Well, 0 is not nothing. That's why NULL made it into databases. I agree with
Richard here - if we renamed it to NOTHING or UNKNOWN, or better yet,
NO_VALUE, there could be far less confusion as to what it means. And it
perfectly makes sense to treat empty string as string with no value (hence,
NULL). Same as with a number with no digits (empty number, not 0). You
know it's a number, but don't have its value. You know it's a string, but don't
have its value. Problem (and source of confusion) here is that while number
with no digits is certainly a NULL, string with no characters is treated in most
languages as a special case of string - an empty string - and not as string with
no value. Most people easily accept ternary logic for numbers and dates
and just about any other data type, but they always try to apply binary logic
to strings even though they are working in a ternary logic environment and
advocate that since it is so in other languages/environments, it should also be
so in this environment just because they get used to the way it is elsewhere.
It's like dropping on Mars without a life support system and demanding that
air be as dense as on Earth because you used to be able to breathe without
any lss...
--
Vladimir Zakharychev (bob@dpsp-yes.com) http://www.dpsp-yes.com
Dynamic PSP(tm) - the first true RAD toolkit for Oracle-based internet applications.
All opinions are mine and do not necessarily go in line with those of my employer.
"Wolfram Roesler" <wr_at_grp.de> wrote in message news:Xns9272606BF7D48wrgrpde_at_62.153.159.134...
> ctcgag_at_hotmail.com wrote in news:20020821133838.353$Ug_at_newsreader.com:
>
> > I have a great idea, lets make numeric zero also be null. It worked
> > for the Romans.
>
> You perfectly got my point. '' is for strings what 0 is for integers.
> Remember how long it took mankind to accept the fact that it's
> useful to have a symbol for "nothing".
>
> Regards
> W. Roesler
Received on Thu Aug 22 2002 - 02:54:28 CDT
