These proceedings contain the technical papers selected for presentation at the Fourth International Symposium on Large Spatial Databases (SSD '95) held in Portland, Maine, August 6-9, 1995. With the conferences in Santa Barbara (1989), Zurich (1991), and Singapore (1993), the International Symposium on Large Spatial Databases has become the premier meeting for researchers, developers, and practitioners focusing on the integration between database management systems and geographic information systems. SSD '95 brought together computer scientists and GIS experts to explore advances in modeling, storage, and retrieval of massive spatial data sets, and to discuss the requirements from new, demanding application domains.
From among sixty submissions of full papers by authors from sixteen countries, the program committee selected twenty-three outstanding papers for inclusion in this volume. The acceptance rate at SSD continues to be highly competitive, which we believe is a sign of an active research community.
The papers included in this volume show that we are on the verge of a new generation of spatial database management systems motivated by the needs of digital spatial libraries, interoperable systems and Open GIS, and the World-Wide Web. Discussions have moved away from the design of new spatial access methods, more SQL extensions, or yet another object-oriented spatial data model. This is not to say that the problems of spatial query languages and conceptual modeling for spatial data have been solved, but rather the attention for innovative advancements has shifted. New, exciting topics have come up, such as data mining in large spatial databases. Other areas have been established as topics with great potential for advanced use such as spatial joins and spatial reasoning for intelligent access to spatial data.
The conference included two tutorials on spatial databases (by Hanan Samet) and spatio-temporal information systems (by Mike Worboys). Also two panels on Open GIS and New Applications of Spatial Databases were included to stimulate discussion of emerging issues. For the first time at SSD, we offered a software demonstration session. We are in debt to the many people who made this event happen. The program committee and the external referees provided invaluable assistance with their reviews. Hanan Samet deserves special thanks for hosting the program committee meeting at the University of Maryland. The conference would have been impossible without the local organization of Kathleen Hornsby. We also very much appreciated the assistance of Eileen Herring and Blane Shaw.
We are very grateful for the support given by our corporate sponsors: Environmental Systems Research Institute, Inc., Lockheed Martin, Management & Data Systems, and Oracle Corporation. Cooperation with ACM SIGMOD and the National Center for Geographic Information and Analysis is also gratefully acknowledged.