Dynamic column name based on a column value coming from a different unrelated table

Hi Anonymous ,

Please try:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("RY85DoAwDAT/4prC3LSEMomUkkNpQIIe+L9YCE6mWEujabws1DPnlFGvBmzOzDi3QD77igJynGZsGYpDkKKEVEqlYhOkqCC11tgmFGtEkhrWGIOtQ3JFJGlgnXPYLiTnjwQtnLX2f+Yt9gR5/wA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Column1 = _t, Column2 = _t, Column3 = _t, Column4 = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Column1", type text}, {"Column2", type text}, {"Column3", Int64.Type}, {"Column4", type text}}),
    Custom1 = Table.FromList(Table.ColumnNames(#"Changed Type")),
    #"Merged Queries" = Table.NestedJoin(Custom1, {"Column1"}, TableB, {"Column Name"}, "TableB", JoinKind.LeftOuter),
    #"Expanded TableB" = Table.ExpandTableColumn(#"Merged Queries", "TableB", {"Extract Date"}, {"Extract Date"}),
    #"Added Custom" = Table.AddColumn(#"Expanded TableB", "Names", each [Column1] & " - " & [Extract Date]),
    Custom2 = Table.Group(#"Changed Type",{"Column1"},{{"Data",each _}}),
    #"Expanded Data" = Table.ExpandTableColumn(Custom2, "Data", {"Column1", "Column2", "Column3", "Column4"}, #"Added Custom"[Names]),
    #"Removed Columns" = Table.RemoveColumns(#"Expanded Data",{"Column1"})
in
    #"Removed Columns"

Best Regards,
Gao
Community Support Team

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