An Algorithm for Multi-way Distance Join Query

This paper presents K-DJQ algorithms for solving multi-way distance join query, which finds the K n-tuples from n spatial datasets that have the smallest distance value according to query graph. R-tree is used as index structure for each dataset. K-DJQ algorithm is recursive non-incremental approach following depth-first search strategy and synchronously traverses all R-trees, which returns the K n-tuples of the result all together at the end of the algorithm without producing any intermediate result. In addition, distance-based plane-sweep technique is used as optimization techniques for K-DJQ to reduce the total query processing time. Finally, performance and accuracy of K-DJQ algorithm are evaluated in terms of different K value and the number of datasets through experimentation.