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Re: Basic question?What 's the key if there 's no FD(Functional Dependencies)?

From: vldm10 <vldm10_at_yahoo.com>
Date: 1 Nov 2006 09:44:58 -0800
Message-ID: <1162403098.627006.128180_at_i42g2000cwa.googlegroups.com> 






saturnlee_at_yahoo.com wrote:


> What 's the key for it? ABC or nothing???






ABC is not the key.


Example: Let one partricular entity has A,B,C atributes
and let these atributes take the following values:



    A        B         C



    2        4          6
    8        4          6
    2        4          6





( ABC  can be the key only in the trivial cases i.e if an entity has
the atributes whose values never change)
Received on Wed Nov 01 2006 - 18:44:58 CET












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