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Schema Modification Exercise 1


Notes:

The first new constraint is the fd tnr->coursename in the relation teaches. This relation is no longer in BCNF. Decomposition results in
teaches_1(tnr, coursename) teaches_2(tnr, grade)
Note that the constraint has no influence on the relation qualification.
The second constraint is an mvd. Since the question is to ensure BCNF only we can ignore it.
If we were to use it we would decompose the qualification table into
qualification_1(tnr, coursename) qualification_2(tnr, grade)