Problem with a relationship many to many

Hi lbarretta ,

Please try:

First, duplicate table1, then add a new column cost:

Expanded the cost column:

Then add a new column final cost:

Here is the M code:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMlTSUTLUMzBTitWJVjICcgz0DI3BHGMgx8RAz9IILgVRFwsA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Level = _t, factor = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Level", Int64.Type}, {"factor", type number}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type", "cost", each Table.SelectColumns(
Table.SelectRows(Table2, (x)=>x[Level]=[Level]),
"Cost")),
    #"Expanded cost" = Table.ExpandTableColumn(#"Added Custom", "cost", {"Cost"}, {"cost.Cost"}),
    #"Added Custom1" = Table.AddColumn(#"Expanded cost", "final cost", each [factor]*[cost.Cost])
in
    #"Added Custom1"

Final output:

Best Regards,

Jianbo Li

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