One space contains a set of 2-dimensional points. This set of points is large and dynamic, so the data set is stored in a B-tree on disk. The query region is a single, box-shaped object. Because this data set contains a small amount of static data, (just one box), it makes sense to use a sorted array as the underlying data structure. Geophile combines these two spaces using spatial join to find the points inside the query region. Geophile can also be used to cluster the points on disk, to minimize the number of disk accesses required by the search. |