Re: Distributivity in Tropashko's Lattice Algebra

From: vc <boston103_at_hotmail.com>
Date: 17 Aug 2005 11:44:20 -0700
Message-ID: <1124304260.665596.73450_at_g47g2000cwa.googlegroups.com>


Mikito Harakiri wrote:
> VC wrote:
> > "Mikito Harakiri" <mikharakiri_nospaum_at_yahoo.com> wrote in message
> > news:1124225375.601615.162210_at_g47g2000cwa.googlegroups.com...
> > >
> > > vc wrote:
> > >> A union '00' = '00'.

Sorry, I meant A union '00' = '01', of course. Was confused by your unorthodox union.

> There is another argument against
>
> A union 00 = 00
>
> For any two relations A and B, the relation
>
> A union B
>
> has cardinality bigger than both A and B. In you proposition this
> property is lost.

Right. See above.

To sum up, the three '1' '0' combinations are :

00 union A = 01
00 join A = 'a0' where 'a' is A's set of attrs.

01 union A = 01
01 join A = A

10 union A = A
10 join A = 10 Received on Wed Aug 17 2005 - 20:44:20 CEST

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