An application of the theory of graphs and hypergraphs to the decomposition of relational database schemes
An application of the theory of graphs and hypergraphs to the decomposition of Relational Database Schemas is studied.
Four new characterizations of cyclic hypergraphs are given.
Cyclic pairs of nodes are defined and it is proved that their presence characterizes cyclic hypergraphs. An algorithm to detect cyclic pairs is given.
Finally this concept is generalized to cyclic nodes and cyclic sets and it is proved that a hypergraph can be decomposed in a cyclic part and an acyclic part. In this way the acyclic part of a cyclic hypergraph can be isolated.
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