Minimization of PTQ under XSCs

XML is the standard for data representation and exchange over the Web. XSC is a concept of a pattern-based XML schema formalism. It models some structural constraints. Since the pattern tree is widely used in XML queries and the query efficiency depends on the size of the pattern, it is essential to minimize the size of the pattern tree. We consider the problem of minimization of pattern tree queries (PTQ) under some structural constraints for XML (XSCs). This is a new research field. This research can improve the query efficiency on some XML database with some structural constraints. In this paper, we study pattern tree minimization when taking XSCs into consideration. We develop a polynomial time algorithm called XSCM on this purpose. We complement our analytical results with an experimental study that shows the effectiveness of our pattern tree techniques.