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<amado.alves_at_netcabo.pt> wrote in message
news:1131660473.524073.265700_at_g43g2000cwa.googlegroups.com...
> "Do you mean to say that the entity is presented as a graph whose nodes
>
> are values of some type and edges are directed paths with two paths (S
> and T) per each node?"
>
> No. A node is either a datum or a pivot. An edge is directed. S, T
> means the sources, targets of a node, if any. A node may have any
> number of M sources, any number N of targets, as long as M + N > 0.
So how would you represent , say, three entities like 'employee', 'department', 'company' ?
>
> For a connection from x to y we say x is a source of y, y is a target
> of x.
>
> S, T are also called A+, A- in the literature (A from "Adjacent").
>
>
Received on Thu Nov 10 2005 - 16:25:31 CST