XML 'Plain' XML Format

The "Plain" XML contain elements to hold the extra fields (highlighted in bold).

<?xml version="1.0" encoding="utf-8"?>
<xs:schema attributeFormDefault="unqualified" elementFormDefault="qualified" 
           targetNamespace=" http://xmlns.oracle.com/LandisGyrUsage" 
           xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xs:element name="MeterReads">
    <xs:complexType>
      <xs:sequence>
        <xs:element name="MeterRead">
          <xs:complexType>
            <xs:sequence>
              <xs:element name="Origin"/>
              <xs:element name="ServProvExtRefId"/>
              <xs:element name="RecordType">
                  <xs:simpleType>
                    <xs:restriction base="xs:string">
                      <xs:enumeration value="MEPMD01" />
                      <xs:enumeration value="EMED01" />
                    </xs:restriction>
                  </xs:simpleType>
                </xs:element>
              <xs:element name="RecordVersion" minOccurs="0">
                  <xs:simpleType>
                    <xs:restriction base="xs:string">
                      <xs:enumeration value="20080519" />
                    </xs:restriction>
                  </xs:simpleType>
                </xs:element>
              <xs:element name="TimeStamp" />
              <xs:element name="Premise" minOccurs="0" />
              <xs:element name="ESIID" minOccurs="0" />
              <xs:element name="Provisioned" minOccurs="0" />
              <xs:element name="MeterID" />
              <xs:element name="Purpose" minOccurs="0" />
              <xs:element name="Comodity" minOccurs="0" />
              <xs:element name="Units" minOccurs="0" />
              <xs:element name="CalcConst" minOccurs="0"/>
              <xs:element name="Interval" minOccurs="0"/>
              <xs:element name="Count" minOccurs="0"/>
              <xs:element name="FirstIntervalDateTime" />
              <xs:element name="Data">
                <xs:complexType>
                  <xs:sequence>
                    <xs:element name="Row" maxOccurs="unbounded" minOccurs="0">
                      <xs:complexType>
                        <xs:attribute name="v" />
                        <xs:attribute name="s" />
                      </xs:complexType>
                    </xs:element>
                  </xs:sequence>
                </xs:complexType>
              </xs:element>
              <xs:element name="kWh" minOccurs="0" />
              <xs:element name="Peak" minOccurs="0" />
              <xs:element name="PeakDateTime" minOccurs="0" />
              <xs:element name="Dmd" minOccurs="0" />
              <xs:element name="TouA" minOccurs="0" />
              <xs:element name="TouB" minOccurs="0" />
              <xs:element name="TouD" minOccurs="0" />
              <xs:element name="TouC" minOccurs="0" />
              <xs:element name="TouE" minOccurs="0" />
              <xs:element name="Volts" minOccurs="0" />
              <xs:element name="PF" minOccurs="0" />
              <xs:element name="ExtraFields" minOccurs="0">
                <xs:complexType>
                  <xs:sequence>
                    <xs:element name="ExtraField" maxOccurs="255" minOccurs="0">
                      <xs:complexType>
                        <xs:sequence>
                          <xs:element name="FieldName" minOccurs="0"/>
                          <xs:element name="FieldValue" minOccurs="0"/>
                        </xs:sequence>
                      </xs:complexType>
                    </xs:element>
                  </xs:sequence>
                </xs:complexType>
              </xs:element>
              <xs:element name="RawData"/>
            </xs:sequence>
          </xs:complexType>
        </xs:element>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
</xs:schema>