Re: Identifying transitive dependencies
Date: Tue, 07 Oct 2003 18:10:13 +0200
Message-ID: <3f82e525.0_at_news.ruca.ua.ac.be>
David wrote:
>
> I've first tried to find the functional dependencies (they may or may not be
> correct)
>
> * StudId -> Name
> * (StudId, CourseCode) -> Name, CourseDesc, Lecturer, Grade, Office
> * CourseCode -> CourseDesc, Lecturer, Office
> * CourseDesc -> CourseCode, Lecturer, Office
> * Lecturer -> CourseCode, CourseDesc, Office
As Alan already pointed out, it is a bit unlikely that every lecturere gives at most one course. Your list is also a bit redundant, but that doesn't make it incorrect.
> I then thought that (StudId, CourseCode) -> Office, CourseDesc, Lecturer
> might be a transitive dependency within student. Is it?
In order to know that you have to determine if (StudId, CourseCode) is a candidate key or not. (They did give you definition of what a transitive dependency is, didn't they?) Is it?
- Jan Hidders