A Category Theoretic Method of Temporal Data Model

Temporal data model is the mainline of trends in temporal database technology, and it is the core and basis of temporal database system development. Existing temporal data models focus on specific implementation among different abstract levels, the lack of unified concepts and systematic formal descriptions, especially the deficiency of solid theoretical foundation for universality, flexibility and extensibility etc., leads to some difficulties to meet actual needs of the temporal database systems development. This paper presented FTDM (Formal Temporal Data Model) at higher abstract level in accordance with the status of quo of temporal data models, proposed the definition of data model reuse by the thinking of software reuse, and further made temporal data models family Mi based on FTDM. By the methods of category theory this paper also demonstrated some categorical properties of Mi, and analyzed the inherent relationship between temporal data models in Mi, which provided an efficient and convenient formalization theory framework for studying temporal data model, also provided solid theoretical foundations for development and design of temporal database system.