오늘은 RANK(), ROW_NUMBER() 비교하여 사용하여 보았다. --테이블 WITH CTE AS ( SELECT 'LEVEL1' AS A,'LEVEL11' AS B,'O' AS C UNION SELECT 'LEVEL1','LEVEL12','O' UNION SELECT 'LEVEL1','LEVEL13','O' UNION SELECT 'LEVEL1','LEVEL14','O' UNION SELECT 'LEVEL1','LEVEL15','A' UNION SELECT 'LEVEL1','LEVEL11','B' UNION SELECT 'LEVEL1','LEVEL11','C' UNION SELECT 'LEVEL1','LEVEL12','D' UNION SELECT 'LEVEL1','LEVEL13','E' UNION..