面向对象数据库中的数据依赖和规范化

Data Dependency and Normalization in OODB

从分析面向对象数据库中的数据依赖着手，提出对象函数依赖的概念，它反映了面向对象数据库中对象标识符、复杂对象及集合类型的特点．在对象函数依赖基础上，提出以分解为基础的类模式规范化方法，并且特别引入语义相关集的概念，以解决类模式分解后方法的处理，最后，给出类模式分解的形式化定义并证明了类模式的任一分解都是无损分解．

Beginning with the analysis of data dependencies on object oriented databases, this paper first presents the concepts of object functional dependencies, which reflect the distinct characteristics of an object oriented data model such as object identifiers, complex attributes and collection data types. The steps of normalization based on the decomposition for a class schema are illustrated, and the concept of semantically related set is also proposed to deploy the methods. Furthermore, the definition of the decomposition for a class schema is given and the assertion that the decomposition for a class schema is always non lost is proved.