Append column names in nested table from value of another column

[don]

Hello everyone, could I please get help from  anyone on how to rename all column names from the tables in "Custom" column and append them with the value from column "Code"

[Vijay_A_Verma · Accepted solution]

Use this code. Replace #"Grouped Rows" with your previous step name

= Table.FromRecords(Table.TransformRows(#"Grouped Rows", (r)=> [Code = r[Code], Custom = Table.TransformColumnNames(r[Custom], (x)=>x&Text.From(r[Code]))]))

[don]

Thank you Vijay, it worked great.

Is there a way to rename columns that name which contains specific text, let's say rename columns that contains "abc" in the header only

[dufoq3]

Hi @don, check this. Remove ", Comparer.OrdinalIgnoreCase" from the code if you want case sensitive check.

let
    Source = #table(type table[Code=Int64.Type, Custom=table], {
        {6100, #table({"Column10", "Test abc 1", "Column20"}, {{1,2,3}})},
        {6200, #table({"Column10", "Test abc", "A_Abc_B"}, {{4,5,6}})}
    }),
    Ad_Renamed = Table.AddColumn(Source, "Renamed", each Table.RenameColumns([Custom], 
        [ a = List.Select(Table.ColumnNames([Custom]), (x)=> Text.Contains(x, "abc", Comparer.OrdinalIgnoreCase)),
          b = List.Zip({ a, List.Transform(a, (x)=> x & Text.From([Code])) })
        ][b]),
    type table)
in
    Ad_Renamed