Date: Wed 03 Jul
Time: 16.00
Place: Sala Conferenze

Speaker: Hanan Samet (Univ. of Maryland)
Title: Ranking in Graphical Databases (joint work with Gisli R. Hjaltason)
Reference: Leila de Floriani

Abstract. An algorithm for ranking spatial objects according to increasing distance from a query object is introduced and analyzed. The algorithm makes use of a hierarchical spatial data structure. The intended application area is a database environment, where the spatial data structure serves as an index. The algorithm is incremental in the sense that objects are reported one by one, so that a query processor can use the algorithm in a pipelined fashion for complex queries involving proximity. It is well suited for $k$ nearest neighbor queries, and has the property that $k$ needs not be fixed in advance. The algorithm has been used as the basis of a browser for graphical objects in a relational database.