Re: The "standard" way to get to 3NF
From: Jan Hidders <jan.hidders_at_REMOVETHIS.pandora.be>
Date: Sat, 10 Apr 2004 08:30:29 GMT
Message-ID: <FgOdc.66173$337.4619398_at_phobos.telenet-ops.be>
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> You've lost E - was that a mistake in the FD's or in the example relation?
Date: Sat, 10 Apr 2004 08:30:29 GMT
Message-ID: <FgOdc.66173$337.4619398_at_phobos.telenet-ops.be>
Jonathan Leffler wrote:
> 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 >> >> >> Did anyone notice that this algorithm is actually not correct? Take >> the following example of a relation R(A,B,C,D,E) with the set of FDs: >> >> { AB->C, AB->D, BC->D }
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> You've lost E - was that a mistake in the FD's or in the example relation?
Oops. That's a mistake in the example relation. Sorry about that.
- Jan Hidders