public void InsertXml(TdCommand cmd)
{
    // The first parameter will be a TextReader.
    // StreamReader inherits from TextReader.
    StreamReader xmlStream = new StreamReader(@"c:\XmlFile1.xml");

    // The second parameter will be a XmlReader.
    // XmlTextReader inherits from XmlReader.
    XmlTextReader xmlData = new XmlTextReader(@"c:\XmlFile2.xml");
    cmd.Parameters.Clear();

    cmd.CommandText = "insert into XmlTable (XmlColumn1, XmlColumn2) values (?, ?)";
   
    cmd.Parameters.Add(null, TdType.TdXml);
    cmd.Parameters[0].Value = xmlStream;
   
    // if the Offset and Size properties are used, it is the responsibility of the
    // application to make sure that the resulting Xml that is sent to the Advanced SQL Engine
    // is valid. An exception will be thrown if the Xml is invalid.
    cmd.Parameters[0].Size = 100;
    cmd.parameters[0].Offset = 50;

    cmd.Parameters.Add(null, TdType.TdXml);
    cmd.Parameters[1].Value = xmlData
   
    // The Size and Offset properties are ignored when a XmlReader is used.

    // Sending data to Teradata
    TdDataReader reader = cmd.ExecuteNonQuery();
}