Re: Distributivity in Tropashko's Lattice Algebra

Sorry,

I've made a mistake:

> Now, the novelty is that there is a *third* special element 00 the
> relation with with arity = 0 and cardinality = 0, which is not a unit
> in Relational Lattice. It is a mapper of a relation into a header
> relation!
>
> 00 join A = a

I wrote:

"Nope, '00' join A = A. It's no different from '01' join A"

It's different of course. '00' join A = 'a0'

Please ignore this:
"
N.B. You may define of course 'a' as '00' join A, but then the question is what is '00' ?
" Received on Tue Aug 16 2005 - 21:33:19 CEST