Re: what are keys and surrogates?
From: David Cressey <cressey73_at_verizon.net>
Date: Sun, 13 Jan 2008 21:41:50 GMT
Message-ID: <yAvij.2062$rV6.121_at_trndny06>
Date: Sun, 13 Jan 2008 21:41:50 GMT
Message-ID: <yAvij.2062$rV6.121_at_trndny06>
"David BL" <davidbl_at_iinet.net.au> wrote in message news:b05f3396-4c1f-4710-8d27-d4940b7e689f_at_e10g2000prf.googlegroups.com...
> This however doesn't change the fact that most authors define a
> (mathematical) relation as a set of ordered tuples, which means a
> function is not a relation (assuming, as most do, that a function has
> a defined domain and codomain).
I don't understand how the conclusion follow from the premise. Received on Sun Jan 13 2008 - 22:41:50 CET