Re: The Practical Benefits of the Relational Model
From: Lauri Pietarinen <lauri.pietarinen_at_atbusiness.com>
Date: 16 Oct 2002 14:45:46 -0700
Message-ID: <e9d83568.0210161345.6776840b_at_posting.google.com>
Date: 16 Oct 2002 14:45:46 -0700
Message-ID: <e9d83568.0210161345.6776840b_at_posting.google.com>
> Out of interest, how does D4 insert into this view?
>
> (A UNION B) MINUS (A INTERSECT B)
>
> It seems to me to be entirely arbitrary to insert into A rather than B, or
> vis-versa, and only slightly less arbitrary to not allow any inserts at
> all.
The latest article in www.dbdebunk.com (By Date and McGovern)
might shed light to that problem.
They state that it is a bad idea to have tables whose
On the other hand C says that their meaning does not overlap so hence the contradiction and the refusal of D4 to insert anything anywhere.
Lauri Received on Wed Oct 16 2002 - 23:45:46 CEST