Model Transformations in Designing the ASSO Methodology

ASSO, an innovative conceptual methodology which combines features of database design with the formal method B, has been defined in order to ensure the flexibility of semantic data models, the efficiency of object models and design correctness. Starting from a directed acyclic graph of classes supported by semantic data models, a formal mapping generates classes supported by object models. The classes supported by semantic data models are then extended with aspects of behavioural modelling: a relationship with the B model is established and the consistency proofs of the whole schema are reduced to small obligations of B. This chapter evidences how ASSO is based on model transformations. These have been introduced with various purposes: to map semantic data models to object models, to integrate static and dynamic modelling, to link formal and informal notations and to relate the conceptual schema and the logical schema of the methodology.