Share 一个昨天写的函数。 目的是求给定的时间是所在月份的第几个礼拜。

DELIMITER $$USE `t_girl`$$DROP FUNCTION IF EXISTS `weekofmonth`$$CREATE DEFINER=`root`@`localhost` FUNCTION `weekofmonth`(    f_datetime DATETIME    ) RETURNS INT(11)BEGIN   -- Created by ytt.    DECLARE v_result INT;       DECLARE v_weekno INT;    SET v_weekno =    CASE DAYOFWEEK(f_datetime)    WHEN 1 THEN 7    WHEN 2 THEN 1    WHEN 3 THEN 2    WHEN 4 THEN 3    WHEN 5 THEN 4    WHEN 6 THEN 5    WHEN 7 THEN 6    END;    SET v_result = CEIL(DAYOFMONTH(DATE_SUB(f_datetime,INTERVAL v_weekno DAY))/7)+1;    RETURN v_result;    END$$DELIMITER ;

演示下结果：

SELECT weekofmonth(NOW()) AS result;

query result:

result

4