ADO.Net XML Provider

The WilsonXmlDbClient is an ADO.NET provider that enables Xml to be worked with just like any other database in .NET. It supports the most common Select, Insert, Update, and Delete SQL syntax, as well as tranactions and parameters.

Wilson.XmlDbClient is the original open source release by Paul Wilson. It includes:

XmlDbCommand
XmlDbDataReader
XmlDbDataAdapter
XmlDbConnection
XmlDbParameter
XmlDbTransaction
XmlDbException

http://code.msdn.microsoft.com/WilsonXmlDbClient