SQL 등급 매기기

 

 

SELECT
	name,
	CASE
		WHEN absent >= 4 THEN 'F'
		WHEN score >= 90 THEN 'A'
		WHEN score >= 80 THEN 'B'
		WHEN score >= 70 THEN 'C'
		WHEN score >= 60 THEN 'D'
	ELSE 'F'
	END AS grade
FROM
	table
WHERE 
	name IS NOT NULL
	AND score IS NOT NULL
	AND absent IS NOT NULL

문제 풀이

   CASE WHEN THEN  / ELSE / END 을 사용해서 해결