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II1154
Frequent Visitor

count the number of duplicates

Bonjour je cherche un moyen avec List de trouver le nombre de doublons (nb.if) sans passer par le doublon du tableau sur powerquery, merci d’avance

occurrencenb.SI
X12
X24
X33
X41
X51
X62
X24
X33
X91
X101
X12
X121
X24
X33
X62
X24
1 ACCEPTED SOLUTION
ronrsnfld
Super User
Super User

  • Add an Index Column
  • Group by occurrence
    • Aggregate by "All Rows"
    • Aggregate by "Count"
  • Expand the "All Rows"
  • Sort back to original order using the Index column

Another method that may be less efficient is to add a custom column with the formula:

  List.Count(List.Select(#"Changed Type"[occurrence], (li)=> li = [occurrence]))

 

To duplicate, paste the code below into a blank query:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WijBUitUBUkYQyhhCmUAoUwhlhk2JJYQyNIDSUMoIm1qEAbEA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [occurrence = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"occurrence", type text}}),

    #"Added Custom" = Table.AddColumn(#"Changed Type", "Count", each 
        List.Count(
            List.Select(#"Changed Type"[occurrence], 
                (li)=> li = [occurrence])), Int64.Type)
in
    #"Added Custom"

ronrsnfld_0-1678069091224.png

 

 

 

View solution in original post

4 REPLIES 4
theov
Advocate III
Advocate III

In old days it was done by EARLIER function but now you can use varibales to do it.

You can watch this video too.

https://www.youtube.com/watch?v=JI-QUASKuUw

 

ronrsnfld
Super User
Super User

  • Add an Index Column
  • Group by occurrence
    • Aggregate by "All Rows"
    • Aggregate by "Count"
  • Expand the "All Rows"
  • Sort back to original order using the Index column

Another method that may be less efficient is to add a custom column with the formula:

  List.Count(List.Select(#"Changed Type"[occurrence], (li)=> li = [occurrence]))

 

To duplicate, paste the code below into a blank query:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WijBUitUBUkYQyhhCmUAoUwhlhk2JJYQyNIDSUMoIm1qEAbEA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [occurrence = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"occurrence", type text}}),

    #"Added Custom" = Table.AddColumn(#"Changed Type", "Count", each 
        List.Count(
            List.Select(#"Changed Type"[occurrence], 
                (li)=> li = [occurrence])), Int64.Type)
in
    #"Added Custom"

ronrsnfld_0-1678069091224.png

 

 

 

II1154
Frequent Visitor

too bad that with a line in (list.... power query we can't have that, in powerbi in my case it can't work

Migasuke
Memorable Member
Memorable Member

Hi @II1154 ,

This is not possible.
You could duplocicate the table / list and apply Group By. Then merge the original table with group by table to see number of duplicates.
If you can, try solution in DAX instead.

Ce n'est pas possible. Vous pouvez dupliquer le tableau/la liste et appliquer Grouper par. Fusionnez ensuite la table d'origine avec groupe par table pour voir le nombre de doublons. Si vous le pouvez, essayez plutôt la solution dans DAX.

 



If my answer was helpful please give me a Kudos or even accept as a Solution.

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