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From: amado.alves@netcabo.pt
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Subject: Re: Nested Sets vs. Nested Intervals
Date: 10 Nov 2005 19:02:24 -0800
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Xref: dp-news.maxwell.syr.edu comp.databases.theory:34337

Mneson is not Codasyl nor OQL based on the descriptions I have of
those.

I believe the Mneson Calculus is an algebra. I'm still working on it.
Example laws:

T ({x1, x2, ...}) = T({x1}) U T({x2}) U ...
T ({}) = {}
T (XUY) = T(X) U T(Y)
T (X^Y) = T(X) ^ T(Y)
Etc.

Conditions on values are made possible by introducing value ranges, set
of values expressed in a compact way, typically as an interval or a
bound. Querying for employees earning less than 40,000:

T (Employees) ^ S (S (T (T (Salary)) ^ RangeForLessThan (40'000)))

Of course query optimization would kick in here, and that's the main
purpose of having the algebra.