摘要
本文给出一种层次关系数据库设计法.它考虑了包含语义及结构信息的自然层次联系,提出层次依赖与关系层次树的概念,引入关系的分层结构思想来构造数据库视图.文中给出了完整的设计过程与详细的算法,以表示层次、群体与凝聚联系的最小基本依赖集为基础,对初始关系模式逐步求精分解而建立关系层次树,最后转换成层次关系数据库模式.
This paper presents an approach to the design of a hierarchical relational database. The natural hierarchical relationship which covers information in semantics and structure has been considered. The new concepts of hierarchical dependency and hierarchical tree of relations are proposed. By the relation hierarchies idea, database views are constructed. A total design procedure with detailed algorithms is described. The hierarchical trees of relations are built by decomposing refinedly the initial relation schemes on the basis of the minimal set of elementary dependencies representing the relationships of hierarchies, clusters and aggregations, and then they are converted into a hierarchical relational database schema.
出处
《华中理工大学学报》
CSCD
北大核心
1990年第1期55-61,共7页
Journal of Huazhong University of Science and Technology
关键词
关系数据库
关系模式
数据库设计
Data relationship
Database design
Relational database
Functional dependency
Multivalued dependency
Relation scheme
Directed tree
