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BCNF vs. 3NF?

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Kurgan
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09 Feb 2013, 12:33 pm

Can anyone please give a simple explanation? :)



naturalplastic
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09 Feb 2013, 4:55 pm

NFZ2MCH

Thats what I say!



Utnapishtim
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09 Feb 2013, 5:48 pm

Third normal form
Every non-prime attribute is non-transitively dependent on every candidate key in the table. The attributes that do not contribute to the description of the primary key are removed from the table. In other words, no transitive dependency is allowed.

Boyce–Codd normal form
Every non-trivial functional dependency in the table is a dependency on a superkey.

Multiple overlapping candidate keys is the difference between the two normal forms.
Also to note a table in BCNF can also be in 3NF as well.