XML Shema & Unique Particle Attribution

Question

Hi all,
I am trying to create an xml schema but I face the following error:
cos-nonambig: "":content and "":content (or elements from their substitution group) violate "Unique Particle Attribution". During validation against this schema, ambiguity would be created for those two particles. [65]
the above error is caused by the following section of the xsd file (specifically in the xs:choice of the question element definition):
    <xs:element name="content" type="xs:anyType"/>
    <xs:element name="weight" type="xs:positiveInteger"/>
    <xs:group name="simpleQuestionItems">
        <xs:sequence>
            <xs:element ref="content"/>
            <xs:element ref="weight"/>
        </xs:sequence>
    </xs:group>
    <xs:group name="complexQuestionItems">
        <xs:sequence>
            <xs:element ref="content" minOccurs="0" maxOccurs="1"/>
            <xs:element ref="weight" minOccurs="0" maxOccurs="1"/>
            <xs:element ref="question" minOccurs="1" maxOccurs="unbounded"/>
        </xs:sequence>
    </xs:group>
    <xs:element name="question">
        <xs:complexType>
            <xs:choice>
                <xs:group ref="simpleQuestionItems"/>
                <xs:group ref="complexQuestionItems"/>
            </xs:choice>
        </xs:complexType>
    </xs:element>Do you know how can I avoid this problem while writing something similar?

Answer 1

Hello,
See i have made some changes accordingly but still there may be some problems. I dont know why you want your schema structure in circular one. (i.e. from question group you want to ref complex and again from it you are ref to question so it is giving name collision problem)
One another think do follow to mention the namespace (target and for your xsd) whenever you do your new xsd. Generally all project xsd's belong to only one namespace( but still as per your convience you can mention multiple)
<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:ab="http://www.yourcompany.com/XMLSchema/ProjectName" xmlns:xs="http://www.w3.org/2001/XMLSchema" targetNamespace="http://www.yourcompany.com/XMLSchema/ProjectName" elementFormDefault="qualified" attributeFormDefault="unqualified">
     <!--<xs:element name="content" type="xs:anyType"/>
     <xs:element name="weight" type="xs:positiveInteger"/>-->
     <xs:group name="simpleQuestionItems">
          <xs:sequence>
               <xs:element name="content" type="xs:anyType"/>
               <xs:element name="weight" type="xs:positiveInteger"/>
               <!--<xs:element ref="ab:content"/>
               <xs:element ref="ab:weight"/>-->
          </xs:sequence>
     </xs:group>
     <xs:group name="complexQuestionItems">
          <xs:sequence>
               <!--<xs:element ref="ab:content" minOccurs="0"/>
               <xs:element ref="ab:weight" minOccurs="0"/>-->
               <xs:group ref="ab:simpleQuestionItems" minOccurs="0"/>
               <xs:element ref="ab:question" maxOccurs="unbounded"/>
          </xs:sequence>
     </xs:group>
     <xs:element name="question">
          <xs:complexType>
               <xs:choice>
                    <xs:group ref="ab:simpleQuestionItems"/>
                    <xs:group ref="ab:complexQuestionItems"/>
               </xs:choice>
          </xs:complexType>
     </xs:element>
</xs:schema>
Regards,
Sachin Kulkarni, Pune- India