Some features of the TAXIS data model
John Mylopoulos, Harry K. T. Wong · Very Large Data Bases · 1980
This paper's principal goal is to provide a discussion on issues raised by the coexistence in a semantic data model of (i) An object-oriented framework including the notions of token, class and property as well as the IS-A and INSTANCE-OF relations; (ii) Transactions that can cause state changes; (iii) Special (null) values such as unknown, nothing and inconsistent. The paper presents a number of postulates that need to be satisfied by a database defined in forms of such features for its definition to be well-formed. The discussion uses as starting point TAXIS, a language for the design of interactive applications systems which offers all three types of features.