Condition as if

See the working here - Open a blank query - Home - Advanced Editor - Remove everything from there and paste the below code to test (later on when you use the query on your dataset, you will have to change the source appropriately. If you have columns other than these, then delete Changed type step and do a Changed type for complete table from UI again)

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMlXSUTIyBgGlWB0MriGMa4Iqa4Iqa4oqa4bBjQUA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Column1 = _t, Column2 = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Column1", Int64.Type}, {"Column2", Int64.Type}}),
    #"Grouped Rows" = Table.Group(#"Changed Type", {"Column2"}, {{"Temp", each _, type table [Column1=nullable number, Column2=nullable number, Index=number]}}),
    #"Added Custom" = Table.AddColumn(#"Grouped Rows", "Custom", each let
DummyTbl = [Temp],
Result = Table.AddColumn(DummyTbl,"IF", each if List.AllTrue(List.Transform(DummyTbl[Column1],(x)=> x=DummyTbl[Column1]{0})) then "OK" else "NOK")
in
Result),
    #"Removed Columns" = Table.RemoveColumns(#"Added Custom",{"Column2", "Temp"}),
    #"Expanded Custom" = Table.ExpandTableColumn(#"Removed Columns", "Custom", {"Column1", "Column2", "IF"}, {"Column1", "Column2", "IF"})
in
    #"Expanded Custom"

Hi Anonymous ，

According to your description, here's my solution. Please paste the code in a blank query to see the applied steps.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMlXSUTIyBgGlWB0MriGMa4Iqa4Iqa4oqa4bBjQUA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Column1 = _t, Column2 = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Column1", Int64.Type}, {"Column2", Int64.Type}}),
    #"Grouped Rows" = Table.Group(#"Changed Type", {"Column2"}, {{"Count", each Table.RowCount(Table.Distinct(_)), Int64.Type}}),
    #"Added Custom" = Table.AddColumn(#"Grouped Rows", "IF", each if [Count]>1 then "nok" else "ok"),
    #"Merged Queries" = Table.NestedJoin(#"Changed Type", {"Column2"},#"Added Custom", {"Column2"},  "Added Custom", JoinKind.LeftOuter),
    #"Expanded Added Custom" = Table.ExpandTableColumn(#"Merged Queries", "Added Custom", {"IF"}, {"IF"})
in
    #"Expanded Added Custom"

Get the expected result.

Or a calculated column is easier.

Column =
IF (
    CALCULATE (
        DISTINCTCOUNT ( 'Table'[Column1] ),
        ALLEXCEPT ( 'Table', 'Table'[Column2] )
    ) > 1,
    "nok",
    "ok"
)

If you have other confusions, please feel free to let me know.

I attach my sample below for reference.

Best Regards,
Community Support Team _ kalyj

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