CREATE FUNCTION [dbo].[fn_split]
(@arr nvarchar(4000), @sep nchar(1))
RETURNS table
AS
RETURN
  SELECT
    (n - 1) - LEN(REPLACE(LEFT(@arr, n-1), @sep, N'')) + 1 AS pos,
    SUBSTRING(@arr, n, CHARINDEX(@sep, @arr + @sep, n) - n) AS element
  FROM dbo.Nums
  WHERE n <= LEN(@arr) + 1
    AND SUBSTRING(@sep + @arr, n, 1) = @sep;
GO