基于语义相似度的数据库自适应查询松弛方法  

An Adaptive Query Relaxation Approach for Relational Databases Based on Semantic Similarity

作　　者：孟祥福[1] 严丽[2] 马宗民[1] 张富[1] 王星[1] 

机构地区：[1]东北大学信息科学与工程学院,沈阳110819 [2]东北大学软件学院,沈阳110819

出　　处：《计算机学报》2011年第5期812-824,共13页Chinese Journal of Computers

基　　金：国家自然科学基金(60873010;61073139);国家青年科学基金(61003162)资助~~

摘　　要：为了解决数据库空查询结果问题,提出了一种基于语义相似度的数据库自适应查询松弛方法.首先,基于初始查询条件和数据分布推测用户对查询指定属性的重视程度,据此提出了一种属性权重评估方法;然后,通过考察属性值的特征信息,分别提出了分类型属性值之间和数值型属性值之间的语义相似度评估方法;在此基础上,根据松弛阈值、属性权重和属性值之间的语义相似度,提出了一种自适应查询松弛重写算法.对于满足松弛查询的近似查询结果,按照它们对初始查询的满足度进行排序.实验结果表明,提出的属性权重和属性值之间的语义相似度评估方法性能稳定,评估结果合理,提出的查询松弛方法具有较高的查全率,能够较好地满足当前用户的需求和偏好.To deal with the problem of empty answers of the relational database,an adaptive query relaxation approach,which is based on semantic similarity,is proposed.Firstly,according to the query conditions and data distribution the importance of each specified attribute for the user is speculated,and then an attribute weight measuring method is proposed.Next,based on the properties of attribute values,the semantic similarity measuring method of categorical attribute value（resp.numerical attribute value） is proposed.According to the relaxation threshold,attribute weights and semantic similarities of attribute values,an adaptive query relaxation rewriting algorithm is proposed.The tuples satisfying the relaxed query are finally ranked according to their satisfaction degree.Results of experiments demonstrate that the performance and results of attribute weight and attribute values similarity measuring methods proposed are stable and reasonable respectively,the query relaxation method proposed has higher recall and can capture the user＇s needs and preferences effectively as well.

关 键 词：WEB数据库 查询松弛 属性权重 语义相似度 查询结果排序 

分 类 号：TP311[自动化与计算机技术—计算机软件与理论]