XML Schema Collection breaks xquery - sql

Question

The script below can be used to show an example of the problem I have. The script will return an error "There is no element named 'this'".
If I change the declaration of the #XML variable so it is untyped XML (replace the line DECLARE #XML XML(Test) with DECLARE #XML XML), I do not get the error, but get the expected result instead.
Why do I get the error when using the Schema collection and how can I avoid it - I want to fill a table column with properly typed xml, but I'm having trouble getting my data back out of the column.
IF EXISTS (SELECT name FROM sys.xml_schema_collections WHERE name = 'test') DROP XML SCHEMA COLLECTION Test
CREATE XML SCHEMA COLLECTION Test AS
'<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:t="http://tempuri.org/this.xsd"
targetNamespace="http://tempuri.org/this.xsd"
elementFormDefault="qualified">
<xsd:element name ="this">
<xsd:complexType>
<xsd:sequence>
<xsd:element name="What" minOccurs="1" maxOccurs="1" >
<xsd:simpleType>
<xsd:restriction base ="xsd:string">
<xsd:enumeration value ="01."/>
<xsd:enumeration value ="02."/>
<xsd:enumeration value ="03."/>
<xsd:enumeration value ="04."/>
</xsd:restriction>
</xsd:simpleType>
</xsd:element>
<xsd:element name="When" minOccurs="1" maxOccurs="1" >
<xsd:simpleType>
<xsd:restriction base ="xsd:string">
<xsd:enumeration value ="01."/>
<xsd:enumeration value ="02."/>
</xsd:restriction>
</xsd:simpleType>
</xsd:element>
<xsd:element name="Outcome" minOccurs="1" maxOccurs="1" >
<xsd:simpleType>
<xsd:restriction base ="xsd:string">
<xsd:enumeration value ="one"/>
<xsd:enumeration value ="two"/>
<xsd:enumeration value ="whatever"/>
<xsd:enumeration value =""/>
</xsd:restriction>
</xsd:simpleType>
</xsd:element>
</xsd:sequence>
</xsd:complexType>
</xsd:element>
</xsd:schema>'
GO
DECLARE #XML XML(Test)
SET #XML =
'<this xmlns="http://tempuri.org/this.xsd">
<What>02.</What>
<When>01.</When>
<Outcome></Outcome>
</this>'
SELECT #XML
SELECT
Field.value('What[1]','VARCHAR(100)')
FROM #Xml.nodes('/this') AS this(Field)

Answer 1

The problem is your namespace declaration: <this xmlns="http://tempuri.org/this.xsd">. Everything in that XML snippet belongs to the namespace http://tempuri.org/this.xsd. Your query used the unqualified name for this and What. Use this instead:
;WITH XMLNAMESPACES (
'http://tempuri.org/this.xsd' as t
)
SELECT
Field.value('t:What[1]','VARCHAR(100)')
FROM #Xml.nodes('/t:this') AS this(Field)