Re: Thinking about MINUS

From: paul c <toledobythesea_at_oohay.ac>
Date: Sun, 07 Jan 2007 16:15:28 GMT
Message-ID: <A09oh.556343$1T2.163735@pd7urf2no>

Walt wrote:
...
> Either NOR or NAND are enough to bootstrap to the rest of it, provided you
> make one little extension to them:
>
> NOR or NAND with only one operand is NOT.
>
> I don't know where it leads regarding database, either. Just a random
> thought.

One of a couple of reasons this topic intrigues me is that certain scenarios aren't closed for operations in Codd's framework, eg., the case when two operands share an attribute name that has different types. I realize that a whole sub-industry has been built to deal with problems like this (based on various design disciplines, knowingly or unknowingly, I don't know), so many people would say I'm silly to wonder, but I can't help it.

p Received on Sun Jan 07 2007 - 10:15:28 CST