Object database systems: Functional architecture

Abstract

Object database systems have now been on the market for about 4 years. They have evolved considerably and are now slowly converging to common and accepted overall architecture. The goal of this paper is to describe this architecture. An object database system supports an object database model. This model can be decomposed into four different aspects: data, behavior, persistence and naming. An object database system consists of a database engine supporting all or part of the database model. On top of this engine are implemented a number of language interfaces: an object definition language, an object query language and one or several programming languages. These programming languages can be internal or external. Internal languages are fully managed within the system, and are in general proprietary extensions of existing programming languages (C, Smalltalk, Lisp or C++). External languages are managed outside of the database system and are in most case standard languages (C++ or SmallTalk).