Re: How to find Brothers and Sisters?
Date: Wed, 10 Jan 2007 15:15:24 GMT
Message-ID: <gq7ph.43088$cz.630874_at_ursa-nb00s0.nbnet.nb.ca>
Tonkuma wrote:
> --CELKO-- wrote: >
>>>>, I do not recall that Codd's original specification of 1NF allowed NULL. <<
>>
>>Yep, right from the start in RM1 as rule #3:
Joe wouldn't know RM1 if it bit him on the ass. Codd's original specification of 1NF appeared in his 1969 and 1970 papers and had absolutely nothing to do with the 12 rules some vendor paid him to publish.
Joe is living proof that, if one cannot dazzle with brilliance, one can always baffle with bullshit instead.
>>3. Systematic treatment of null values
>>
>>The DBMS is required to support a representation of "missing
>>information and inapplicable information" that is systematic, distinct
>>from all regular values (for example, "distinct from zero or any other
>>number," in the case of numeric values), and independent of data type.
>>It is also implied that such representations must be manipulated by the
>>DBMS in a systematic way
>
> I agree CELCO (If I undestood rightly his wrote information).
[snip]
> More over, thers is a possibility SALARY is UNKNOWN. But it is KNOWN > that it is already PAID or not.
Judge: "Why didn't you pay the plaintiff?"
Defendant: "We did pay the plaintiff."
Judge: "Really? How much did you pay the plaintiff?"
Defendant: "We don't know, but we know we paid him."
Oh yeah, that'll stand up in court. ::rolls eyes:: Received on Wed Jan 10 2007 - 16:15:24 CET