Extracting a SharePoint List Person Picker with empty values

[DavelinaJolie]

Hi,

I'm currently working on creating a dashboard which uses a SharePoint Online List. The list uses a person picker for the "Assigned to" field.

What I want to do is extract the [title] field where multiple users exist and use a comma separator. I'm using the below M code for this. However it generates Errors where a user is not selected in the List. Is there a way to handle the blanks where these occur?

= Table.TransformColumns(#"...", {"Assigned to", each Text.Combine(List.Transform(Table.TransformRows(_, each [title]), Text.from), ", "), type text})

Sorry, I should say the error is

Expression.Error: We cannot convert the value null to type Table. So I gather that because the field is null that it can't perform the action of conversion?

[DavelinaJolie · Accepted solution]

I think I found a different solution.

I adapted this:

https://community.powerbi.com/t5/Desktop/Extract-table-from-column/td-p/1022979

To create a new column but used Table.SelectColumns to specify the exact column I wanted as so:

if [Assigned to] is table 

then 

  Text.Combine(

    List.Transform(

      List.Combine(Table.ToRows(Table.SelectColumns([Assigned to], "title"])))

      , each Text.From(_)

      )

    ,","

    )

else [Assigned to]

Which returns the items in the specified column delimited by comma, unless the original column value is null, in which case it returns a null.