Re: Getting Normal Forms *wrong*. Is there actual disagreement on what 1NF > 3NF means or is this sloppiness or ignorance on authors' parts?
Date: Fri, 7 Aug 2009 22:59:40 +0100
Message-ID: <HZ-dne_dBtxTPuHXnZ2dnUVZ8j-dnZ2d_at_giganews.com>
"Bob Badour" <bbadour_at_pei.sympatico.ca> wrote in message
news:4a7c6737$0$23786$9a566e8b_at_news.aliant.net...
>
>> Here's something I really need clarification on. Is it the case, or is
>> it *not* the case, that 2NF "only applies" in cases where there is a
>> composite key?
>
> It is the case.
>
Here's a relation:
Triangles {Id*, Area, SumOfAngles}
{}->{SumOfAngles}
{} (the empty set) is a proper subset of the key {Id} and {}->{SumOfAngles}
is a dependency on only part of the key. Triangles is a relation without a
-- David PortasReceived on Fri Aug 07 2009 - 23:59:40 CEST