A note on Schema Equivalence

In this paper we introduce some terminology for comparing the expressiveness of conceptual data modelling techniques, such as ER, NIAM, and PM, that are finitely bounded by their underlying domains. Next we consider schema equivalence and discuss the effects of the sizes of the underlying domains. This leads to the introduction of the concept of finite equivalence. We give some examples of finite equivalence and inequivalence in the context of PM.