Cardinality consistency of derived objects in DOOD systems

Deductive object oriented database languages are faced with the problem of dealing with the new concepts of the object oriented approach: object identity, inheritance, method, and complex object structure. Complex object structures raise a consistency problem for derived objects. To the best of our knowledge, no method has been proposed to do a static check of the consistency of deductive programs dealing with complex objects. In this paper we propose a solution based on a deductive language, called ERCLog, for an object and relationship data model. ERCLog explicitly manages the cardinalities of the attributes of the objects and of the links between objects. This information allows the static checking of the consistency of the programs.