A.SELECT 姓名,性别,YEAR(DATE())-YEAR(出生日期) 年龄 FROM 职工 WHERE 年龄<=40
B.SELECT 姓名,性别,YEAR(DATE())-YEAR(出生日期) 年龄 FROM 职工 WHERE YEAR(出生日期)<=40
C.SELECT 姓名,性别,YEAR(DATE())-YEAR(出生日期) 年龄 FROM 职工 WHERE YEAR(DATE())-YEAR(出生日期)<=40
D.SELECT 姓名,性别,年龄=YEAR(DATE())-YEAR(出生日期) FROM 职工 WHERE YEAR(DATE())-YEAR(出生日期)<=40