Re: So what's null then if it's not nothing?
Date: Sun, 20 Nov 2005 00:43:03 +0100
Message-ID: <ltdvn1dd5k2cdqthb9s5jjsihpgf9lvsdj_at_4ax.com>
On Sat, 19 Nov 2005 23:19:58 +0000, Bernard Peek wrote:
>In message <fn5sn19kcr7og6p8hjnodb7j67umo6tbu9_at_4ax.com>, Gene Wirchenko
Hi Bernard,
Almost there. Almost.
Does my dig exist? is a yes/no question. The answer to that is a boolean
value. And booleans are not defined as a data type in SQL. There's a
reason for that. All SQL data types can also accomodate a Null, but a
boolean can't. All yes/no questions can allways be answered. Not with
"yes" (true), "no" (false), or "no answer" (Null), but with "yes", "no",
or "don't know" (unknown).
A better example would be:
><genew_at_ucantrade.com.NOTHERE> writes
>
>> Does an object exist? If it does, we get the answer yes. If it
>>does not, we get the answer no. No NULL is needed.
>
>Does my dog exist?
What's the age (in whole years) of my dog?
Best, Hugo
-- (Remove _NO_ and _SPAM_ to get my e-mail address)Received on Sun Nov 20 2005 - 00:43:03 CET