IMCS/Publications/BASM/Issues/BASM n.2 (15), 1994/

β-acyclic schemes of databases. (Romanian)

Authors: Cotelea V., Ceban Ia.


Four types of cycle on hypergraph are examined: $\beta$-cycle, week $\beta$-cycle, Graham cycle, independent cycle. It is shown that between these types of cycle exists the following relations: $\beta$-cycle $\Rightarrow$ week $\beta$-cycle $\Rightarrow$ Graham cycle $\Rightarrow$ independent cycle. Several necessary and sufficient conditions for database schemes to be $\beta$-acyclic are exposed.

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