A C++ Binding for Penguin: a System for Data Sharing among Heterogeneous Object Models

The relational model supports the view concept, but relational views are limited in structure. OODBMSs do not support the view concept, so that all applications must share the same arrangement of object classes and inheritance. We describe the Penguin system and its support for the view concept. Each application can have its own arrangement of object classes and inheritance, and these are de ned as views of an integrated, normalized conceptual data model, in our case the Structural Model. We de ne view-objects in a language-independent manner on top of the conceptual data model. These view-objects can be complex objects supporting a composite structure. We discuss the extension of Penguin to support PART-OF (reference) and IS-A graphs for composite view-objects. We also discuss the C++ binding to Penguin, where C++ code is generated for object classes corresponding to the view-objects along with basic operations on them (creation, query, navigate, browsing, and update).