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Home -> Community -> Usenet -> comp.databases.theory -> Re: The "standard" way to get to 3NF
Jan Hidders wrote:
> Jan Hidders wrote:
>> [...] The usual algorithm that gets you to 3NF in one step (the one >> using the minimal cover) splits as little as possible. See for example >> sheet 46 on: >> >> http://cs.ulb.ac.be/cours/info364/relnormnotes.pdf
As was pointed out to me by Ramez Elmasri, the counterexample is not correct since the set of FDs is not a minimal cover. The reason for this is that AB->D can be derived from AB->C and BC->D. So a proper minimal cover would be
{ AB->C, BC->D }
and that leads to the decomposition
{ ABC, BCD } which is indeed in 3NF.
I now officially declare this thread closed an will stop replying to myself. :-)