Database Challenges

--Eric_Freeman_tsqlchallenge_20_v1.sql
;WITH FiboNumbers(PreviousNumber, FiboNumber, NumRepeats) AS (
	SELECT CAST(0 AS BIGINT), CAST(1 AS BIGINT), CAST(0 AS INT)
	UNION ALL
    SELECT FiboNumber, PreviousNumber + FiboNumber
		, CASE CHARINDEX('00', CAST((PreviousNumber + FiboNumber) AS VARCHAR(19))) WHEN 0 THEN 0 ELSE 1 END
		+ CASE CHARINDEX('11', CAST((PreviousNumber + FiboNumber) AS VARCHAR(19))) WHEN 0 THEN 0 ELSE 1 END
		+ CASE CHARINDEX('22', CAST((PreviousNumber + FiboNumber) AS VARCHAR(19))) WHEN 0 THEN 0 ELSE 1 END
		+ CASE CHARINDEX('33', CAST((PreviousNumber + FiboNumber) AS VARCHAR(19))) WHEN 0 THEN 0 ELSE 1 END
		+ CASE CHARINDEX('44', CAST((PreviousNumber + FiboNumber) AS VARCHAR(19))) WHEN 0 THEN 0 ELSE 1 END
		+ CASE CHARINDEX('55', CAST((PreviousNumber + FiboNumber) AS VARCHAR(19))) WHEN 0 THEN 0 ELSE 1 END
		+ CASE CHARINDEX('66', CAST((PreviousNumber + FiboNumber) AS VARCHAR(19))) WHEN 0 THEN 0 ELSE 1 END
		+ CASE CHARINDEX('77', CAST((PreviousNumber + FiboNumber) AS VARCHAR(19))) WHEN 0 THEN 0 ELSE 1 END
		+ CASE CHARINDEX('88', CAST((PreviousNumber + FiboNumber) AS VARCHAR(19))) WHEN 0 THEN 0 ELSE 1 END
		+ CASE CHARINDEX('99', CAST((PreviousNumber + FiboNumber) AS VARCHAR(19))) WHEN 0 THEN 0 ELSE 1 END
    FROM FiboNumbers
    WHERE PreviousNumber <= 4611686018427387904) --half of bigint max value
, FiboNumbersByNumRepeats AS (
	SELECT ROW_NUMBER() OVER (PARTITION BY NumRepeats ORDER BY FiboNumber) AS TopX
		, FiboNumber
		, NumRepeats
	FROM FiboNumbers
	where NumRepeats > 0)
--PRESENTATION
SELECT NumRepeats, FiboNumber
FROM FiboNumbersByNumRepeats
WHERE TopX <= 5

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