A Novel Two-Phase XML Keyword Query Algorithm

Many existing XML keyword query approaches adopt the subtrees rooted at the smallest lowest common ancestor of the keyword matching nodes as the basic result units. The structural relationships among XML nodes are excessively emphasized in these approaches but the context meanings of XML nodes are not taken seriously. To change this situation and improve the matching between users' query intentions and final query results, we propose a two-phase XML keyword query algorithm. In the first phase of the algorithm, users can select the suitable context meanings of keyword matching nodes to match their query intentions, and the eligible keyword matching nodes will be found in the second phase to return more accurate query results efficiently. The effectiveness and the efficiency of the algorithm are demonstrated through extensive experiments.