设计关系数据库模式的优化综合算法

AN IMPROVED SYNTHESIS ALGORITHM OF DESIGNING RELATIONAL DATABASE SCHEME

An improved algorithm of designing relational database scheme is described in this paper. From a given set of FD's (Functional Dependencies) this algorithm can find a relational database scheme in EKNF(Elementary Key Normal Form)based on theory of subset closures, relational database and FD' s Hamiltonian cycles. This algorithm eliminates not only extraneous attributes and other redundancies, but also superfluities from a given set of functional dependencies. Following this algorithm, a better LR - minimum FD is obtained, and the time complexity of the algorithm is polynomial. So, this algorithm is more practical and efficient in designing a relational database scheme.