New to Power Query - Duplicate All Columns

[Mark_Desmarais]

Hello, I have a fairly simple problem I'm not sure how to approach.

I have a table in Power Query and I want to duplicate all the columns (and modify their names) without having to do it manually as new columns are added.

For example, I have:

Column1	Column2	Column3

And I want it to become

Column1A	Column1B	Column2A	Column2B	Column3A	Column3B

I assume the answer here is something like, "get a list of all the column names, run duplicate column on all of them, then rename them" but I'm not sure how to approach that.

[#2 · Accepted solution]

@Mark_Desmarais 

You may generate script like this

let
    Source = Excel.CurrentWorkbook(){[Name="Table1"]}[Content],

    names = Table.ColumnNames (Source),
    namesA = List.Transform( names, (q) => q & "A"),

    ourColumns = Table.ToColumns(Source),
    tableWithDuplicatedColumns = Table.FromColumns(
        ourColumns & ourColumns,
        names & namesA)
in
    tableWithDuplicatedColumns

[#3]

@Sergei Baklan Thank you very much, this is what I was looking for. I appreciate your understanding of the problem.

The only issue I have at the moment is that the columns in this solution are actually organized like this:

Column1A	Column2A	Column3A	Column1B	Column2B	Column3B

Where I'd prefer them like this:

Column1A	Column1B	Column2A	Column2B	Column3A	Column3B

Is there an elegant way to write the step with Table.FromColumns where the columns where the two sets of columns are merged in alternating columns?

Thank you.

[#4]

@Mark_Desmarais 

That could be like

let
    Source = Excel.CurrentWorkbook(){[Name="Table1"]}[Content],

    names = Table.ColumnNames (Source),
    namesA = List.Transform( names, (q) => q & "A"),

    ourColumns = Table.ToColumns(Source),
    tableWithDuplicatedColumns = Table.FromColumns(
        List.Union( List.Zip( {ourColumns, ourColumns} ) ),
        List.Union( List.Zip( {names, namesA} ) )
    )
in
    tableWithDuplicatedColumns

based on previous sample