Re: Functional dependency is multivalued dependency
From: Mikito Harakiri <mikharakiri_nospaum_at_yahoo.com>
Date: 30 Apr 2006 13:32:13 -0700
Message-ID: <1146429133.492051.169300_at_y43g2000cwc.googlegroups.com>
Date: 30 Apr 2006 13:32:13 -0700
Message-ID: <1146429133.492051.169300_at_y43g2000cwc.googlegroups.com>
Mikito Harakiri wrote:
> Clearly any furter progress has to leverage the laws around the two
> special relations that appear everywhere: equality and inequality
> relations. But what are the RA axioms that equality and inequality
> satisfy to? To begin with, I have trouble writing reflexivity, symmetry
> and transitivity for equality in RA terms...
Actually, even though there appeared no way to express reflexivity,
symmetry
and transitivity for equality relation in RL, there is one law that
equality must satisfy.
For any relation R(x,y,z)
(((R /\ `x=x1`) \/ `x1 y z`) /\ `x=x1`) \/ `x y z` = R
In other words renaming and renaming back should produce the same relation. Received on Sun Apr 30 2006 - 22:32:13 CEST