Skip to main content
cancel
Showing results for 
Search instead for 
Did you mean: 

July 7 - July 17 | Round 2 of the Power BI Dataviz World Championships. Don't miss your chance! Learn more

Reply
Anonymous
Not applicable

Dynamic Column Names

I have a Web API endpoint which I want to pull data from it. It is protected with OAuth2.
Right now I can successfully pull the data from it but I have to specify the column names.
I want the column names to be dynamic.


The below code is working good:

let
GetAuth = Web.Contents("https://localhost/token",
[
Headers = [#"Accept"="application/json",
#"Content-Type"="application/x-www-form-urlencoded;charset=UTF-8"],
Content = Text.ToBinary("username=username&password=password&grant_type=password")
]),
FormatAuthAsJson = Json.Document(GetAuth),
access_token = FormatAuthAsJson[access_token],

ReportData = Json.Document(Web.Contents("https://localhost/api/Search",
[
Headers=[Authorization="bearer "&access_token,
#"Content-Type"="application/json; charset=utf-8"]
,Content = Text.ToBinary("{""SearchCriteria"":""test""}")
])),
#"Converted Data To Table" = Table.FromList(ReportData, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
#"Expanded Report Data" = Table.ExpandRecordColumn(#"Converted Data To Table", "Column1", { "Id", "Name", "Description" })

in
#"Expanded Report Data"


When I change #"Expanded Report Data" to be like that:
#"Expanded Report Data" = Table.ExpandTableColumn(#"Converted Data To Table", "Column1", List.Union(List.Transform(#"Converted Data To Table"[Column1], each Table.ColumnNames(_))))


I got this error:
Expression.Error: We cannot convert a value of type Record to type Table.

 

 

Any help will be appricaited?

1 ACCEPTED SOLUTION
Jimmy801
Community Champion
Community Champion

Hello

 

substitude this code

#"Converted Data To Table" = Table.FromList(ReportData, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
#"Expanded Report Data" = Table.ExpandRecordColumn(#"Converted Data To Table", "Column1", { "Id", "Name", "Description" })

with this one

#"Converted Data To Table" = Table.FromList(ReportData, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
UniqueRecordNames = List.Union( List.Transform(#"Converted Data To Table"[Column1], each  Record.ToTable(_)[Name])),
#"Expanded Report Data" = Table.ExpandRecordColumn(#"Converted Data To Table", "Column1", UniqueRecordNames )

 this should to the trick. Was not able to test your code, but it should work

Have fun

Jimmy

View solution in original post

2 REPLIES 2
Jimmy801
Community Champion
Community Champion

Hello

 

substitude this code

#"Converted Data To Table" = Table.FromList(ReportData, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
#"Expanded Report Data" = Table.ExpandRecordColumn(#"Converted Data To Table", "Column1", { "Id", "Name", "Description" })

with this one

#"Converted Data To Table" = Table.FromList(ReportData, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
UniqueRecordNames = List.Union( List.Transform(#"Converted Data To Table"[Column1], each  Record.ToTable(_)[Name])),
#"Expanded Report Data" = Table.ExpandRecordColumn(#"Converted Data To Table", "Column1", UniqueRecordNames )

 this should to the trick. Was not able to test your code, but it should work

Have fun

Jimmy

Anonymous
Not applicable

That is perfect @Jimmy801  thanks a million.

Helpful resources

Announcements
FabCon and SQLCon Barcelona 2026

FabCon & SQLCon – Barcelona 2026

Join us in Barcelona for FabCon and SQLCon, the Fabric, Power BI, SQL, and AI community event. Save €200 with code FABCMTY200.

60 days of Data Days Carousel

Data Days 2026

Join Fabric Data Days 2026: 60 days of free live/on-demand sessions, challenges, study groups, and certification opportunities.

Power BI DataViz World Championships carousel

Power BI DataViz World Championships - June 2026

A new Power BI DataViz World Championship is coming this June! Don't miss out on submitting your entry.