Database Challenges

;WITH Nbrs As (
	SELECT	Number n 
	FROM	master..spt_values spt 
	WHERE	spt.Type='P' And spt.Number Between 1 And 36
)
, x As (
	SELECT	t.Data
			, Left(Substring(t.Data, n1.n, n2.n), 1) c
			, n1.n p
			, Len(Substring(t.Data, n1.n, n2.n)) l
	FROM	Nbrs n1
			CROSS JOIN Nbrs n2
			CROSS JOIN @t t
	WHERE	n2.n >1 and n1.n + n2.n <= charindex('-','AAAAAAAA-AAAA-AAAA-AAAA-AAAAAAAAAAAA-', n1.n)
			And Replace(Substring(t.Data, n1.n, n2.n), Left(Substring(t.Data, n1.n, n2.n), 1), '') = ''
			And Left(Substring(t.Data, n1.n, n2.n), 1) != Substring(t.Data, n1.n + n2.n, 1)
			And Left(Substring(t.Data, n1.n, n2.n), 1) != Substring(t.Data, n1.n - 1, 1)
)
, o As (
	SELECT	x.Data, Max(x.l) ml, count(*) ng
	FROM	x
	GROUP BY x.Data
)
SELECT	x.Data, x.c [Char], x.p Pos, x.l [Len]
FROM	x
		INNER JOIN o ON o.Data = x.Data
ORDER BY o.ml DESC, o.ng DESC, x.p;

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