Using T-SQL, return nth delimited element from a string

Question

I have a need to create a function the will return nth element of a delimited string.

For a data migration project, I am converting JSON audit records stored in a S

Answer 1

Here is my initial solution... It is based on work by Aaron Bertrand http://www.sqlperformance.com/2012/07/t-sql-queries/split-strings

I simply changed the return type to make it a scalar function.

Example: SELECT dbo.GetSplitString_CTE('1,222,2,67,888,1111',',',4)

CREATE FUNCTION dbo.GetSplitString_CTE
(
   @List       VARCHAR(MAX),
   @Delimiter  VARCHAR(255),
   @ElementNumber int
)
RETURNS VARCHAR(4000)
AS
BEGIN

   DECLARE @result varchar(4000)    
   DECLARE @Items TABLE ( position int IDENTITY PRIMARY KEY,
                          Item VARCHAR(4000)
                         )  

   DECLARE @ll INT = LEN(@List) + 1, @ld INT = LEN(@Delimiter);  

   WITH a AS
   (
       SELECT
           [start] = 1,
           [end]   = COALESCE(NULLIF(CHARINDEX(@Delimiter, 
                       @List, @ld), 0), @ll),
           [value] = SUBSTRING(@List, 1, 
                     COALESCE(NULLIF(CHARINDEX(@Delimiter, 
                       @List, @ld), 0), @ll) - 1)
       UNION ALL
       SELECT
           [start] = CONVERT(INT, [end]) + @ld,
           [end]   = COALESCE(NULLIF(CHARINDEX(@Delimiter, 
                       @List, [end] + @ld), 0), @ll),
           [value] = SUBSTRING(@List, [end] + @ld, 
                     COALESCE(NULLIF(CHARINDEX(@Delimiter, 
                       @List, [end] + @ld), 0), @ll)-[end]-@ld)
       FROM a
       WHERE [end] < @ll
   )
   INSERT @Items SELECT [value]
   FROM a
   WHERE LEN([value]) > 0
   OPTION (MAXRECURSION 0);

   SELECT @result=Item
   FROM @Items
   WHERE position=@ElementNumber

   RETURN @result;
END
GO