一种基于XML小枝查询片段松弛的近似查询与结果排序方法  

Approximate Query and Results Ranking Approach Based on XML Twig Query Fragment Relaxation

作　　者：魏珂[1] 任建华[1] 孟祥福[1] 

机构地区：[1]辽宁工程技术大学电子与信息工程学院

出　　处：《计算机科学》2012年第10期164-169,共6页Computer Science

基　　金：国家青年科学基金项目(61003162)资助

摘　　要：提出了一种基于XML小枝查询片段松弛的近似查询与结果排序方法来实现用户在XML文档中的近似查询:通过收集用户的查询历史来推测用户偏好,并以此计算原始小枝查询分解得到的查询片段的重要程度,然后按照重要程度的排序进行查询松弛;在松弛方法中,根据查询片段数目的不同采用不同的松弛方法,若片段数目较多则以查询片段为粒度对其松弛,较少则以查询结点为粒度对数值查询与非数值查询采用不同的方法进行松弛,得到最为相关的近似查询结果;最后按近似查询结果对原始查询和用户偏好的满足程度进行排序并输出。实验证明,该近似查询方法能够较好地满足用户的需求和偏好,具有较高的查全率和准确率。Based on XML twig query fragments relaxation,this paper proposed an approximate querying and results ranking approach to achieve the approximate query results against XML documents：our method gathers the query history to speculate the user＇s preferences,which is used to calculate the importance for each query fragment of the twig query,and relax the original query according to the sequence of the fragments＇ importance;based on the number of query fragments we adopt different relax way：if the number2,relax the original query according to the granularity of the fragment;if the number2,relax the original query according to the granularity of query node,and adopt a different way to relax the numerical query and non-numerical query,and then obtain the most relevant query results.Finally,the relevant query results are ranked based on their satisfaction degree to the original query and the user preferences.Our experiment shows that the approximate querying and the results ranking approach can efficiently meet the user＇s needs and user＇s preferences,has the high recall and precision.

关 键 词：小枝查询 近似查询 查询松弛 用户偏好 结果排序 

分 类 号：TP311.131[自动化与计算机技术—计算机软件与理论]