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Re: Nested Sets vs. Nested Intervals

From: <amado.alves_at_netcabo.pt>
Date: 10 Nov 2005 16:07:56 -0800
Message-ID: <1131667676.280790.90400@g47g2000cwa.googlegroups.com>


Each single concept is represented by a vertex. The properties of the concept are represented by topologies involving the vertex. The fact that employee x10 works in the accounting department may be modelled as

Employees => x10
x10 => x11
WorksIn => x11
x11 => Accounting

where x => y means connected from x to y. Note that this model makes similarly possible and simple to query for where does x10 work

T (T (x10) ^ T (WorksIn))

and for all workers in accounting

T (Employees) ^ S [S (Accounting) ^ T (WorksIn)]

(A more demanding schema would require a department be also a pivot, so it could have attributes attached, and be a member of a Departments like employee x10 is a member of Employees.) Received on Thu Nov 10 2005 - 18:07:56 CST

Original text of this message

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