不确定数据查询处理

摘要

数据的不确定性在现实世界中的经济、军事、物流、金融、电信等领域普遍存在.不确定数据广泛应用于环境维护、市场分析、基于位置的服务LBS以及数量经济研究等应用.由于这些应用的重要性以及收集和累积的不确定数据数量的快速增长,查询这些数据已经成为一个重要的任务,并日益受到广大数据库研究者的关注.本文介绍了不确定数据查询的基本原理,并对不确定数据的近邻查询、逆向近邻查询、排序查询、Top-k查询以及连接查询进行了详细的讨论.同时对这些技术的优缺点进行了分析、对比.最后给出了未来的研究方向.%Data uncertainty is pervasive in various fields,for example,economy,military,logistic,finance and telecommunication,etc.Uncertain data are inherent in some important applications,such as environmental surveillance,market analysis,LocationBased Service(LBS),and quantitative economics research.Due to the inportance of those applications and the rapidly increasing amount of uncertain data collected and accumulated,querying large collections of uncertain data has become an important task and has received more and more attention from the database community in recent years.This paper introduces the principle of uncertain data query,and surveys the advance of the research on uncertain data query processing,including Nearest Neighbor(NN) query,Reverse Nearest Neighbor(RNN) query,Ranking query,top-k query and join query.By a detailed comparison,the pros and cons of the techniques are discussed.In the end,the problems in current research and some future research issues are outlined.