How to add serial number in Ms access query

I think very helpful demonstration for Access lover. Code Private lngRowNumber As Long Private colPrimaryKeys As VBA.Collection Public Function RowNumber(UniqueKeyVariant As Variant) As Long Dim lngTemp As Long On Error Resume Next lngTemp = colPrimaryKeys(CStr(UniqueKeyVariant)) If Err.Number Then lngRowNumber = lngRowNumber + 1 colPrimaryKeys.Add lngRowNumber, CStr(UniqueKeyVariant) lngTemp = lngRowNumber End If RowNumber = lngTemp End Function Public Function ResetRowNumber() As Boolean Set colPrimaryKeys = New VBA.Collection lngRowNumber = 0 ResetRowNumber = True End Function