A.SELECT TIMESTAMPDIFF(YEAR,’2015-05-31’,now())AS ’年龄’B.SELECT DIFF(YEAR,’2015-05-31’,now())AS ’年龄’C.SELECT now()D.无法计算
A.等值连接B.非空连接C.相同连接D.空连接
A.DATE(birthday,’%m’)=DATE(now(),’%m’)B.DATE_FORMAT(birthday,’%m’)=DATE_FORMAT(now(),’%m’)C.DATE_FORMAT(now,’%M’)=DATE_FORMAT(birthday,’%M’)D.以上都不对