A Design of a Data Model Based on Abstraction of Symbols
Takayuki Dan Kimura · The Computer Journal · 1985
Abstract Databse System (ADS) is introduced as a data model in which the notions of symbol and abstraction play a fundemental role in the formal description and structuring of databases. The mechanism of abstraction in ADS is based on the abstraction operator of the lambda calculus. Important concepts in data modeling, such as entity set, entity type, property, attribute, relations, association, constraint, type checking and cardinality, are formally representable in the framework of abstractions on symbols. Thus, the number of primitive concepts in ADS is relatively small. ADS is part of an effort to develop a design methodology for an enduring medical information system, an area where frequent changes in the conceptual schema are anticipated and multi-level abstraction is advantageous.