Sort two csv fields by removing duplicates and without row-by-row processing, Sql Server

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-- The DelimitedSplit8K is taken from Jeff Moden's Tally OH! An Improved SQL 8K “CSV Splitter” Function article at
-- http://www.sqlservercentral.com/articles/Tally+Table/72993/

CREATE FUNCTION [dbo].[DelimitedSplit8K]
--===== Define I/O parameters
        (@pString VARCHAR(8000), @pDelimiter CHAR(1))
--WARNING!!! DO NOT USE MAX DATA-TYPES HERE!  IT WILL KILL PERFORMANCE!
RETURNS TABLE WITH SCHEMABINDING AS
 RETURN
--===== "Inline" CTE Driven "Tally Table" produces values from 1 up to 10,000...
     -- enough to cover VARCHAR(8000)
  WITH E1(N) AS (
                 SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
                 SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
                 SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1
                ),                          --10E+1 or 10 rows
       E2(N) AS (SELECT 1 FROM E1 a, E1 b), --10E+2 or 100 rows
       E4(N) AS (SELECT 1 FROM E2 a, E2 b), --10E+4 or 10,000 rows max
 cteTally(N) AS (--==== This provides the "base" CTE and limits the number of rows right up front
                     -- for both a performance gain and prevention of accidental "overruns"
                 SELECT TOP (ISNULL(DATALENGTH(@pString),0)) ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) FROM E4
                ),
cteStart(N1) AS (--==== This returns N+1 (starting position of each "element" just once for each delimiter)
                 SELECT 1 UNION ALL
                 SELECT t.N+1 FROM cteTally t WHERE SUBSTRING(@pString,t.N,1) = @pDelimiter
                ),
cteLen(N1,L1) AS(--==== Return start and length (for use in substring)
                 SELECT s.N1,
                        ISNULL(NULLIF(CHARINDEX(@pDelimiter,@pString,s.N1),0)-s.N1,8000)
                   FROM cteStart s
                )
--===== Do the actual split. The ISNULL/NULLIF combo handles the length for the final element when no delimiter is found.
 SELECT ItemNumber = ROW_NUMBER() OVER(ORDER BY l.N1),
        Item       = SUBSTRING(@pString, l.N1, l.L1)
   FROM cteLen l
;
GO

CREATE TABLE csv_test
    (
        Col1 VARCHAR(100),
        Col2 VARCHAR(100),
        Col3 VARCHAR(500)
    );

INSERT dbo.csv_test (Col1, Col2)
VALUES ('xyz,def,abc', 'abc*,tuv,def,xyz*,abc'), ('qwe,bca,a23', 'qwe,bca,a23*,abc')

;WITH cte1 as
    (
        SELECT  Col1, 
                Col2, 
                Col3,
                ROW_NUMBER() OVER(ORDER BY Col1, Col2) As rn
        FROM dbo.csv_test
    ), cte2 as
    (
        SELECT rn, Item
        FROM cte1
        CROSS APPLY 
        (
            SELECT DISTINCT Item 
            FROM dbo.DelimitedSplit8K(Col1 +','+ Col2, ',') 
        ) x
    ), cte3 AS
    (
        SELECT rn, Item
        FROM cte2 t0
        WHERE NOT EXISTS
        (
            SELECT 1
            FROM cte2 t1
            WHERE t0.Item + '*' = t1.Item
            AND t0.rn = t1.rn
        )
    ), cte4 AS
    (
        SELECT rn, 
               STUFF
               ((
                 SELECT  ',' + Item
                 FROM cte3 t1
                 WHERE t1.rn = t0.rn
                 ORDER BY Item
                 FOR XML PATH('')
               ), 1, 1, '') Combined_Unique_Sorted
        FROM cte3 t0
    )

UPDATE t0
    SET Col3 = Combined_Unique_Sorted
    FROM cte1 t0
    INNER JOIN cte4 t1 ON t0.rn = t1.rn

SELECT *
    FROM csv_test
    ORDER BY Col1, Col2

View schema
Execution time: 0,09 sec, rows selected: 2, rows affected: 4, absolute service time: 0,22 sec

Sort two csv fields by removing duplicates and without row-by-row proc...