Error "The name "soap" does not denote a namespace" if i try to parse XML in T-sql - sql

Question

When i try to parse XML in T-sql I get error "The name "soap" does not denote a namespace"
This is my XML and query. Answer, please, how can I parse such XML. Thanks.
DECLARE #xml xml
SET #xml =
'<soap:Envelope xmlns:soap=http://schemas.xmlsoap.org/soap/envelope/>
<soap:Body>
<GetWebLinkResponse xmlns=http://test.org/ xmlns:ns2=http://schemas.datacontract.org/2004/07/.Configuration xmlns:ns3=http://schemas.datacontract.org/2004/07/.Configuration.Results xmlns:ns4=http://schemas.microsoft.com/2003/10/Serialization/>
<GetWebLinkResult>
<ns3:Error>
<ns2:Id>0</ns2:Id>
<ns2:Text>Success.</ns2:Text>
</ns3:Error>
<ns3:Url>
https://example.com&content=true
</ns3:Url>
</GetWebLinkResult>
</GetWebLinkResponse>
</soap:Body>
</soap:Envelope>'
SELECT
-- n.value('(./Code/text())[1]','int') as CODE
--,
n.value('ns3:Url','varchar(1000)')as NAME
FROM #xml.nodes('/soap:Envelope/soap:Body/GetWebLinkResponse/GetWebLinkResult') as a(n)

Answer 1

First of all - your XML is invalid - your namespace definitions must be in double quotes:
DECLARE #xml xml
SET #xml =
'<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
<soap:Body>
<GetWebLinkResponse xmlns="http://test.org/" xmlns:ns2="http://schemas.datacontract.org/2004/07/.Configuration" xmlns:ns3="http://schemas.datacontract.org/2004/07/.Configuration.Results" xmlns:ns4="http://schemas.microsoft.com/2003/10/Serialization/">
<GetWebLinkResult>
<ns3:Error>
<ns2:Id>0</ns2:Id>
<ns2:Text>Success.</ns2:Text>
</ns3:Error>
<ns3:Url>
https://example.com&content=true
</ns3:Url>
</GetWebLinkResult>
</GetWebLinkResponse>
</soap:Body>
</soap:Envelope>';
Once you've corrected that, you'll need to define all relevant XML namespaces for your T-SQL query. Relevant XML namespaces are all explicitly used namespaces (like soap: and ns3:), as well as default namespaces like the xmlns="http://test.org/" on your <GetWebLinkResponse> node.
When you declare them all - the T-SQL query should work:
WITH XMLNAMESPACES('http://schemas.xmlsoap.org/soap/envelope/' AS soap,
'http://schemas.datacontract.org/2004/07/.Configuration.Results' as ns3,
DEFAULT 'http://test.org/')
SELECT
n.value('(ns3:Url)[1]', 'varchar(1000)') AS NAME
FROM
#xml.nodes('/soap:Envelope/soap:Body/GetWebLinkResponse/GetWebLinkResult') as a(n)