Re: cdt

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"Laconic2" <laconic2_at_comcast.net> wrote in message news:3N-dnZ1utJaq7lnd4p2dnA_at_comcast.com...
> (re: "location")
> "Alan" <alan_at_erols.com> wrote in message
> news:2ij96jFnk21uU1_at_uni-berlin.de...
> > Not relevant to a logical model at all.
>
> Except when discussing the utility of a logical model in the context of a
> larger project.
>
> The fact that the RDM establishes relationships without pinning down
> locations is part of the reason why it has more data independence than
some
> other models. This is turn is one of the things that make the RDM a good
> candidate for logical modelling.
>
> I think that the term "access paths" in the Codd 1970 paper is related to
> what we often call "location". What do D&D have to say about "access
paths
> and or location"?

They say something like "a location is [a] variable, not [a] constant" .

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