Re: 1GB Tables as Classes, or Tables as Types, and all that refuted

From: Ja Lar <ingen_at_mail.her>
Date: Wed, 24 Nov 2004 21:07:08 +0100
Message-ID: <41a4e9f6$0$259$edfadb0f@dread11.news.tele.dk>

"Alfredo Novoa" <alfredo_at_ncs.es> ...

>>But the set of values that a relation is ("contains") cannot be mapped to
>>the set of values that a type is ("contains")
>
> They can be mapped but then you are not mapping a relation to a type,
> you are mapping the values contained in the tuples of a relation to
> the values of a type. This is a value to value mapping.

A "value to value mapping" in contrast to ...?

By what measure is that not a mapping from the relation (the set of values) to the type (the set of values) ?
I presume that we agree that a relation is a subset of the product set of the domains, and that the tuples are the elements in this set.

>>, ie. "a relation cannot be a
>>type", if I understand you right ?
>
> This is true, but this is not the same as you said above.
By what measure does this equivalence not follow from the mapping? Received on Wed Nov 24 2004 - 14:07:08 CST