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

Damien wrote:

>
> Hi Mike,
>
> I'm by no means an expert. (Maybe I should stop there :-))
>
> Why do you view an empty string as being the same as null?

Because that's what NULL is.

> it certainly
> isn't in C/C++/C#.

It is in Pick. It is in Reality ;-)

> Try this for an example. You have a column for
> storing someones middle initial. I can think of three possible entries
> into that column:
>
> 1) Their middle initial.
> 2) An empty string - they do not have a middle name

Then this is, correctly, NULL.

> 3) NULL - we do not yet know anything about their middle initial

This is, correctly, UNKNOWN.

>
> So in that case, an empty string is definitely not the same as NULL.

It is unless you accept the erroneous definition of NULL as UNKNOWN.

> Hope this example might help you find a chink of light.
>
> Damien

It - and the remainder of this thread - has indeed clarified my thinking, thank-you. It is just a matter of people saying one thing and meaning another - again. Seems to be a recurring theme here. Funny that.

Cheers
Mike. Received on Fri Nov 18 2005 - 05:59:02 CET