Re: A question for Mr. Celko

From: Rene Hartmann <rhartmann_at_t-online.de>
Date: Tue, 20 Jul 2004 23:09:13 +0200
Message-ID: <Pine.LNX.4.33.0407202304550.1617-100000@linux.local>

On 18 Jul 2004, --CELKO-- wrote:

> The classic example for relation-valued columns is to put the table
> inside itself. Lazurus Long is his own great grandfather, if you are
> a Heinlein fan, and you fall into infinite recursion. A parts
> explosion suddenly has more assemblies than there are atoms in the
> Universe. I nest a table using the Ackermann function as my model
> (non-primitive recursion), Etc.
>

A table that contains itself can only appear if one allows recursive type definitions. If these are not allowed (and they shouldn't), relation-valued attributes have no problems of this kind.

--
Rene´ Hartmann

Received on Tue Jul 20 2004 - 16:09:13 CDT