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Dom33
Regular Visitor

language M substring ? in data query

Hi,

In my json input file I have a very large column (data_found in my request) and it is very long to load data in PowerBI.

I just want an extract of this large columns (the first 100 characters for example).

In the advanced editor, is it possible to add M language instructions to do that ?

 

Thanks

 

Dominique

 

let
    Source = Json.Document(File.Contents("C:\carto\results.json")),
    phone = Source[phone_number],
    columns = phone[columns],
    #"Converted to Table" = Table.FromList(columns, Splitter.SplitByNothing(), 1, null, ExtraValues.Error),
    #"Expanded Column1" = Table.ExpandRecordColumn(#"Converted to Table", "Column1", {"location", "numbers_of_rows_analyzed", "percentage_of_personnal_data", "data_found"}, {"location", "numbers_of_rows_analyzed", "percentage_of_personnal_data", "data_found"}),
    #"Changed Type" = Table.TransformColumnTypes(#"Expanded Column1",{{"data_found", type text}})
in
    #"Changed Type"

1 ACCEPTED SOLUTION
MarcelBeug
Community Champion
Community Champion

No need for the Advanced Editor.

 

Select your column - on the "Transform" tab: Extract - First Characters - 100 - OK.

Specializing in Power Query Formula Language (M)

View solution in original post

2 REPLIES 2
v-ljerr-msft
Microsoft Employee
Microsoft Employee

Hi @Dom33,

 

Have you tried the solution provided by @MarcelBeug above? Does it work in your scenario? If it works, could you accept it as solution to close this thread?

 

If you still have any question on this issue, feel free to post here. Smiley Happy

 

Regards

MarcelBeug
Community Champion
Community Champion

No need for the Advanced Editor.

 

Select your column - on the "Transform" tab: Extract - First Characters - 100 - OK.

Specializing in Power Query Formula Language (M)

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