XML-search Query Language: Needs and Requirements

This paper explores the needs of XML-search and makes comparisons between the INEX experience in evaluating XML retrieval and the recently proposed W3C requirements for extending XQuery and XPath to handle full-text retrieval. Our experience in INEX gave insight into some problems combining ranking with XML structured queries and more generally the needs from the users' perspective. INEX has focused on how to express the user needs through topics that may involve structural XML elements. How such user needs can be translated into XML queries has an impact on the requirements for an XML-search language. The analysis in this paper shows that the W3C requirements for extending XQuery and XPath with full-text search seem to address most of the needs identified through our first experiments with INEX. In particular, being able to specify an implementation dependent scoring function that allows ranking of answers. However, there are still issues concerning how the W3C requirements cater for combining structural requirements with ranking.