Processing group K closest pairs query in spatial databases

In this paper, a new form of distance-based query, group K closest pairs query, is proposed. This kind of query computes the aggregations of distances from objects of several data sets to objects of a central data set, and returns the K minimum group distances. In spatial databases, multiple-nearest-neighbor algorithm method and threshold algorithm are presented for the data sets stored in the R-tree family. A performance study based on extensive experiments shows that threshold algorithm outperforms multiple-nearest-neighbor algorithm.