In this paper we study the problem of deciding whether a regular path query over views in data-integration systems can be re-expressed without recursion. The problem becomes chall...
We consider the problem of finding and ranking paths in semistructured data without necessarily knowing its full structure. The query language we adopt comprises conjunctions of r...
Carlos A. Hurtado, Alexandra Poulovassilis, Peter ...
In this paper we study the following problem. Given a database and a set of queries, we want to find, in advance, a set of views that can compute the answers to the queries, such ...
In previous papers we have proposed a graphical query language for expressing traversal recursions in labelled, directed graphs. A fundamental feature of the language is the use o...
XPath is the standard language for addressing parts of an XML document. We present a sound and complete decision procedure for containment of XPath queries. The considered XPath f...