Statically ambiguous or query-style paths not supported in step path

[Roger L Costello]

Hi Folks,

I tried Mike's suggestion to avoid the UPA error: precede the element with a 
uniquely named empty element, e.g.,

<xs:element name="record">
    <xs:complexType>
        <xs:sequence>
            <xs:element name="Section_Code" type="fixedLength_string" 
dfdl:length="1"/>
            <xs:choice dfdl:choiceDispatchKey="{Section_Code}">
                <xs:sequence dfdl:choiceBranchKey="D">
                    <xs:element name="Unique_Name_1" type="xs:string" 
dfdl:lengthKind="explicit" dfdl:length="0"/>
                    <xs:element name="Subsection_Code" 
type="fixedLength_string" dfdl:length="1"/>
                </xs:sequence>
                <xs:sequence dfdl:choiceBranchKey="E">
                    <xs:element name="Unique_Name_2" type="xs:string" 
dfdl:lengthKind="explicit" dfdl:length="0"/>
                    <xs:element name="Subsection_Code" 
type="fixedLength_string" dfdl:length="1"/>
                </xs:sequence>
            </xs:choice>
        </xs:sequence>
    </xs:complexType>
</xs:element>

However, that results in Daffodil generating these warning messages:

[warn] Schema Definition Warning: Statically ambiguous or query-style paths not 
supported in step path: '{}Subsection_Code'. Matches are at locations: ...

What is that all about? How to get rid of them?

/Roger