Handling rows with multiple items

Hi, dongho 

Based on your description, I created data to reproduce your scenario. The pbix file is attached in the end.

Table:

You may try the following m codes in 'Advanced Editor'.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WyizJTTWMycssSc01UtJRKkvMKQXxwTRIILGkBMgFkkZKsTog5am5xhDlJjDlxlDlJhDlxmDlJkqxsQA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Column1 = _t, Column2 = _t, Column3 = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Column1", type text}, {"Column2", type text}, {"Column3", type text}}),
    Custom1 = Table.TransformColumns(#"Changed Type",{{"Column1",each Text.Split(_,"#(lf)")},{"Column2",each Text.Split(_,"#(lf)")},{"Column3",each Text.Split(_,"#(lf)")}}),
    #"Added Custom" = Table.AddColumn(Custom1, "Custom", each let x = List.Count([Column1]) in
List.Generate(
    ()=>0,
    each _<x,
    each _+1
)),
    #"Expanded Custom" = Table.ExpandListColumn(#"Added Custom", "Custom"),
    Custom2 = Table.TransformRows(#"Expanded Custom",each 
let c = [Custom] in
[Column1=_[Column1]{c},Column2=_[Column2]{c},Column3=_[Column3]{c}]),
    #"Converted to Table" = Table.FromList(Custom2, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
    #"Expanded Column1" = Table.ExpandRecordColumn(#"Converted to Table", "Column1", {"Column1", "Column2", "Column3"}, {"Column1.Column1", "Column1.Column2", "Column1.Column3"}),
    #"Renamed Columns" = Table.RenameColumns(#"Expanded Column1",{{"Column1.Column1", "Column1"}, {"Column1.Column2", "Column2"}, {"Column1.Column3", "Column3"}})
in
    #"Renamed Columns"

Result:

Best Regards

Allan

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