Fabian Pascal posts (LinkedIn, Data Modeling, 2020/03/29)
Shown a data model diagram, he says "Actually, it is not a logical model, but a graphical representation of it that users understand -- the DBMS doesn't. Users understand the conceptual model SEMANTICALLY, the DBMS "understands" the true logical model ALGORITHMICALLY and that's not what your drawing is.
Everest responds:
Regarding model (re)presentation, the exact same model can be presented in a variety of ways - graphical diagram, formal linear (for machine processing, I take you call this "logical"). But I would hope and expect that the underlying semantics would be exactly the same. We build a data model, and it should not matter how it is expressed, as long as they are equivalent. The semantics relate to the model, not how it is expressed (Conceptual?). Semantics is the meaning behind what is presented. Furthermore, all models are logical, that is, built according to some set of rules of logic and formal argument, no matter how it is presented or who reads it (check your dictionary). The rules in this case constitute what I call the modeling scheme.
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