How to convert Table/list into comma separated string

Hi Metran 

You can put the following code to advanced editor in power query

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMlSK1YlWMgKTxmDSBEyagkkzMGkOJi3ApKVSbCwA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [ID = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"ID", type text}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type", "Custom", each Text.Combine(#"Changed Type"[ID],","))
in
    #"Added Custom"

Output

Best Regards!

Yolo Zhu

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