====== Count weekdays between two dates in MySql ======
<code sql>
DELIMITER $$

CREATE DEFINER=`su`@`%` FUNCTION `TOTAL_WEEKDAYS`(date1 DATE, date2 DATE) RETURNS INT(11)
RETURN ABS(DATEDIFF(date2, date1)) + 1
     - ABS(DATEDIFF(ADDDATE(date2, INTERVAL 1 - DAYOFWEEK(date2) DAY),
                    ADDDATE(date1, INTERVAL 1 - DAYOFWEEK(date1) DAY))) / 7 * 2
     - (DAYOFWEEK(IF(date1 < date2, date1, date2)) = 1)
     - (DAYOFWEEK(IF(date1 > date2, date1, date2)) = 7)$$

DELIMITER ;
</code>