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MMoll's avatar
MMoll
Frequent Visitor
3 years ago

Need help iterating over all columns

I have columns constaining a mix of records and lists. I need to convert them all to lists, collapse them into a table, and then expand them. (Thus extracting the contents of each list without disrup...
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MMoll's avatar
MMoll
Frequent Visitor
3 years ago

Yes; that's exactly what I'm trying to do. But I need the list of columns (and/or column names) to be dynamic so I can set it up as a function.

ThxAlot's avatar
ThxAlot
Super User
3 years ago

 

let
    fx_TableTransfermation = (t as table) =>
        let
            #"Combined Columns" = Table.CombineColumns(
                t,
                Table.ColumnNames(t), each Table.FromColumns(List.Transform(_, each if Value.Is(_, type list) then _ else {_})),
                "Combined"),
            #"Expanded Combined" = Table.ExpandTableColumn(#"Combined Columns", "Combined", List.Transform({1..Table.ColumnCount(t)}, each "Column"&Text.From(_)))
        in
            #"Expanded Combined",

    Source = Table.FromColumns({{null,"ac",{1..3}},{{"A".."D"},123,""},{1,{"u".."z"}}}),
    Invocation = fx_TableTransfermation(Source)
in
    Invocation