NORTII-HOU.AND Informatics and Computer Science A Model for Representing Topological Relationships between Complex Geometric Features in Spatial Databases ELISEO CLEMENTINI and PAOLINO DI FELICE Dipartimento di Ingegneria Elettrica, Universita di L 'Aquila, 67040 Poggio di Roio (AQ), Italy ABSTRACT Various models for the representation of topological relationships have been developed. The aim ofthis paper is to show that the set of relationships proposed in [7] (the CBM), for describing topological relationships among two-dimensional simple features, is applicable with few modifications to the case of complex features (that is, areas made up of several components possibly containing holes, lines with self-intersections, and/or more than two endpoints, and so on). The CBM offers a small set of topological relationships with high expressiveness which is proven to be mutually exclusive and complete, and therefore suitable to be embedded in a spatial query language. 1. INTRODUCTION Spatial database systems have constantly increased in popularity during the last few years. A kind of proof is the increasing success accredited by the database community to the series of conferences (Symposium on Large Spatial Databases) held bi-annually since 1989 [1, 2, 13, 16]. The major mo- tivation pushing research in spatial database systems is the large number of application domains they involve [18]. An incomplete list of these domains includes: geographic databases, scientific databases, pictorial databases, and CAD. Spatial data management imposes a number of new requirements on database systems if compared with traditional ones. Among the many, the formalization of spatial relationships among physical objects has a central role, because they occur in the majority of spatial queries. The following three examples are typical of spatial queries borrowed from the INFORMATION SCIENCES 90, 121-136 (1996) © Elsevier Science Inc., 1996 655 Avenue of the Americas, New York, NY 10010 0020-0255/96/$15.00 SSDI 0020-0255(95)00289-8