Perulangan T-SQL melalui kolom data XML untuk mendapatkan kumpulan jalur yang unik

Pendekatan usang dengan FROM OPENXML mungkin bisa jadi pilihan disini. Periksa jawaban ini .

Di tautan ini Anda akan menemukan fungsi yang diposkan John Cappelletti dari waktu ke waktu, yang akan menghancurkan XML apa pun (kredit di bawah kode fungsi).

Tapi saya tidak yakin, apa yang sebenarnya ingin Anda capai... Mengapa Anda membutuhkan jalan? Jika Anda tertarik dengan nilai semua node target, Anda dapat melakukan sesuatu seperti ini (pencarian mendalam dengan // tidak memerlukan XPath yang tepat )

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

Jika Anda benar-benar membutuhkan semua dan segalanya Anda dapat memeriksa ini:

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