版权声明:严禁转载 https://blog.csdn.net/qq_38452951/article/details/83793873
SELECT CASE
WHEN grade >= 90 THEN '优秀'
WHEN grade >= 80 THEN '良好'
WHEN grade >= 70 THEN '中等'
WHEN grade >= 60 THEN '及格'
ELSE '不及格'
END
AS '成绩'
from SC