Re: Extending my question. Was: The relational model and relational

In message <7Ik5a.164$8e.17186852_at_mantis.golden.net>, Bob Badour <bbadour_at_golden.net> writes

>It's interesting how you are trying to mischaracterize Date as using
>primitive technology. Multisets are demonstrably more primitive than
>relations--simply from the fact that they rely on physical location. You are
>the one promoting the use of "Roman numerals and shells".

Multisets may rely on physical location, although that's a special case. The general case is that they rely on information outside the database to distinguish different items. If that happens to be physical location then you can add the current latitude, longitude and altitude as a key. There are some practical problems but in theory it's possible. In practise if you need to distinguish two cans of tuna you create an identity field, call it "Can Number" and print labels to stick on each can.

-- 
Bernard Peek
bap_at_shrdlu.com
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