I am trying to build a C# class from a XSD file. In short I'm getting a circular reference error when trying to execute the XSD.exe tool:
Group 'setFilterCondition' from targetNamespace='http://developer.cognos.com /schemas/report/7.0/' has invalid definition: Circular group reference.
I pulled the definition of the group and I have the following XSD for it:
<xs:group name="setFilterCondition">
<xs:annotation>
<xs:documentation>Represents a simple or compound set filter condition</xs:documentation>
</xs:annotation>
<xs:choice>
<xs:element name="setFilterAnd">
<xs:annotation>
<xs:documentation source="rn_added_7.0"/>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:group ref="setFilterCondition" minOccurs="2" maxOccurs="unbounded"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="setFilterOr">
<xs:annotation>
<xs:documentation source="rn_added_7.0"/>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:group ref="setFilterCondition" minOccurs="2" maxOccurs="unbounded"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="setFilterNot">
<xs:annotation>
<xs:documentation source="rn_added_7.0"/>
</xs:annotation>
<xs:complexType>
<xs:group ref="setFilterCondition"/>
</xs:complexType>
</xs:element>
<xs:element name="memberCaptionCondition">
<xs:annotation>
<xs:documentation source="rn_added_7.0"/>
<xs:documentation>Defines a condition against the member caption.</xs:documentation>
</xs:annotation>
<xs:complexType>
<xs:attribute name="operator" use="required">
<xs:annotation>
<xs:documentation source="doc_att_filterCondition_operator"/>
</xs:annotation>
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:enumeration value="contains">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_contains"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="beginsWith">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_beginsWith"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="endsWith">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_endsWith"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="matches">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_matches"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="containsNot">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_containsNot"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="beginsWithNot">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_beginsWithNot"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="endsWithNot">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_endsWithNot"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="matchesNot">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_matchesNot"/>
</xs:annotation>
</xs:enumeration>
</xs:restriction>
</xs:simpleType>
</xs:attribute>
<xs:attribute name="value" type="xs:string" use="required"/>
</xs:complexType>
</xs:element>
<xs:element name="stringPropertyCondition">
<xs:annotation>
<xs:documentation source="rn_added_7.0"/>
<xs:documentation>Defines a condition against a string member property. The value attribute must be provided for all operators except isNull and isNotNull.</xs:documentation>
</xs:annotation>
<xs:complexType>
<xs:all>
<xs:element ref="dmMemberProperty"/>
</xs:all>
<xs:attribute name="operator" use="required">
<xs:annotation>
<xs:documentation source="doc_att_filterCondition_operator"/>
</xs:annotation>
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:enumeration value="contains">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_contains"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="beginsWith">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_beginsWith"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="endsWith">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_endsWith"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="matches">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_matches"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="containsNot">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_containsNot"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="beginsWithNot">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_beginsWithNot"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="endsWithNot">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_endsWithNot"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="matchesNot">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_matchesNot"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="isNull"/>
<xs:enumeration value="isNotNull"/>
</xs:restriction>
</xs:simpleType>
</xs:attribute>
<xs:attribute name="value" type="xs:string" use="optional"/>
</xs:complexType>
</xs:element>
<xs:element name="numericPropertyCondition">
<xs:annotation>
<xs:documentation source="rn_added_7.0"/>
