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Re: So what's null then if it's not nothing?

From: David Cressey <david.cressey_at_earthlink.net>
Date: Sat, 26 Nov 2005 04:00:02 GMT
Message-ID: <65Rhf.5385$N45.4440@newsread1.news.atl.earthlink.net>

"Jon Heggland" <heggland_at_idi.ntnu.no> wrote in message news:MPG.1df1305d7cd63f9998970d_at_news.ntnu.no...

> My question is this:
>
> You say the empty string is the same as "no value at all", and say we
> should call this concept of "no value at all" NULL for other data types.
> Now, the empty string is a perfectly normal string. You can do string
> operations on it: concatenate it, find its substring, find its length
> and so on. For an integer variable that is NULL, it is very different.
> You cannot do integer operations on it; you cannot add it to another
> integer, or multiply it, for example.

As I comented a couple of weeks ago,

A || EMPTY == EMPTY || A == A for every string A

That makes EMPTY a pretty interesting string, from my point of view. I wouldn't want to confuse it with NULL any more than I'd want to confuse the integer zero with NULL.

 My comment drew no response. I'm not about to draw any inferences from that absence of a response. Received on Fri Nov 25 2005 - 22:00:02 CST

Original text of this message

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