A Faceted-Navigation System for QCDml Ensemble XML Data

In this paper we describe a faceted navigation system for QCDml ensemble XML data, which is an XML-based metadata format for ILDG (International Lattice Data Grid). A faceted navigation system allows a user to search for one's desired information in an exploratory way, thereby enabling the user to browse a set of XML data without using specialized query languages such as XPath and XQuery. However, designing a faceted navigation interface for XML data is not straightforward due to the tree and flexible, tree-like nature of XML. In this work, we attempt to design and implement a dedicated faceted navigation system for QCDml on top of an XML database. The interface is designed by taking the domain experts' usability into account. We also care about the system's performance. In general, the process of faceted navigation is computationally expensive because of the need for aggregate computation of each available facets. In order to alleviate this, we make use of a relational database system as the engine to speed up the aggregate computation. We finally demonstrate the implemented faceted navigation system, which has been made available on the Web.