PowerQuery - max date by product

[mb0307]

Hi,

I need help with PowerQuery - thanks in advance.

I have a table below:

I need to create a Custom Column in PowerQuery showing Max Date per Product.  

Result in same table:

Thanks.

[mb0307]

@Anonymous  thanks.  

[Anonymous · Accepted solution]

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[Vera_33]

Hi @mb0307 

Have a try

let
  Source = Table.FromRows(
    Json.Document(
      Binary.Decompress(
        Binary.FromText(
          "i45WMlTSUTIw1Dew1DcyMDJUitWBChlhChljCpmgCBkBhQwN9YEIVcgIU8gYU8gEIRQLAA==",
          BinaryEncoding.Base64
        ),
        Compression.Deflate
      )
    ),
    let
      _t = ((type nullable text) meta [Serialized.Text = true])
    in
      type table [Product = _t, Date = _t]
  ),
  #"Changed Type" = Table.TransformColumnTypes(
    Source,
    {{"Product", Int64.Type}, {"Date", type date}}
  ),
  #"Grouped Rows" = Table.Group(
    #"Changed Type",
    {"Product"},
    {{"Max", each List.Max([Date]), type nullable date}}
  ),
  #"Merged Queries" = Table.NestedJoin(
    #"Changed Type",
    {"Product"},
    #"Grouped Rows",
    {"Product"},
    "Grouped Rows",
    JoinKind.LeftOuter
  ),
  #"Expanded Grouped Rows" = Table.ExpandTableColumn(
    #"Merged Queries",
    "Grouped Rows",
    {"Max"},
    {"Max"}
  )
in
  #"Expanded Grouped Rows"

[mb0307]

@Vera_33 

Thanks for your response but I am struggling to execute the query due to my limited knowledge.  Sorry about that.

I have updated the original post - basically I want result in same table.  Is it possible to do in Custom Column window?

Thanks.