Re: How to normalize this?
From: Erwin <e.smout_at_myonline.be>
Date: Mon, 6 May 2013 12:48:10 -0700 (PDT)
Message-ID: <9d3b9fa9-16df-4d76-8f33-6a9f42be4b16_at_googlegroups.com>
Date: Mon, 6 May 2013 12:48:10 -0700 (PDT)
Message-ID: <9d3b9fa9-16df-4d76-8f33-6a9f42be4b16_at_googlegroups.com>
Op maandag 6 mei 2013 21:27:19 UTC+2 schreef Erwin het volgende:
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> If C->B applies, then how is R1 in 3NF ?
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> Looking at the relation schema for R1, sole candidate key is AB. The applicable FD's LHS is completely outside the candidate key.
Of course, if C->B effectively applies, then AB is no longer really the sole candidate key, since AC is a candidate key too, but even so the FD at hand "starts from" a proper subset of a candidate key, meaning it's not even 2NF (if I recall my NF's correctly. I have to use a "donkey bridge" to remember. The key, the whole key, and nothing but the key. "whole key"=2, "nothing but the key"=3.) Received on Mon May 06 2013 - 21:48:10 CEST