Re: Another view on analysis and ER

paul c schreef:
mAsterdam wrote:
paul c schreef:
mAsterdam wrote:
paul c schreef:
<Nomme, Ans>
<Name, Years>

are different headings.

Yes. However, having multiple headings in one relation
is not part of RM AFAIK. ...

Who said anything about multiple headings in one relation?

I did. It is the way I labelled:

>>> <Nomme, Ans>
>>> <Name, Years>

... appearantly not something you intended.
Why not - or, better: what are they?

Oh, it was you, was it? Whew, that was a close one. Maybe I misled with the tilted carets or whatever they're called and should have used braces, also by abbreviating them without type names, which seems common whenever the purpose isn't affected.

Explicit types do not reduce the number of headers.

Anyway, I suppose there might not be anything theoretically wrong with an rdbms that allowed multi-lingual headings, so that the Frenchman could pretend the db was using his lingo and the Englishman his, although they might get up to more hijinks whenever RENAME came into play than those two nationalities ever did in the last 900 years.

If you insist on such a thing, I hope you'll call them some kind of alias as I think there is already more than enough multi-lingual false correctness in the world.

Please do not attribute your invention to me just because
I labelled it.

This seems like a good place to completely re-quote your claim.

No need, the RM already is language-neutral, eg.,

<John,33>
<Johan,33>
<Jaan,33>

are different, not the same.

Same goes for headings:

<Nomme, Ans>
<Name, Years>

are different headings.

I read your example as having multiple headings to one relation -
which is outside the RM as I know it. You prefer to call them aliases?
If so: aliases of what?

As the Mott's Clamato man said, why stop there? Might as well have multi-lingual aliases for relation and relvar names too. What the heck, do similar for values in tuples.

Making the values in tuples language-neutral makes sense if the
people sharing the data do not share a language.

Exposure: Where I live most people have to learn at least
two foreign languages (English and one of French and German).

For a while, the effect might be drastically deleterious for update performance, but eventually an optimization theory might appear. So typical of the IT world to optimize the tool rather than the problem. The DB world being so over-endowed with clarity, I guess adding a good dose of obscurity can't hurt it either!

(Just my not too blunt way of doing my bit and helping us all yet again that explaining analysis and design is harder than doing it.)
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