Per Bothner

The World Wide Web Consortium is working on finalizing the specification for XQuery, aiming for a final release in mid to late 2002. XQuery is a powerful and convenient language that's designed for processing XML data - not just files in XML format, but other data (including databases) whose structure (nested named trees with attributes) is similar to XML. XQuery is an interesting language with some unusual ideas. This article is intended to give you a hawk's-eye view of XQuery, introducing the main ideas you should understand before you go deeper...or actually try to use it! An Expression Language The first thing to notice is that in XQuery everything is an expression that evaluates to a value. An XQuery program or script is just an expression, together with (optionally) some function and other definitions. So the following: 3+4 is a complete and valid XQuery progr... (more)