On supporting structure-agnostic queries for XML

Abstract

XML has rapidly emerged as the standard for the interchange of data in numerous application areas. Many software vendors now offer XML servers to store and retrieve XML documents. To allow for content-based queries, query languages have also been designed. The query languages require the users to know the structure of the XML documents and specify search conditions on the structure. This navigational access to XML documents is a natural consequence of the hierarchical structure of XML. However, it is also desirable to allow the users to formulate structure-agnostic queries against XML documents, to complement the current navigation-based queries. We have developed a query processor to evaluate structure-agnostic XML queries. In this article, we motivate the need for structure-agnostic, that is, non-navigational, queries against XML, and offer it as a worthy subject of further research and development.