARY KEY: StudentID,Course#,Semsester
FUNCTIONAL DEPENDENCY OF GRADES ON THOSE = 3rd normal form.
Does this make sense Or am I really not getting it?