Study On α-acycle In Temporal Database

In the operation of temporal database, we usually hope that it has some excellent property, such as convenient database maintenance, less time and space cost, higher time and space working efficiency, and the settlement of problems which exists in the query etc.α-acycle database is the database that has plenty of wonderful property. It introduces the definition of hypergragh, use the hypergraph to express the database module, hence many property of the database module can be depicted by the corresponding hypergraph conveniently.This paper introduces the definition ofα-acycle temporal hypergraph, concise temporal hypergraph, the projection of temporal hypergraph and so on in the temporal module, we use TGraham algorithm to judge if there is cycle problem in the temporal hypergraph, and give some property ofα-acycle temporal module, e.g., the integrity coincidence and both coincidence are equivalence in theα-acycle temporal database, it also has bald joint expression and entire reduction and so forth.Commonly, semantic ambiguity is from some attribute that represents the different function of the same thing, or represents two attributes of the same data domain. In the query it is efficient to delete each cycle in the hypergraph to over the semantic ambiguity. The study of hypergraph andα-acycle in the temporal database has important meaning to perfect and develop the temporal database and the validity and speediness of query, meanwhile, it also enforce the function of temporal database better.The paper studies theα-acycle in the domain of temporal database, it overcomes the semantic ambiguity in the temporal query, this part is blank in the field of temporal database. The write will work hard on the study and perfection ofα-acycle.