Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Usenet -> comp.databases.theory -> Re: completeness of the relational lattice

Re: completeness of the relational lattice

From: Vadim Tropashko <vadimtro_invalid_at_yahoo.com>
Date: Fri, 29 Jun 2007 09:20:18 -0700
Message-ID: <1183134018.947572.222310@o11g2000prd.googlegroups.com>


On Jun 28, 3:41 pm, Jan Hidders <hidd..._at_gmail.com> wrote:
> > > I invite you to challenge me to show that it can prove an equation
> > > that holds. Of course you should also check if all these equations can
> > > be derived by you.

One more challenge:

<xy> + S + Q = <xy> + S

where S * [] = [z], and Q header is unconstrained. (I don't see axioms about the lattice bottom element:-) Received on Fri Jun 29 2007 - 11:20:18 CDT

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US