Institut fur Informatik, Albert-Ludwigs-Universitat D-79110 Freiburg, Germany e-mail:

Florid is a deductive object--oriented database system relying on F-logic, which as a distinctive feature provides rich modeling facilities. In this paper we first give an overview about the language and its implementation. Furthermore, some examples illustrate advanced data modelling, particularly the solution of some nonmonotonic problems using inheritance is pointed out. 1 Introduction Florid -- F-Logic Reasoning In Databases, provides an implementation of all essential features of F-logic [8], which is a powerful language combining the advantages of deductive databases with the rich modeling capabilities of object oriented concepts (objects, methods, class hierarchies, nonmonotonic inheritance). The language is one of the most advanced in the deductive object oriented database (DOOD) area, providing a uniform handling of data and schema (class hierarchy etc.) which allows among others data--dependent schema definition by rules. Recently, several other prototypes for DOOD have been..