2nd Normal Form Question

#81

"paul c" <toledobythesea (AT) oohay (DOT) ac> wrote

Quote:

David Portas wrote:
...
Here's a counter example. PatientId is the candidate key but the relation
is not in 2NF. This is an unusual case but I don't think it should be
ignored.

Pregnancies {PatientId, Gender, DueDate}

FDs:
{PatientId} -> {DueDate}
{} -> {Gender}

If you have {} -> {Gender} don't you also have {PatiendId} -> {Gender,
DueDate} ?

Yes.

--
David Portas

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2nd Normal Form Question

comp.databases.theory comp.databases.theory

Re: 2nd Normal Form Question - 02-08-2008 , 04:48 PM