Re: SUPPORT FOR DECLARATIVE TRANSITION CONSTRAINTS

On Sep 22, 12:46 pm, paul c <toledobythe..._at_oohay.ac> wrote:
> On 22/09/2010 6:52 AM, Brian wrote:
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> > On Sep 22, 7:10 am, Erwin<e.sm..._at_myonline.be>  wrote:
> >> On 22 sep, 03:31, Brian<br..._at_selzer-software.com>  wrote:
> ...
> >>> Constraints are a matter of semantics--that is, what the data means.
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> >> And what the data means is the logical conjunction of the propositions
> >> that the tuples represent, or in my abstract example, "P(t1) AND
> >> P(t2)", and "P(t3) AND P(t4)", respectively, and this regardless of
> >> what the P() is.
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> >> Nothing less, and most certainly nothing more.  And I do not need to
> >> specify the predicate for that claim to be true.
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> >> Meaning that the transition itself, is not part of the semantics of
> >> the database.  Meaning that transition constraints are, contrary to
> >> what you claim, NOT about semantics.  And therefore NOT about business
> >> rules either.
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> >> Also meaning that if you have one possible transition from "P(t1) AND
> >> P(t2)" to "P(t3) AND P(t4)" that gets rejected, and another one from
> >> "P(t1) AND P(t2)" to "P(t3) AND P(t4)" that gets accepted, then that
> >> means that your model is driven by something more than merely
> >> semantics, and that in turn means that your model is flawed.- Hide quoted text -
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> >> - Show quoted text -
> > ... Your argument above is lacking because it
> > doesn't take into account that since P(t1) and P(t3) were judged to be
> > true at different times, P(t1) and P(t3) can mean the same thing at
> > different times, or different things at different times.  ...
>
> Heh, here we go again, more attacking mutant tuples, but thanks for a
> great example of undersimplification.  A database where two different
> propositions mean the same thing (no matter whether at the same time or
> at different times) is seriously nonsensical, likely laughable even to a
> layman, possibly dangerously unmaintainable and certainly over-priced.
> Redundant, anyone?- Hide quoted text -
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> - Show quoted text -

The tuples don't belong to the same database. Duh! Received on Wed Sep 22 2010 - 19:33:06 CEST