Useful if there is a need to find gaps in SQL-Server table index.

FindMissingIndexes.sql

DECLARE @BrokenTable TABLE (ID INT NOT NULL);
INSERT INTO @BrokenTable VALUES (1);
INSERT INTO @BrokenTable VALUES (3);
INSERT INTO @BrokenTable VALUES (5);
INSERT INTO @BrokenTable VALUES (7);
INSERT INTO @BrokenTable VALUES (9);
WITH CTE
AS (SELECT 1 AS Number
	UNION ALL
	SELECT Number + 1
	FROM CTE
	WHERE Number <= 10)
SELECT TOP (5) *
FROM CTE
WHERE Number NOT IN (SELECT ID FROM @BrokenTable)
ORDER BY Number
OPTION (MAXRECURSION 0);