<xs:documentation>Defines a numeric condition. The condition can be for either a tuple or a member property. The value attribute must be provided for all operators except isNull and isNotNull.</xs:documentation>
</xs:annotation>
<xs:complexType>
<xs:all>
<xs:element ref="dmMemberProperty"/>
</xs:all>
<xs:attribute name="operator" use="required">
<xs:annotation>
<xs:documentation source="doc_att_filterCondition_operator"/>
</xs:annotation>
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:enumeration value="equal"/>
<xs:enumeration value="notEqual"/>
<xs:enumeration value="greaterThan"/>
<xs:enumeration value="greaterThanEqual"/>
<xs:enumeration value="lessThan"/>
<xs:enumeration value="lessThanEqual"/>
<xs:enumeration value="isNull"/>
<xs:enumeration value="isNotNull"/>
</xs:restriction>
</xs:simpleType>
</xs:attribute>
<xs:attribute name="value" type="xs:decimal" use="optional"/>
</xs:complexType>
</xs:element>
<xs:element name="tupleCondition">
<xs:annotation>
<xs:documentation source="rn_added_7.0"/>
<xs:documentation>Defines a numeric condition. The condition can be for either a tuple or a member property. The value attribute must be provided for all operators except isNull and isNotNull.</xs:documentation>
</xs:annotation>
<xs:complexType>
<xs:all>
<xs:element ref="dmTuple"/>
</xs:all>
<xs:attribute name="operator" use="required">
<xs:annotation>
<xs:documentation source="doc_att_filterCondition_operator"/>
</xs:annotation>
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:enumeration value="equal"/>
<xs:enumeration value="notEqual"/>
<xs:enumeration value="greaterThan"/>
<xs:enumeration value="greaterThanEqual"/>
<xs:enumeration value="lessThan"/>
<xs:enumeration value="lessThanEqual"/>
<xs:enumeration value="isNull"/>
<xs:enumeration value="isNotNull"/>
</xs:restriction>
</xs:simpleType>
</xs:attribute>
<xs:attribute name="value" type="xs:decimal" use="optional"/>
</xs:complexType>
</xs:element>
</xs:choice>
</xs:group>
I see that it has sub groups that are of the same type of the parent. Why does this cause a circular reference? How can I edit this XSD to not cause the error?
The same was asked on SO a while ago... this is the post, with some answers.
The solution I am proposing should be simpler, especially in your case where you can edit the XSD and the fact is the group itself fully describes the content of the element where is used.
The trick is then to reuse and implement the recusivity of your content not through group reference, but through complex type. If you compare your schema to the mine below, you'll notice how I've defined and used the complex type.
Hopefully it'll help someone else....
The refactored XSD works with XSD.exe, the class generates clean, without any error.
<?xml version="1.0" encoding="utf-8"?>
<!--W3C Schema generated by QTAssistant/W3C Schema Refactoring Module (http://www.paschidev.com)-->
<xs:schema xmlns="http://tempuri.org/XMLSchema.xsd" elementFormDefault="qualified" targetNamespace="http://tempuri.org/XMLSchema.xsd" xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:annotation>
<xs:documentation>Generated from "Set2" under "Release1"</xs:documentation>
</xs:annotation>
<xs:element name="dmTuple" type="xs:string"/>
<xs:element name="dmMemberProperty" type="xs:string"/>
<xs:complexType name="setFilterConditionList">
<xs:sequence minOccurs="2" maxOccurs="unbounded">
<xs:group ref="setFilterCondition"/>
</xs:sequence>
</xs:complexType>
<xs:group name="setFilterCondition">
<xs:choice>
<xs:element ref="setFilterAnd">
<xs:annotation>
<xs:documentation source="rn_added_7.0"/>
</xs:annotation>
</xs:element>
<xs:element ref="setFilterOr">
<xs:annotation>
<xs:documentation source="rn_added_7.0"/>
</xs:annotation>
</xs:element>
<xs:element ref="setFilterNot">
<xs:annotation>
<xs:documentation source="rn_added_7.0"/>
</xs:annotation>
</xs:element>
<xs:element name="memberCaptionCondition">
<xs:annotation>
<xs:documentation source="rn_added_7.0"/>
<xs:documentation>Defines a condition against the member caption.</xs:documentation>
</xs:annotation>
<xs:complexType>
<xs:attribute name="operator" use="required">
<xs:annotation>
<xs:documentation source="doc_att_filterCondition_operator"/>
</xs:annotation>
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:enumeration value="contains">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_contains"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="beginsWith">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_beginsWith"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="endsWith">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_endsWith"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="matches">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_matches"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="containsNot">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_containsNot"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="beginsWithNot">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_beginsWithNot"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="endsWithNot">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_endsWithNot"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="matchesNot">
