Declarative reconstruction of an object oriented data model with roles

This paper is aimed at showing how a simple non-deterministic extension of Datalog IS sufficient to declaratively reconstruct the essence of object-oriented data models witl1 roles. The target language is a subset of the logical (late language LDL++ [AOTZ93], The reconstruction is performed by means of compilation into the extended Datalog language of the basic features of the object model, including the schema definition language the query language and the basic update operations. The purpose of this compilation is twofold. On one side, it provides a logical semantics of the object mode], as the semantics of the target language is assigned in purely logical terms [SZ90 ZAO93]. On the other side, the proposed compilation forms the basis of a realistic implementation, as LDL++ is efficently executed by meabs of fixpoint procedure with "in situ" updates