Properly pivot an XML column with XQuery

All we need is an easy explanation of the problem, so here it is.

I would like to pivot the attributes and values of an SQL XML column and display it in an ordered columns and rows format.

To get started, this is what the XML column looks like in SQL:

<Model xmlns:dsc="ModelDescriptive" xmlns:draw="ModelDraw" xmlns:display="Display" xmlns:thd="Model3D">
  <dsc:Model name="15DE">
    <dsc:Defs>
      <dsc:Materials>
        <dsc:Material ref="E-HD-AnoAno" baseRef="E-HD" type="rod" productionGroup="OPTION" />
        <dsc:Material ref="E-3L44A-CLEAR" baseRef="E-3L44A" type="piece" productionGroup="OPTION" />
        <dsc:Material ref="R-TH01" baseRef="R-TH-TH" type="rod" productionGroup="ASSEMBLY" />
        <dsc:Material ref="M-TH05" baseRef="M-TH" type="meter" productionGroup="MOLDING" />
      </dsc:Materials>
    </dsc:Defs>
  </dsc:Model>
</Model>

…and here is my query :

 SELECT
      x.y.value('local-name(..)', 'VARCHAR(MAX)') ParentElementName
     ,x.y.value('local-name(.)', 'VARCHAR(MAX)') Attribut
     ,x.y.value('.', 'VARCHAR(MAX)') Value
     ,Row_number() Over(Partition by x.y.value('local-name(..)', 'VARCHAR(MAX)') order by x.y.value('local-name(..)', 'VARCHAR(MAX)') ASC)  as rn
 FROM @xmlDescriptive.nodes('//*[text()], //@*') AS x(y)
 WHERE x.y.value('local-name(..)', 'VARCHAR(MAX)')= 'Material'
 ORDER BY x.y.value('local-name(..)', 'VARCHAR(MAX)')

I get an interesting result using the Nodes method of XQuery and filtering only on the material from the bill of material (BOM).

However, I would like to present the data in a standardized fashion.

The first result I get looks like this:

Properly pivot an XML column with XQuery

Then I transform this result to rotate it using the Pivot method. Here is my method of trying to pivot my information:

 SELECT [ref], [baseRef], [type], [productionGroup]
 FROM 
 (
     SELECT
          x.y.value('local-name(..)', 'VARCHAR(MAX)') ParentElementName
         ,x.y.value('local-name(.)', 'VARCHAR(MAX)') Attribut
         ,x.y.value('.', 'VARCHAR(MAX)') Valeur
         ,CAST(Row_number() Over(Partition by x.y.value('local-name(.)', 'VARCHAR(MAX)') order by x.y.value('local-name(..)', 'VARCHAR(MAX)') ASC) as varchar(10)) as rn
     FROM @xmlDescriptive.nodes('//@*') AS x(y)
     WHERE x.y.value('local-name(..)', 'VARCHAR(MAX)')= 'Material'
    
 ) d
 pivot
 (
   max(Valeur)
   FOR Attribut in ([ref], [baseRef], [type], [productionGroup])
 ) piv 

And I find my result in are unordered. The column ref does not match my baseRef, type and productGroup columns:

Properly pivot an XML column with XQuery

I am a little confused. I would like to have my result formatted this way but ordered. What is wrong with my reasoning?

I would like my result to be presented like this:

Properly pivot an XML column with XQuery

How to solve :

I know you bored from this bug, So we are here to help you! Take a deep breath and look at the explanation of your problem. We have many solutions to this problem, But we recommend you to use the first method because it is tested & true method that will 100% work for you.

Method 1

I’m probably missing the point of your question but here is what I would do to get the result you are looking for.

with xmlnamespaces('ModelDescriptive' as dsc)
select M.X.value('@ref', 'varchar(max)') as ref,
       M.X.value('@baseRef', 'varchar(max)') as baseRef,
       M.X.value('@type', 'varchar(max)') as type,
       M.X.value('@productionGroup', 'varchar(max)') as productionGroup
from @xmlDescriptive.nodes('//dsc:Material') as M(X);

Your use of local-name() and //*[text()], //@*' suggests you want some kind of generic pivot but you use Material and the attribute names hard coded in the query so I don’t know why you went down that road.

Note: Use and implement method 1 because this method fully tested our system.
Thank you 🙂

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

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