XQuery is a post-relational database language for XML that is now being developed by the World Wide Web Consortium, W3C.  click here to try it

Language Features

Supports queries against semistructured XML data. Automatic type checking frees the user from having to declare too many types. Data types can be defined using regular expressions. Data types are used to validate XML content. Generalized path expressions are used to access data in XML trees. Eliminates the need for relational normalization when used with read-only data. This language coupled with XML-based data storage may someday gain significant market share alongside SQL, the prevailing database standard.

XQuantum Database

XQuantum™ is our implementation of a subset of the XQuery Language standard, along with its type inference system.  The system brings advanced search capabilities to Internet portals and provides unparallelled levels of data integration with rich content.  learn more