MS SQL iterate through XML with default namespaces

Question

Based on this reply

So for example, we have XML like this

<parent_node >
   <category>Low</category>
   <category>Medium</category>
   <category>High</category>
</parent_node>

and everything is good. But in my case i have a default XML namespace here, so my XML looks like this:

<parent_node xmlns="http://schemas.datacontract.org/2004/07/MonitorWang.Core.Interfaces.Entities">
   <category>Low</category>
   <category>Medium</category>
   <category>High</category>
</parent_node>

and now it doesn't work.

Entire script:

DECLARE @XmlVariable XML = '<parent_node xmlns="http://schemas.datacontract.org/2004/07/MonitorWang.Core.Interfaces.Entities">
                              <category>Low</category>
                              <category>Medium</category>
                              <category>High</category>
                            </parent_node>'

  SELECT 
     XTbl.Cats.value('.', 'varchar(50)')
  FROM 
     @XmlVariable.nodes('/parent_node/category') AS XTbl(Cats)

Please, advice, how to fix it?

Answer 1

If you want to account for the default namespace throughout the document then you can use something like....

    DECLARE @XmlVariable XML = '<parent_node xmlns="http://schemas.datacontract.org/2004/07/MonitorWang.Core.Interfaces.Entities">
                              <category>Low</category>
                              <category>Medium</category>
                              <category>High</category>
                            </parent_node>'

  SELECT 
     XTbl.Cats.value('.', 'varchar(50)')
  FROM 
     @XmlVariable.nodes('declare default element namespace "http://schemas.datacontract.org/2004/07/MonitorWang.Core.Interfaces.Entities"; /parent_node/category') AS XTbl(Cats)

Alternatively, you can declare the namespace in the xquery string and refer to it in the XPath if the default namespace is on a child element...

@XmlVariable.nodes('declare namespace c="http://schemas.datacontract.org/2004/07/MonitorWang.Core.Interfaces.Entities"; /parent_node/c:category')

There is more detail here .