Max date Keeping Ids Fixed

[Gcsingh149]

My first time with power query.

In power query I am trying to create a New column where it is only taking the max date per project ID i.e., keeping the Project ID fixed

ID	Date	Desired_Column
234561	Null	06/04/2023
234561	Null	06/04/2023
234561	Null	06/04/2023
234561	Null	06/04/2023
234561	Null	06/04/2023
234561	Null	06/04/2023
234561	Null	06/04/2023
234561	Null	06/04/2023
234561	Null	06/04/2023
234561	Null	06/04/2023
234561	Null	06/04/2023
234561	Null	06/04/2023
234561	Null	06/04/2023
234561	Null	06/04/2023
234561	08/03/2023	06/04/2023
234561	05/04/2023	06/04/2023
234561	06/04/2023	06/04/2023
234561	06/04/2023	06/04/2023
234561	06/04/2023	06/04/2023

[m_dekorte · Accepted solution]

Hi @Gcsingh149,

Give this a go.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjI2MTUzVNJRAiIDM10DE10jY6VYnVEJ6koYWOgaGINEcSowhYriVGBGEwWxAA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [ID = _t, Date = _t, Desired_Column = _t]),
    ChType = Table.TransformColumnTypes(Source,{{"Date", type date}, {"Desired_Column", type date}}),
    GroupRows = Table.Group(ChType, {"ID"}, {{"t", each List.Transform( [Date], (x)=> List.Max([Date])), type list}}),
    Expand = Table.ExpandListColumn(GroupRows, "t")
in
    Expand

with this result

I hope this is helpful

[Anonymous · Accepted solution]

Hi @Gcsingh149 ,

Please try.

List.Max( Table.SelectRows( PreviousStepName, (x) => x[ID] = [ID])[Date] )

all steps.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjI2MTUzVNJRUorVGfI8AwtdA2NdI2OEqBFI1FTXwART1Axd1JAI0VgA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [ID = _t, Date = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"ID", Int64.Type}, {"Date", type date}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type", "Max Date", each List.Max( Table.SelectRows( #"Changed Type", (x) => x[ID] = [ID])[Date] ))
in
    #"Added Custom"

Best Regards,
Gao
Community Support Team

If there is any post helps, then please consider Accept it as the solution  to help the other members find it more quickly. If I misunderstand your needs or you still have problems on it, please feel free to let us know. Thanks a lot!

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[m_dekorte · Accepted solution]

Hi @Gcsingh149,

Give this a go.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjI2MTUzVNJRAiIDM10DE10jY6VYnVEJ6koYWOgaGINEcSowhYriVGBGEwWxAA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [ID = _t, Date = _t, Desired_Column = _t]),
    ChType = Table.TransformColumnTypes(Source,{{"Date", type date}, {"Desired_Column", type date}}),
    GroupRows = Table.Group(ChType, {"ID"}, {{"t", each List.Transform( [Date], (x)=> List.Max([Date])), type list}}),
    Expand = Table.ExpandListColumn(GroupRows, "t")
in
    Expand

with this result

I hope this is helpful