Rename many columns dynamically in Power Query

[Anonymous]

Hey

I am currently working on renamining several columns (around 60 columns) at once dynamically and kindly ask for help if there is any more efficient way of writing the code in the step. Right now I am inserting the code as follows:

= Table.RenameColumns(#"Promoted Headers",{{Table.ColumnNames(#"Promoted Headers"){52}, "wk1"}, {Table.ColumnNames(#"Promoted Headers"){53}, "wk2"}, {Table.ColumnNames(#"Promoted Headers"){54}, "wk3"}, {Table.ColumnNames(#"Promoted Headers"){55}, "wk4"}}).... etc

Is it not possible to write some sort of loop instead for this to make the code look better? 🙂

All help is appreciated!

Best wishes

/Sammy

[Anonymous]

Awesome thanks!

[AlexisOlson · Accepted solution]

I'd recommend something like this:

let
    <...>
    #"Promoted Headers" = <...>,
    ColNames = List.Buffer(Table.ColumnNames(#"Promoted Headers")),
    ReplaceList = List.Transform({1..4}, each {ColNames{_+51}, "wk" & Number.ToText(_)}),
    #"Renamed Columns" = Table.RenameColumns(#"Promoted Headers", ReplaceList)
in
    #"Renamed Columns"

This stores the column names as a list and then transforms {1,2,3,4} into:

{
  {ColNames{1+51}, "wk" & Number.ToText(1)},
  {ColNames{2+51}, "wk" & Number.ToText(2)},
  {ColNames{3+51}, "wk" & Number.ToText(3)},
  {ColNames{4+51}, "wk" & Number.ToText(4)}
} =
{
  {ColNames{52}, "wk1"},
  {ColNames{53}, "wk2"},
  {ColNames{54}, "wk3"},
  {ColNames{55}, "wk4"}
}