Essential XQuery - The XML Query Language

XQuery or XML Query Language is a W3C specification (http://www.w3.org/TR/xquery) designed to provide a flexible and standardized way of searching through (semi-structured) data that is either physically stored as XML or virtualized as XML (such as XML Views over relational data). To give you an analogy, SQL is used to query relational data, XQuery is a standard language for querying XML data. In addition, XQuery also allows general processing of XML (such as creating nodes). Currently in the last call working draft status, the W3C XQuery specification will hopefully get the recommendation status this year. This article is an introduction to XQuery language. It is based on November 2003 working draft. (Click here to see the changes made to 23rd July 2004 XQuery 1.0 Working Draft.)

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