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' 

;WITH cte AS
(
	SELECT	data
	,		1 AS pos
	,		left(data, 1) AS chr
	,		1 AS length
	,		1 AS grp
	,		1 AS start_pos 
	FROM	@t 

	UNION ALL

	SELECT  c.data
	,		c.pos + 1
	, 		SUBSTRING(c.data, c.pos+1, 1)
	, 		CASE 
				WHEN SUBSTRING(t.data, c.pos+1, 1) = c.chr THEN c.length + 1
				ELSE 1 
			END
	,		CASE 
				WHEN SUBSTRING(t.data, c.pos+1, 1) = c.chr THEN c.grp
				ELSE c.grp + 1
			END
	,		CASE 
				WHEN SUBSTRING(t.data, c.pos+1, 1) = c.chr THEN c.start_pos
				ELSE c.pos+1
			END 
	FROM	@t t
	JOIN	cte c
	ON		t.data = c.data
	WHERE	c.pos < LEN(c.data)
)
,
result AS
(
	SELECT		data
	,			chr [Char]
	,			start_pos AS Pos
	,			MAX(length)[Len]
	FROM		cte
	WHERE		length > 1
	GROUP BY	data
	,			chr
	,			grp
	,			start_pos
)
SELECT	Data
,		[Char]
,		Pos
,		[Len] 
FROM	result
ORDER BY	MAX([len]) OVER(PARTITION BY data) DESC
,			data
,			pos

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