How to find closest date after certain date in Power Query? (Example shown)

Hi whatisdata96 ,

You should at least add a custom column.

if [Type]="I" then List.Min(Table.SelectRows(#"Changed Type", (x)=>x[Number]=[Number] and x[Type]="O"and x[Date]>[Date])[Date]) else ""

Result:

Here's the whole M syntax:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjQyNlHSUfIEYiN9QwN9IwMjI6VYHRQJQ9wSpjjEzRDipmbmFnBxI2PSJEz0jUwxJPwhOjDthkiY4xA3xK7BCEUCyQpTuC9iAQ==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Number = _t, Type = _t, Date = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Number", Int64.Type}, {"Type", type text}, {"Date", type date}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type", "Custom", each if [Type]="I" then List.Min(Table.SelectRows(#"Changed Type", (x)=>x[Number]=[Number] and x[Type]="O"and x[Date]>[Date])[Date]) else "")
in
    #"Added Custom"

I attach my sample below for your reference.

Best Regards,
Community Support Team _ kalyj

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