Re: teaching relational basics to people, questions

From: rpost <rpost_at_pcwin518.campus.tue.nl>
Date: Fri, 20 Nov 2009 20:18:56 +0000 (UTC)
Message-ID: <he6tjg$tlg$1_at_mud.stack.nl>



Sampo Syreeni wrote:

>To me it would seem much more natural to model time as a full
>continuum of precise moments in time, and to constrain such real life
>models using a finite (but otherwise unlimited cardinality) set of
>FOPL constraints, relying on the full linear order on top of the
>reals, on top. I.e. to model time using CW-complexes over the real
>line (i.e. finite unions of open, closed and semi-closed intervals of
>reals), in a fully discrete but also fully variable precision
>approximation.

Doesn't this make it a bit hard to predict how long queries on time-valued domains may take? The amount of time required for manipulating a value will greatly vary. My guess is that why Date and Darwen rule it out for this reason. Then again, Date defines the use of essentially arbitrary domains elsewhere.

-- 
Reinier
Received on Fri Nov 20 2009 - 14:18:56 CST

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