Database Challenges

/* Test data */

DECLARE @t TABLE (Data VARCHAR(40)) 
 
INSERT @t (Data) SELECT '9992EDC6-D117-4DEE-B410-4E5FAE46AE97' 
INSERT @t (Data) SELECT '0BFC936B-BD9A-4C6A-AFB2-CF3F1752F8B1' 
INSERT @t (Data) SELECT '4A73E7EB-7777-4A04-9258-F1E75097977C' 
INSERT @t (Data) SELECT '5AAF477C-274D-400D-9067-035968F33B19' 
INSERT @t (Data) SELECT '725DA718-30D0-44A9-B36A-89F27CDFEEDE' 
INSERT @t (Data) SELECT '8083ED5A-D3B9-4694-BB04-F0B09C588888' 
 
SELECT * FROM @t

/* Solution follows */

;WITH cteChar(data, pos, ch, seq) AS (
	SELECT T.Data, N.number,
		SUBSTRING(T.Data, N.number, 1),
		ROW_NUMBER() OVER (PARTITION BY T.Data, SUBSTRING(T.Data, N.number, 1) ORDER BY N.number)
	FROM @t T
		CROSS JOIN (
			SELECT 1 AS number UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9 UNION ALL SELECT 10 
			UNION ALL SELECT 11 UNION ALL SELECT 12 UNION ALL SELECT 13 UNION ALL SELECT 14 UNION ALL SELECT 15 UNION ALL SELECT 16 UNION ALL SELECT 17 UNION ALL SELECT 18 UNION ALL SELECT 19 UNION ALL SELECT 20 
			UNION ALL SELECT 21 UNION ALL SELECT 22 UNION ALL SELECT 23 UNION ALL SELECT 24 UNION ALL SELECT 25 UNION ALL SELECT 26 UNION ALL SELECT 27 UNION ALL SELECT 28 UNION ALL SELECT 29 UNION ALL SELECT 30 
			UNION ALL SELECT 31 UNION ALL SELECT 32 UNION ALL SELECT 33 UNION ALL SELECT 34 UNION ALL SELECT 35 UNION ALL SELECT 36
		) N
), cteSeq(data, ch, pos, length) AS (
	SELECT data, ch, MIN(pos), COUNT(*)
	FROM cteChar
	GROUP BY data, ch, pos - seq
	HAVING COUNT(*) > 1
), cteAgg(data, gn, rn) AS (
	SELECT data,
		ROW_NUMBER() OVER (PARTITION BY data ORDER BY length DESC, COUNT(*) DESC),
		ROW_NUMBER() OVER (ORDER BY length DESC, COUNT(*) DESC)
	FROM cteSeq
	GROUP BY data, length
)
SELECT S.data AS [Data], S.ch AS [Char], S.pos AS [Pos], S.length AS [Len]
FROM cteSeq S 
	INNER JOIN cteAgg A ON (S.data = A.data AND A.gn = 1)
ORDER BY A.rn, S.pos

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