SQL to return the number of working days between 2 passed in dates

Question

I need to write an sql query that returns the number of Working days (Monday - Friday) between two given dates.

I was wondering what would be the most efficient way

Answer 1

This is how i do it, assuming you already got a calendar table with acolumn which indicates if a day is working day or not: Add a new column to your calendar table like workday_num and populate it once with a running number using

sum(case when workingday then 1 else 0 end)
over (order by calendardate rows unbounded preceding)

Now it's two joins to your calendar and a simple difference of the workday_nums of p_start_date and p_end_date.

Answer 2

Thats so simple :

    SQL> Select count(*)
      2  from ( select rownum rnum
      3          from all_objects
      4        where rownum <= to_date('18-dec-2009','dd-mon-yyyy') - 
    to_date('16-nov-2009')+1 )
      5    where to_char( to_date('16-nov-2009','dd-mon-yyyy')+rnum-1, 'DY' )
      6                not in ( 'SAT', 'SUN' )


      COUNT(*)
    ----------
            25

    SQL> Select to_char( to_date('16-nov-2009','dd-mon-yyyy')+rnum-1, 'DY dd-mon-yyyy' )
      2  from ( select rownum rnum
      3          from all_objects
      4        where rownum <= to_date('18-dec-2009','dd-mon-yyyy') - to_date('16-nov-2009')+1 )
      5    where to_char( to_date('16-nov-2009','dd-mon-yyyy')+rnum-1, 'DY' )
      6                not in ( 'SAT', 'SUN' )


DAY_DATE
---------------
MON 16-nov-2009
TUE 17-nov-2009
WED 18-nov-2009
THU 19-nov-2009
FRI 20-nov-2009
MON 23-nov-2009
TUE 24-nov-2009
WED 25-nov-2009
THU 26-nov-2009
FRI 27-nov-2009
MON 30-nov-2009
TUE 01-dec-2009
WED 02-dec-2009
THU 03-dec-2009
FRI 04-dec-2009
MON 07-dec-2009
TUE 08-dec-2009
WED 09-dec-2009
THU 10-dec-2009
FRI 11-dec-2009
MON 14-dec-2009
TUE 15-dec-2009
WED 16-dec-2009
THU 17-dec-2009
FRI 18-dec-2009

25 rows selected.

Answer 3

It can be achieved by:

select  SUM(decode ( to_CHAR((sysdate-ROWNUM),'DY'),'SUN',0,'SAT',0,1)) from all_objects where rownum < sysdate -  (sysdate -9) 

Answer 4

an easy way to calculate to number of weekdays between 2 dates is :

SELECT
date1,
date2,
((date2-date1)-2*FLOOR((date2-date1)/7)-DECODE(SIGN(TO_CHAR(date2,'D')-
    TO_CHAR(date1,'D')),-1,2,0)+DECODE(TO_CHAR(date1,'D'),7,1,0)-
    DECODE(TO_CHAR(date2,'D'),7,1,0))*24 as WorkDays
FROM
  tablename
ORDER BY date1,date2

Answer 5

Here is an example

with given_days(d) as(
  select <<start_date>> + level - 1
    from dual
  connect by level < = (<<end_date>> - <<start_date>>) + 1
)
select count(*)
  from given_days
where to_char(d, 'DY', 'NLS_DATE_LANGUAGE=english') not in ('SUN', 'SAT')

Demonstration

HR\XE> with given_days as(
  2    select (to_date('&&1', 'dd.mm.yyyy') + level - 1) as g_day
  3      from dual
  4    connect by level < = (to_date('&2', 'dd.mm.yyyy') - to_date('&&1', 'dd.mm.yyyy')) + 1
  5  )
  6  select count(g_day) as cnt
  7    from given_days
  8  where to_char(g_day, 'DY', 'NLS_DATE_LANGUAGE=english') not in ('SUN', 'SAT');
Enter value for 1: 10.10.2012
old   2:   select to_date('&&1', 'dd.mm.yyyy') + level - 1
new   2:   select to_date('10.10.2012', 'dd.mm.yyyy') + level - 1
Enter value for 2: 17.10.2012
old   4:   connect by level < = (to_date('&2', 'dd.mm.yyyy') - to_date('&&1', 'dd.mm.yyyy')) + 1
new   4:   connect by level < = (to_date('17.10.2012', 'dd.mm.yyyy') - to_date('10.10.2012', 'dd.mm.yyyy')) + 1

  cnt                                                                     
----------                           
   6                                                                      

Answer 6

Here you go...

1. First check how many days you got in the holiday table, excluding weekend days.

2. Get business days (MON to FRI) between the 2 dates and after that subtract the holiday days.

   create or replace
   FUNCTION calculate_business_days (p_start_date IN DATE, p_end_date IN DATE)
           RETURN NUMBER IS
           v_holidays     NUMBER;
           v_start_date   DATE   := TRUNC (p_start_date);
           v_end_date     DATE   := TRUNC (p_end_date);
           BEGIN
           IF v_end_date >= v_start_date
           THEN
                   SELECT COUNT (*)
                   INTO v_holidays
                   FROM holidays
                   WHERE day BETWEEN v_start_date AND v_end_date
                   AND day NOT IN (
                           SELECT hol.day 
                           FROM holidays hol 
                           WHERE MOD(TO_CHAR(hol.day, 'J'), 7) + 1 IN (6, 7)
                   );
   
           RETURN   GREATEST (NEXT_DAY (v_start_date, 'MON') - v_start_date - 2, 0)
                +   (  (  NEXT_DAY (v_end_date, 'MON')
                        - NEXT_DAY (v_start_date, 'MON')
                       )
                     / 7
                    )
                  * 5
                - GREATEST (NEXT_DAY (v_end_date, 'MON') - v_end_date - 3, 0)
                - v_holidays;
           ELSE
                   RETURN NULL;
           END IF;
   END calculate_business_days;
   

After that you can test it out, like:

    select 
            calculate_business_days('21-AUG-2013','28-AUG-2013') as business_days 
    from dual;