XML : How to specify in an XML schema that either one of two fields must be present?ie how to make choice [duplicate]

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• How to make either of the fields mandatory in XML schema 2 answers

I have a requirement like either ParcelNumber or co-ordinates like CoordinateX or CoordinateY mandatory and these two contains different hierarchy in XML . So if the input xml contains parcel number it should return success or if it contains co-ordinates, then it should return success.I created following schema ,and it will return success if i send only parcel number, but if i send Co-ordinates it will fail ,it is asking to send parcel number which is wrong.How to achieve it.In Nutshell i have following question

  1>If i send both coordinates  and no parcel number it should return success  2>IF i send x coordinate then it should fail and ask to send Y co ordinate    

Following is what i have done so far

  <?xml version="1.0" encoding="utf-8"?>  <xsd:schema      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"      xmlns:xsd="http://www.w3.org/2001/XMLSchema"              attributeFormDefault="unqualified" elementFormDefault="qualified">      <xsd:element name="NOCPlantMapRequest">          <xsd:complexType>              <xsd:sequence>                  <xsd:element name="Applicationtype" minOccurs="0" type="xsd:string"/>                  <xsd:element name="RelatedNOCRefNumber" minOccurs="0" type="xsd:string"/>                  <xsd:element name="WorkLocation" minOccurs="1" maxOccurs="1" type="LocationType"></xsd:element>              </xsd:sequence>          </xsd:complexType>      </xsd:element>      <xsd:complexType name="LocationType">          <xsd:all>              <xsd:element name="ParcelNumber" type="ParcelNumberType" maxOccurs="1"/>              <xsd:element name="WorkArea" type="WorkAreaType" maxOccurs="1"/>              <xsd:element name="Roads" type="RoadListType" maxOccurs="1"/>          </xsd:all>      </xsd:complexType>      <xsd:complexType name="RoadListType">          <xsd:sequence>              <xsd:element name="WorkLocationRoad" type="WorkLocationRoadType" minOccurs="0" maxOccurs="unbounded"/>          </xsd:sequence>      </xsd:complexType>      <xsd:complexType name="WorkLocationRoadType">          <xsd:sequence>              <xsd:element name="RoadName" type="xsd:string"/>          </xsd:sequence>      </xsd:complexType>      <xsd:complexType name="CommunitiesListType">          <xsd:sequence>              <xsd:element name="WorkLocationRoad" type="WorkLocationRoadType" minOccurs="0" maxOccurs="unbounded"/>          </xsd:sequence>      </xsd:complexType>      <xsd:simpleType name="ParcelNumberType">          <xsd:restriction base="xsd:string"/>      </xsd:simpleType>      <xsd:complexType name="WorkAreaType">          <xsd:sequence>              <xsd:element name="WorkArea" minOccurs="0" maxOccurs="unbounded">                  <xsd:complexType>                      <xsd:sequence>                          <xsd:element name="Coordinates" minOccurs="1" type="CoordinatesType"/>                          <xsd:element name="Communities" type="CommunitiesListType" maxOccurs="1"/>                      </xsd:sequence>                  </xsd:complexType>              </xsd:element>          </xsd:sequence>      </xsd:complexType>      <xsd:complexType name="CoordinatesType">          <xsd:sequence>              <xsd:element name="WorkLocationCoordinate" type="WorkLocationCoordinateType"/>          </xsd:sequence>      </xsd:complexType>      <xsd:complexType name="WorkLocationCoordinateType">          <xsd:sequence>              <xsd:element name="CoordinateX" type="xsd:string"/>              <xsd:element name="CoordinateY" type="xsd:string"/>          </xsd:sequence>      </xsd:complexType>  </xsd:schema>    

EDIT Any idea of how to use choice properly here

EDIT i did like but no luck at all

  <xs:complexType name="tSome">  <xs:sequence>    <xs:choice>      <xs:element name="ParcelNumber" type="ParcelNumberType" />      <xs:element name="WorkArea" type="WorkAreaType" />    </xs:choice>    <xs:element name="Roads" type="RoadListType" />  </xs:sequence>  </xs:complexType>