Normalization (DK/NF) Anyone ?

I realize this may not be the appropriate forum to address my question. If you are offended please disregard this message. Otherwise see if you can help me out.

I have this problem I was given.

	There is a relation X (A,B,C,D,E)
	 With the following dependencies
	{A,B} --> C,D,E
	D --> A
	E --> B

Now I am trying to put this in DK normal Form. I am tempted to have these Five Relations relations,

	R1(A,D)		Key : D
	R2 (E,B)		Key : E
	R3 (A,B,C)		Key : {A,B}
	R4 (A,B,D)		Key : {A,B}
	R5 (A,B,E)		Key : {A,B}

But I realize there is a problem with R4 and R5, That is they are not in BCNF. This is the case, since D which is a determinant of A is can not be a candidate key.

Is there anyway I can transform this relation into DK/NF. Please send answers to my address (lk1j_at_andrew.cmu.edu) as well as the bboard.

Thank You Received on Mon Mar 02 1992 - 14:40:44 CET