SELECT DAYOFWEEK(NOW()),WEEKDAY(now()),DATE_FORMAT(NOW(),"%w"),NOW()
now()是星期2
從上面結果來看。
DATE_FORMAT(NOW(),"%w") 2 正好對應
DAYOFWEEK(NOW())  3 大了
WEEKDAY(now()) 1 小了
 （可以理解為DAYOFWEEK長度大于WEEKDAY所以DAYOFWEEK得到為3，WEEKDAY得到為1）