Re: Questions on possreps
From: Bob Badour <bob_at_badour.net>
Date: Fri, 27 May 2011 09:09:26 -0700
Message-ID: <LtudnSifS9MwUULQnZ2dnUVZ5vOdnZ2d_at_giganews.com>
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> Sorry, I somehow managed to look at "why would anyone do that?" and
> saw "why would anyone define an uncountable type", and then forget how
> I actually posed my question.
>
> Ok, we agree there is no reason to outlaw uncountably infinite types.
>
> BTW I'm sure I've read posts on this group that suggest uncountable
> types are inappropriate in database theory. I think Jan Hidders has
> made comments along those lines, defining "value of type" as something
> capable of finite representation (I hope I'm not misrepresenting what
> he's said).
Date: Fri, 27 May 2011 09:09:26 -0700
Message-ID: <LtudnSifS9MwUULQnZ2dnUVZ5vOdnZ2d_at_giganews.com>
David BL wrote:
> On May 27, 2:27 pm, David BL <davi..._at_iinet.net.au> wrote:
>
>>On May 27, 6:55 am, Eric <e..._at_deptj.eu> wrote: >> >> >>>On 2011-05-26, David BL <davi..._at_iinet.net.au> wrote:
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>>>>16) Does Date outlaw types which are uncountably infinite (because >>>>there is no representation with a finite encoding for every value)? >> >>>Of course not, why would anyone do that? >> >>I would! The reals are clearly the most appropriate abstraction of >>numbers in computational geometry applications.
>
>
> Sorry, I somehow managed to look at "why would anyone do that?" and
> saw "why would anyone define an uncountable type", and then forget how
> I actually posed my question.
>
> Ok, we agree there is no reason to outlaw uncountably infinite types.
>
> BTW I'm sure I've read posts on this group that suggest uncountable
> types are inappropriate in database theory. I think Jan Hidders has
> made comments along those lines, defining "value of type" as something
> capable of finite representation (I hope I'm not misrepresenting what
> he's said).
You may be referring to the work Date, Darwen and Lorentzos did on temporal databases and interval type generators. They made the pragmatic decision to base their work on closed intervals over discrete, finite, total orders.
Or you may be referring to instances where I observed how daft Joe is for objecting to finite database operations on the basis of paradoxes applying only to infinite sets. Received on Fri May 27 2011 - 18:09:26 CEST