XQueryViz: A Visual Dataflow XQuery Tool

In this paper we introduce a dataflow-like visual syntax for writing XQueries. We also describe the functionalities, capabilities and pitfalls of the environment/prototype that supports the construction of visual XQueries. Our prototype allows users to visualize an XML schema, and makes use of its visual representation, using direct manipulation, to build the XPath of an XQuery. It also supports a round trip conversion; that is it converts a textual XQuery to a visual one and vice versa. To evaluate the usability of our visual syntax and the prototype in which the visual XQuery can be built, we have designed a case study to detect the strength and weaknesses of our approach. The results of the subjects we studied show that our approach of writing visual XQueries, using a visual dataflow-like syntax suffers from the lack of strict dataflow syntax and semantics. In future work we intend to address this issue and further improve on what we now have.