Major milestone. XQuery is going to be fundamentally important.
Based on widespread implementation experience and extensive feedback from users and vendors, W3C has published eight new standards in the XML Family to support the ability to query, transform, and access XML data and documents. The primary specifications are XQuery 1.0: An XML Query Language, XSL Transformations (XSLT) 2.0, and XML Path Language (XPath) 2.0; see the full list below.
XML Query (XQuery) describes a database query language for XML data.
"XQuery will serve as a unifying interface for access to XML data, much as SQL has done for relational data," said Don Chamberlin of IBM Almaden Research Center, co-inventor of the original SQL Query language and one of the co-editors of XQuery 1.0. "Since virtually any kind of information can be represented using XML, I expect XQuery to play a central role in unifying information from many different sources. Companies across a wide range of industries can use XQuery to pull together structured and semi-structured information for processing in a unified way."