Re: Plea for help - Normalisation Problem
From: skotske <skotske_at_hotmail.com>
Date: Tue, 03 Dec 2002 23:19:10 +0000
Message-ID: <9_aH9.2897$8e2.1750_at_news-binary.blueyonder.co.uk>
>
>
> Here the repetition is that one CD may be borrowed multiple times. In your
> example, the repetition is that multiple CDs may be taken out in a single
> loan. Both are true.
>
> I don't know if this helps.
Date: Tue, 03 Dec 2002 23:19:10 +0000
Message-ID: <9_aH9.2897$8e2.1750_at_news-binary.blueyonder.co.uk>
David Cressey wrote:
> There is yet another way to change the unnormalised database to 1NF. The
> two relations would be
>
>
>>Loans(#LoanNo, #cdID, Surname, Telephone, E-mail, DateOut, DueBack) >>CDs( #cdID, Artist, Title, Label, DateBought)
>
>
> Here the repetition is that one CD may be borrowed multiple times. In your
> example, the repetition is that multiple CDs may be taken out in a single
> loan. Both are true.
>
> I don't know if this helps.
Yeah, thanks... things are becoming a bit clearer. But as I replied to the other response I'm still a bit confused as to how you know why the composite key is in the first relation?
K Received on Wed Dec 04 2002 - 00:19:10 CET