Database Challenges

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'

;
--This solution requires a Numbers table.
--Because I don't know if one is available, or if the user
--that executes this query has permissions to master..spt_values,
--one is being generated using cross joins and CTE's.
WITH Z AS (SELECT 1 AS N UNION ALL SELECT 1),
Y AS (SELECT A.N AS N FROM Z AS A CROSS JOIN Z AS B),
X AS (SELECT A.N AS N FROM Y AS A CROSS JOIN Y AS B),
Numbers AS (
	SELECT ROW_NUMBER() OVER(ORDER BY A.N) AS N
	FROM X AS A CROSS JOIN Y AS B
)

SELECT		Data, 
			[Char],
			MIN(Pos) AS Pos,
			COUNT(*) + 1  AS [Len]
FROM		(
				SELECT		T.Data, 
							SUBSTRING(T.Data, N.N, 1) AS [Char],
							N.N AS Pos,
							--It is necesary a reference column for the cases when 
							--a character forms different sequences in the same string.
							N.N - ROW_NUMBER() OVER(PARTITION BY DATA ORDER BY N.N) AS [Group]
				FROM		@t AS T
							INNER JOIN	Numbers AS N
										ON	N.N <= LEN(T.Data)
										--If the current char and the next are the same, then a sequence exists
										AND SUBSTRING(T.Data, N.N, 1) = SUBSTRING(T.Data, N.N+1, 1)
			) AS Seq
GROUP BY	Data, [Char], [Group]
ORDER BY	MAX(COUNT(*)) OVER(PARTITION BY Data) DESC,
			COUNT(COUNT(*)) OVER(PARTITION BY Data) DESC, Pos

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