Re: One-To-One Relationships

On Nov 28, 10:37 pm, paul c <toledobythe..._at_ooyah.ac> wrote:
> Bob Badour wrote:
> > rpost wrote:
> ...
> >> This is the exact problem Chen identified. In the relational model
> >> it is impossible to have entity-valued attributes, which, in practice,
> >> we have a huge amount of.
>
> > Entities are figments of our imaginations.
> > ...
>
> That's much better than my reply, looks like the essential point to me.

Entities are concepts that we impose on that which is there (mostly shapes made out of atoms, but sometimes abstractions too).

Entities are 'real' in that they are patterns that we think up and apply, and 'not real' in that if we were all dead, well there wouldn't be any 'entities' would there. Just atoms again.

Because we conjure them up 'entities' aren't neatly defined, can overlap, change, and will differ from person to person. In fact its a testament to the amazing flexibilty of our noggins that that we manage to communicate at all.

And as such, anyone who tells you that you can build a permanent, all encompassing model out of such utterly woolly things is not to be trusted as far as you can throw them.

P.S I have also had similar experinces at Ikea :) I don't follow the arrows anymore. They lie. Received on Thu Nov 29 2007 - 23:34:20 CET