Re: Examples of SQL anomalies?
Date: Fri, 04 Jul 2008 18:44:35 GMT
"Bob Badour" <bbadour_at_pei.sympatico.ca> wrote in message
> David Cressey wrote:
> > "Brian Selzer" <brian_at_selzer-software.com> wrote in message
> > news:nFD9k.5753$LG4.2422_at_nlpi065.nbdc.sbc.com...
> >>"-CELKO-" <jcelko212_at_earthlink.net> wrote in message
> >>>>>The question is, if these issues are due to the SQL specification or
> >>>>>simply due to a problem in a specific SQL product. Or could it be,
> > that
> >>>>>the definition is not precise enough in some points, so that database
> >>>>>vendors implemented it differently? <<
> >>>Nope, it is the specs. All aggregate (set) functions begin by
> >>>removing the NULLs from their parameter set, then if there is a
> >>>DISTINCT option on the parameter, they remove redundant duplicates and
> >>>finally do the operation (MIN, MAX, AVG, SUM, COUNT on what is left.
> >>>Since an empty set has no elements upon which to apply an operation,
> >>>SQL returns a NULL (okay, it should be an "undefined" if we were
> >>>mathematically correct).
> >>MIN, MAX and AVG are meaningless when applied to an empty bag, but it
> Bullshit! The identity element for min is the largest representable
> value. The identity element for max is the smallest representable element.
Unless I'm mistaken, you're attributing to me something written by Brian. I have trouble enough taking responsibility for my onw BS. I don't need to have other people's BS charged against me! Received on Fri Jul 04 2008 - 20:44:35 CEST