Re: 3 value logic. Why is SQL so special?

From: peter koch <peter.koch.larsen_at_gmail.com>
Date: 19 Sep 2006 04:19:12 -0700
Message-ID: <1158664752.132356.46820@d34g2000cwd.googlegroups.com>

Bob Badour wrote:
> Chris Lim wrote:
>
> > Roy Hann wrote:
> >

[snip]

>
> Then why have I had to spend so much time in my career explaining to
> reasonably intelligent people why their queries returned the wrong answer?
>

[snip]

>
> I must insist you back up that statement quantitatively and
> qualitatively. It is far easier to deal with two names than with
> surprisingly inconsistent semantics for the same reason it is far easier
> to deal with a compile-time error than a run-time error.
>

[snip]

> But a
> > database without NULLs? It might be theorectically correct, but it
> > would be a nightmare to write queries against.
>
> I disagree. My personal experience dealing with scores of intelligent
> database users suggests that NULL is the nightmare.

All these arguments against NULL are only valid against some specific implementations of that concept - here SQL in its various dialects. They are not arguments against the concept of having null-values (e.g. to represent unknown values) in some database system. And this is comp.databases.theory after all.

/Peter Received on Tue Sep 19 2006 - 06:19:12 CDT