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T-SQL scorre attraverso la colonna di dati XML per derivare un insieme univoco di percorsi

L'approccio obsoleto con FROM OPENXML potrebbe essere un'opzione qui. Controlla questa risposta .

A questo link troverai una funzione pubblicata di volta in volta da John Cappelletti, che distruggerà qualsiasi XML (crediti sotto il codice della funzione).

Ma non sono sicuro di cosa stai veramente cercando di ottenere... Perché hai bisogno del percorso? Se sei interessato ai valori di tutti i nodi target, potresti fare qualcosa del genere (ricerca approfondita con // non ha bisogno dell'esatto XPath )

 SELECT t.value(N'(text())[1]','nvarchar(max)')
 FROM @xml.nodes('//target') AS A(t);

Se hai davvero bisogno di tutto e di tutto puoi controllare questo:

CREATE FUNCTION [dbo].[udf-XML-Hier](@XML xml)

Returns Table 
As Return

with  cte0 as ( 
                  Select Lvl       = 1
                        ,ID        = Cast(1 as int) 
                        ,Pt        = Cast(NULL as int)
                        ,Element   = x.value('local-name(.)','varchar(150)')
                        ,Attribute = cast('' as varchar(150))
                        ,Value     = x.value('text()[1]','varchar(max)')
                        ,XPath     = cast(concat(x.value('local-name(.)','varchar(max)'),'[' ,cast(Row_Number() Over(Order By (Select 1)) as int),']') as varchar(max))
                        ,Seq       = cast(1000000+Row_Number() over(Order By (Select 1)) as varchar(max))
                        ,AttData   = x.query('.') 
                        ,XMLData   = x.query('*') 
                  From   @XML.nodes('/*') a(x) 
                  Union  All
                  Select Lvl       = p.Lvl + 1 
                        ,ID        = Cast( (Lvl + 1) * 1024 + (Row_Number() Over(Order By (Select 1)) * 2) as int ) * 10
                        ,Pt        = p.ID
                        ,Element   = c.value('local-name(.)','varchar(150)')
                        ,Attribute = cast('' as varchar(150))
                        ,Value     = cast( c.value('text()[1]','varchar(max)') as varchar(max) ) 
                        ,XPath     = cast(concat(p.XPath,'/',c.value('local-name(.)','varchar(max)'),'[',cast(Row_Number() Over(PARTITION BY c.value('local-name(.)','varchar(max)') Order By (Select 1)) as int),']') as varchar(max) )
                        ,Seq       = cast(concat(p.Seq,' ',10000000+Cast( (Lvl + 1) * 1024 + (Row_Number() Over(Order By (Select 1)) * 2) as int ) * 10) as varchar(max))
                        ,AttData   = c.query('.') 
                        ,XMLData   = c.query('*') 
                  From   cte0 p 
                  Cross  Apply p.XMLData.nodes('*') b(c) 
              )
    , cte1 as (   
                  Select R1 = Row_Number() over (Order By Seq),A.*
                  From  (
                          Select  Lvl,ID,Pt,Element,Attribute,Value,XPath,Seq From cte0
                          Union All
                          Select Lvl       = p.Lvl+1
                                ,ID        = p.ID + Row_Number() over (Order By (Select NULL)) 
                                ,Pt        = p.ID
                                ,Element   = p.Element
                                ,Attribute = x.value('local-name(.)','varchar(150)')
                                ,Value     = x.value('.','varchar(max)')
                                ,XPath     = p.XPath + '/@' + x.value('local-name(.)','varchar(max)')
                                ,Seq       = cast(concat(p.Seq,' ',10000000+p.ID + Row_Number() over (Order By (Select NULL)) ) as varchar(max))
                          From   cte0 p 
                          Cross  Apply AttData.nodes('/*/@*') a(x) 
                        ) A 
               )

Select A.R1
      ,R2  = IsNull((Select max(R1) From cte1 Where Seq Like A.Seq+'%'),A.R1)
      ,A.Lvl
      ,A.ID
      ,A.Pt
      ,A.Element
      ,A.Attribute
      ,A.XPath
      ,Title = Replicate('|---',Lvl-1)+Element+IIF(Attribute='','','@'+Attribute)
      ,A.Value
 From  cte1 A

/*
Source: http://beyondrelational.com/modules/2/blogs/28/posts/10495/xquery-lab-58-select-from-xml.aspx

Taken from John Cappelletti: https://stackoverflow.com/a/42729851/5089204

Declare @XML xml='<person><firstname preferred="Annie" nickname="BeBe">Annabelle</firstname><lastname>Smith</lastname></person>'
Select * from [dbo].[udf-XML-Hier](@XML) Order by R1
*/
GO 

DECLARE @xml XML=
'<log>
  <clients>
   <client>
    <section name ="Apps"> 
     <questions>
      <groupone>
       <question>
        <target>Age</target>
       </question>
       <question>
        <target> Height</target>
       </question>
       <question>
        <target> Weight</target>
       </question>
      </groupone>
      <grouptwo name = "exercise">
       <wording>what is your name</wording>
        <question>
         <id>1</id>
         <target>def</target>
        </question>
      </grouptwo>
     </questions>
    </section>
   </client>
  </clients>
 </log>';

 SELECT * FROM dbo.[udf-XML-Hier](@xml);
GO