Re: Examples of SQL anomalies?

From: goanna <spamtrap_at_crayne.org>
Date: Tue, 08 Jul 2008 11:41:31 GMT
Message-ID: <48735268$1@news.unimelb.edu.au>


Keith H Duggar <duggar_at_alum.mit.edu> writes:

> CELKO wrote :
> > Marshall wrote :
> > > False! It's not from nothing, and it's not simply a convention.
> > > It's the identity of the operator being aggregated. <<
> >
> > Yes, zero is the additive identity. But this is a convention used to
> > get rid of the empty set problem and preserve easy computations.

> Yes, sum[{}] = 1 eliminates problems and makes computation easier.
> It's a shame that SQL offers neither of those benefits.

I guess you mean sum[{}] = 0 Received on Tue Jul 08 2008 - 06:41:31 CDT

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