【作者】 侯士江； 刘国华； 余靖； 褚兵义；

【机构】 燕山大学信息科学与工程学院；

【摘要】 <正>1 引言传统空间数据库中的kNN查询问题已经得到深入研究。这种形式的查询经常用于地理信息系统 (Geographical Information Systems,GIS),并且定义为:给定一组空间对象和一个查询点,查询距离查更多还原

【Abstract】 In spatial network databases(SNDB) .objects are restricted to move on pre-defined paths(e. g. ,roads)that are specified by network. The network distance between objects(e. g. ,a vehicle and the restaurants)depends on the connectivity of the network rather than the objects’coordinates. One of the most importantkinds of queries in SNDB is k nearest neighbors(kNN) query. Network distance isused in such a query instead of the Euclidean distance. Index structures that are designed for traditional spaces where the distance between objects is only a function of their spatial attributes, can’t properly approximate the distances in SNDB and hence, the solutions can’t be extended to SNDE In this paper,a storage schema with a set of index structures is first proposed, and then a kNN-query algorithm for SNDB is proposed and its validity is analyzed.更多还原