计算两个日期之间的天数，不包括周末(仅限MySQL)

Question

我需要计算MySQL中不包括周末(星期六和星期日)的两个日期之间的差异(以天为单位)。也就是说，天数减去周六和周日之间的天数。

目前，我只是简单地使用以下命令来计算时间：

SELECT DATEDIFF('2012-03-18', '2012-03-01')

返回17，但是我想排除周末，所以我想要12 (因为第3天和第4天、第10天、第11天和第17天是周末)。

我不知道从何说起。我知道WEEKDAY()函数和所有相关的函数，但我不知道如何在此上下文中使用它们。

Answer 1

插图：

mtwtfSSmtwtfSS
  123456712345   one week plus 5 days, you can remove whole weeks safely
  12345-------   you can analyze partial week's days at start date
  -------12345   or at ( end date - partial days )

伪码：

@S          = start date
@E          = end date, not inclusive
@full_weeks = floor( ( @E-@S ) / 7)
@days       = (@E-@S) - @full_weeks*7   OR (@E-@S) % 7

SELECT
  @full_weeks*5 -- not saturday+sunday
 +IF( @days >= 1 AND weekday( S+0 )<=4, 1, 0 )
 +IF( @days >= 2 AND weekday( S+1 )<=4, 1, 0 )
 +IF( @days >= 3 AND weekday( S+2 )<=4, 1, 0 )
 +IF( @days >= 4 AND weekday( S+3 )<=4, 1, 0 )
 +IF( @days >= 5 AND weekday( S+4 )<=4, 1, 0 )
 +IF( @days >= 6 AND weekday( S+5 )<=4, 1, 0 )
 -- days always less than 7 days

Answer 2

只需使用一个简单的函数进行尝试：

CREATE FUNCTION TOTAL_WEEKDAYS(date1 DATE, date2 DATE)
RETURNS INT
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);

测试：

SELECT TOTAL_WEEKDAYS('2013-08-03', '2013-08-21') weekdays1,
       TOTAL_WEEKDAYS('2013-08-21', '2013-08-03') weekdays2;

结果：

| WEEKDAYS1 | WEEKDAYS2 |
-------------------------
|        13 |        13 |

Answer 3

Below function will give you the Weekdays, Weekends, Date difference with proper results:

You can call the below function like,
select getWorkingday('2014-04-01','2014-05-05','day_diffs');
select getWorkingday('2014-04-01','2014-05-05','work_days');
select getWorkingday('2014-04-01','2014-05-05','weekend_days');




    DROP FUNCTION IF EXISTS PREPROCESSOR.getWorkingday;
    CREATE FUNCTION PREPROCESSOR.`getWorkingday`(d1 datetime,d2 datetime, retType varchar(20)) RETURNS varchar(255) CHARSET utf8
    BEGIN
     DECLARE dow1, dow2,daydiff,workdays, weekenddays, retdays,hourdiff INT;
        declare newstrt_dt datetime;
       SELECT dd.iDiff, dd.iDiff - dd.iWeekEndDays AS iWorkDays, dd.iWeekEndDays into daydiff, workdays, weekenddays
      FROM (
       SELECT
         dd.iDiff,
         ((dd.iWeeks * 2) + 
          IF(dd.iSatDiff >= 0 AND dd.iSatDiff < dd.iDays, 1, 0) + 
          IF (dd.iSunDiff >= 0 AND dd.iSunDiff < dd.iDays, 1, 0)) AS iWeekEndDays
           FROM (
          SELECT  dd.iDiff, FLOOR(dd.iDiff / 7) AS iWeeks, dd.iDiff % 7 iDays, 5 - dd.iStartDay AS iSatDiff,  6 - dd.iStartDay AS iSunDiff
         FROM (
          SELECT
            1 + DATEDIFF(d2, d1) AS iDiff,
            WEEKDAY(d1) AS iStartDay
          ) AS dd
        ) AS dd
      ) AS dd ;
      if(retType = 'day_diffs') then
      set retdays = daydiff; 
     elseif(retType = 'work_days') then
      set retdays = workdays; 
     elseif(retType = 'weekend_days') then  
      set retdays = weekenddays; 
     end if; 
        RETURN retdays; 
        END;


Thank You.
Vinod Cyriac.
Bangalore