Query regarding merging

Hi, SushainKoul 

I assume that  it will change when the name length is less than 2.

Create a copy table, add a condition column to get the first name.

Now transform table with M code:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WCkrMSi3OUNJRCknNKk/MywSyPPNSMhOBdF5pTo5SrE60UjCQ4w3EwRmJRbkgGaeizJLEzDywpC9U0j0xLyUDpN0vtTwyvygbLOldlFmckQfS4l2am1iEYXgsAA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [FirstName = _t, LastName = _t, Country = _t, Col4 = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"FirstName", type text}, {"LastName", type text}, {"Country", type text}, {"Col4", type text}}),
    Custom1 = Table.ToRecords(#"Changed Type"),
    Custom2 = List.Transform(Custom1, each Record.ToList (_)),
    Custom3 = List.Transform(Custom2, each if Text.Length(_{1})<2 then List.Range(_,1,99) else _
),
    Custom4 = List.Zip(Custom3
),
    Custom5 = Table.FromColumns(Custom4
),
    #"Removed Columns1" = Table.RemoveColumns(Custom5,{"Column4"}),
    #"Added Index" = Table.AddIndexColumn(#"Removed Columns1", "Index", 0, 1, Int64.Type),
    #"Merged Queries" = Table.NestedJoin(#"Added Index", {"Index"}, _GetFirstName, {"Index"}, "Table (2)", JoinKind.LeftOuter),
    #"Expanded Table (2)" = Table.ExpandTableColumn(#"Merged Queries", "Table (2)", {"FirstName"}, {"FirstName"}),
    #"Reordered Columns" = Table.ReorderColumns(#"Expanded Table (2)",{"Column1", "FirstName", "Column2", "Column3", "Index"}),
    #"Removed Columns" = Table.RemoveColumns(#"Reordered Columns",{"Column1"})
in
    #"Removed Columns"

Result:

Finally, merge the two tables according to the Index column to get the first name

Please refer to the attachment below for details

Is this the result you want? Hope this is useful to you

Please feel free to let me know If you have further questions

Best Regards,
Community Support Team _ Zeon Zheng
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