The XML Twig Approximate Query Approach Based on Query Fragment Relaxation
To deal with the problem of approximate query against XML documents,based on the query fragment relaxation,this paper proposes a XML twig approximate querying approach.The approach leverages the query history to speculate the user preferences,which is used to assign the importance for each query fragment of the given twig query.Then,the query fragment importance is used to relax the original twig query.The first query fragment to be relaxed must be the least important query fragment and thus the most relevant query results can be obtained.Finally,the relevant query results are ranked according to their satisfaction degree to the original query and the user preferences.The experimental results demonstrate that the query relaxation and results ranking approach presented in this paper has the high recall and precision,and can efficiently meet the user′s needs and preferences as well.