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

Compete to become Power BI Data Viz World Champion! First round ends August 18th. Get started.

Reply
Anonymous
Not applicable

Expression.Error: We cannot convert a value of type List to type Number.

Hi All,

 

getting this error when i perform value combine operation for multiple rows.

Expression.Error: We cannot convert a value of type List to type Number.
Details:
Value=[List]
Type=[Type]

Data steps:
The columns are in text data type, i checked changing the data type to any but still did not work.
All columns are mix of alphanumeric plus blank data. I also did remove blank data but same error.

= Table.Group(#"source_previous step", {"ID"},
{"ID Type", each Text.Combine(List.Distinct([ID Type]), ";"), type nullable text},
{"ID Number", each Text.Combine(List.Distinct([ID Number]), ";"), type nullable text}
)

 

no error when i add the first line i.e;
= Table.Group(#"source_previous step",  {"ID"},
{"ID Type", each Text.Combine(List.Distinct([ID Number]), ";"), type nullable text},

but when i add the second line the error pops in.
ie, {"ID Number", each Text.Combine(List.Distinct([ID Type]), ";"), type nullable text}

3 REPLIES 3
Ahmedx
Super User
Super User

try this

Table.Group(#"source_previous step", {"ID"},
{"ID Type", (x)=> Text.Combine(List.Distinct(x[ID Type]), ";"), type nullable text},
{"ID Number", (x)=> Text.Combine(List.Distinct(x[ID Number]), ";"), type nullable text}
)
Anonymous
Not applicable

Cannot share the file.
ID, ID Number, ID Type are columns.
For ID Type same code works without issue but for others i get this error, even though all data types are converted to text in previous steps

Ahmedx
Super User
Super User

[ID Number] is a column right?
what's in the column, list?
share the file

Helpful resources

Announcements
August Power BI Update Carousel

Power BI Monthly Update - August 2025

Check out the August 2025 Power BI update to learn about new features.

August 2025 community update carousel

Fabric Community Update - August 2025

Find out what's new and trending in the Fabric community.

Top Solution Authors