Distributed approach of continuous queries with KNN join processing in spatial data warehouse

The paper describes realization of distributed approach to continuous queries with ANN join processing in a spatial telemetric data warehouse. Due to dispersion of the developed system, new structural members were distinguished - the mobile object simulator, the ANN join processing service and the query manager. Distributed tasks communicate using JAVA RMI. The ANN queries (k Nearest Neighbour) joins every point from one dataset with its k nearest neighbours in the other dataset. In our approach we use the Gorder method, which is a block nested loop join algorithm that exploits sorting, join scheduling and distance computation filtering to reduce CPU and I/O usage.