<xs:annotation>
<xs:documentation source="doc_enum_memberCaptionCondition_operator_matchesNot"/>
</xs:annotation>
</xs:enumeration>
</xs:restriction>
</xs:simpleType>
</xs:attribute>
<xs:attribute name="value" type="xs:string" use="required"/>
</xs:complexType>
</xs:element>
<xs:element name="stringPropertyCondition">
<xs:annotation>
<xs:documentation source="rn_added_7.0"/>
<xs:documentation>Defines a condition against a string member property. The value attribute must be provided for all operators except isNull and isNotNull.</xs:documentation>
</xs:annotation>
<xs:complexType>
<xs:all>
<xs:element ref="dmMemberProperty"/>
</xs:all>
<xs:attribute name="operator" use="required">
<xs:annotation>
<xs:documentation source="doc_att_filterCondition_operator"/>
</xs:annotation>
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:enumeration value="contains">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_contains"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="beginsWith">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_beginsWith"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="endsWith">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_endsWith"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="matches">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_matches"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="containsNot">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_containsNot"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="beginsWithNot">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_beginsWithNot"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="endsWithNot">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_endsWithNot"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="matchesNot">
<xs:annotation>
<xs:documentation source="doc_enum_stringPropertyCondition_operator_matchesNot"/>
</xs:annotation>
</xs:enumeration>
<xs:enumeration value="isNull"/>
<xs:enumeration value="isNotNull"/>
</xs:restriction>
</xs:simpleType>
</xs:attribute>
<xs:attribute name="value" type="xs:string" use="optional"/>
</xs:complexType>
</xs:element>
<xs:element name="numericPropertyCondition">
<xs:annotation>
<xs:documentation source="rn_added_7.0"/>
<xs:documentation>Defines a numeric condition. The condition can be for either a tuple or a member property. The value attribute must be provided for all operators except isNull and isNotNull.</xs:documentation>
</xs:annotation>
<xs:complexType>
<xs:all>
<xs:element ref="dmMemberProperty"/>
</xs:all>
<xs:attribute name="operator" use="required">
<xs:annotation>
<xs:documentation source="doc_att_filterCondition_operator"/>
</xs:annotation>
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:enumeration value="equal"/>
<xs:enumeration value="notEqual"/>
<xs:enumeration value="greaterThan"/>
<xs:enumeration value="greaterThanEqual"/>
<xs:enumeration value="lessThan"/>
<xs:enumeration value="lessThanEqual"/>
<xs:enumeration value="isNull"/>
<xs:enumeration value="isNotNull"/>
</xs:restriction>
</xs:simpleType>
</xs:attribute>
<xs:attribute name="value" type="xs:decimal" use="optional"/>
</xs:complexType>
</xs:element>
<xs:element name="tupleCondition">
<xs:annotation>
<xs:documentation source="rn_added_7.0"/>
<xs:documentation>Defines a numeric condition. The condition can be for either a tuple or a member property. The value attribute must be provided for all operators except isNull and isNotNull.</xs:documentation>
</xs:annotation>
<xs:complexType>
<xs:all>
<xs:element ref="dmTuple"/>
</xs:all>
<xs:attribute name="operator" use="required">
<xs:annotation>
<xs:documentation source="doc_att_filterCondition_operator"/>
</xs:annotation>
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:enumeration value="equal"/>
<xs:enumeration value="notEqual"/>
<xs:enumeration value="greaterThan"/>
<xs:enumeration value="greaterThanEqual"/>
<xs:enumeration value="lessThan"/>
<xs:enumeration value="lessThanEqual"/>
<xs:enumeration value="isNull"/>
<xs:enumeration value="isNotNull"/>
</xs:restriction>
</xs:simpleType>
</xs:attribute>
<xs:attribute name="value" type="xs:decimal" use="optional"/>
</xs:complexType>
</xs:element>
</xs:choice>
</xs:group>
<xs:element name="setFilterAnd" type="setFilterConditionList"/>
<xs:element name="setFilterOr" type="setFilterConditionList"/>
<xs:element name="setFilterNot">
<xs:complexType>
<xs:group ref="setFilterCondition"/>
</xs:complexType>
</xs:element>
</xs:schema>