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From: "Neo" <neo55592@hotmail.com>
Newsgroups: comp.databases.theory
Subject: Re: Generalised approach to storing address details
Date: 13 Dec 2006 21:12:28 -0800
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> The relational algebra lacks the computational power needed to compute the transitive closure.

Below dbd does transitive closure over the following hierarchy:

god
  adam
     john
     mary
  eve
     john
     mary

(new 'god)
(new 'adam)
(new 'eve)
(new 'john)
(new 'mary)

(set god child adam)
(set god child eve)
(set adam child john)
(set adam child mary)
(set eve child john)
(set eve child mary)

(; Get god's children)
(; Gets adam, eve, john and mary)
(getRelD god child *)