Re: NULLs

On Sat, 5 Jan 2008 13:57:51 -0800 (PST), Marshall wrote:

>On Jan 5, 1:25 am, "Brian Selzer" <br..._at_selzer-software.com> wrote:
(snip)
>> I disagree. With nulls there is an explicit indication that there is
>> information that exists but hasn't been supplied. It is not a matter of
>> interpretation. Without nulls, there is no explicit indication so it
>> becomes a matter of interpretation.
>
>The interpretation you're supplying may well be the one
>*intended* by the designers of SQL

Hi Marshall,

It is not. Here is the interpretation *intended* by the designers of SQL, as specified in the SQL-2003 standard.

Source: ISO/IEC 9075-1:2003 (E)
"3.1.1.11 null value: A special value that is used to indicate the absence of any data value."

The absence of any data value. No more, no less.

Also note that this definition is almost identical to the wording used over 10 years prior, in SQL-92:

" r) null value (null): A special value, or mark, that is used to

     indicate the absence of any data value."

Best, Hugo Received on Tue Jan 08 2008 - 01:21:43 CET