Re: candidate keys in abstract parent relations

From: Gene Wirchenko <genew_at_ucantrade.com.NOTHERE>
Date: Fri, 20 Jan 2006 13:52:12 -0800
Message-ID: <2qm2t1ld9b91tnfg4958dlbi7ms49j24li@4ax.com>

On Fri, 20 Jan 2006 21:41:06 GMT, "David Cressey" <dcressey_at_verizon.net> wrote:

>"Forrest L Norvell" <spankysyourpal_at_gmail.com> wrote
>
>> Yes. This is where I've been blocked for several weeks now. I guess the
>> simplest way of stating it is, is there value to separating an Album
>> from a Release? Does it make sense to think about an Album as some sort
>> of Platonic ideal entity that exists independent from a release?
>>
>Just as an aside, what would an Album look like if there were no Releases on
>it?
>
>In other words, is the relationship between Albums and Releases mandatory
>(minimum cardinality 1)? I think this question is germane?
>
>What would a Release look like, if there were no related Album?

A single. Songs used to be released on 45s, one per side.

Sincerely,

Gene Wirchenko Received on Fri Jan 20 2006 - 15:52:12 CST