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Home -> Community -> Usenet -> comp.databases.theory -> Re: equivalence of functional dependencies
"shannon" <shannon_at_nolunchmeat.com> wrote in message
news:btcrsd$m1u$04$1_at_news.t-online.com...
> FD has been bugging me for a month now,
>
> F = {A -> BC, A -> D, CD -> E}
> G = {A -> BCE, A -> ABD, CD -> E}
>
> I have been told that the sets of functional dependencies above are
> equivalent, can anybody explain to me how I can come to this conclusion
> step by step,
>
> I understand that armstrong's axioms are used to come to the conclusion,
> I have seen these axioms written down,
>
> please use another example if you are in fear of doing 'homework'
As a general method, consider transforming each of the sets to some canonical form. Received on Tue Jan 06 2004 - 02:09:23 CST
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