Mengambil 10 baris teratas dan menjumlahkan semua baris lainnya di baris 11

Anda tidak menentukan bagaimana Anda menentukan peringkat 10 besar, jadi saya berasumsi jumlah tertinggi berada di peringkat lebih tinggi?

With TopItems As
    (
    SELECT C.CountryID AS CountryID
            , C.CountryName AS Country
            , Count(FirstName) AS Origin
            , ROW_NUMBER() OVER( ORDER BY Count(FirstName) DESC ) As Num
    FROM Users AS U
        JOIN Country AS C 
            ON C.CountryID = U.CountryOfOrgin
    GROUP BY C.CountryName, C.CountryID
    )
Select CountryId, Country, Origin
From TopItems
Where Num <= 10
Union ALL
Select 0, 'Others', Sum(Origin)
From TopItems
Where Num > 10