The XPath language incorporates powerful primitives for formulating queries containing nested subexpressions which are existentially or universally quantified. However, even the b...
Previous works on automatic query clustering most generate a flat, un-nested partition of query terms. In this work, we are pursuing to organize query terms into a hierarchical s...
A RkNN query returns all objects whose nearest k neighbors contain the query object. In this paper, we consider RkNN query processing in the case where the distances between attri...
In this paper, we propose the Hybrid-Layer Index (simply, the HL-index) that is designed to answer top-k queries efficiently when the queries are expressed on any arbitrary subset ...