How to exclude holidays between two dates? - oracle

Question

I have two dates and I have to find out the number of Sundays and holidays fall between those two dates. Can I do this using BETWEEN? If so, how?
SELECT date1, date2, trunc(deposit_date - transaction_date) TOTAL
FROM Table_Name FULL OUTER JOIN Holidays ON date2 = hdate
WHERE hdate IN (date1, date2)
Using this I can definitely check whether there is a holiday on either of the two days, i.e. date1 or date2 but what I am not able to find out that whether there lies a holiday or a Sunday between these two dates. Help!

Answer 1

The solution you've posted is horribly inefficient; you can do all of this in a single SQL statement:
Firstly generate all possible dates between the two you have:
select trunc(:min_date) + level - 1
from dual
connect by level <= trunc(:min_date) - trunc(:max_date)
Then use your HOLIDAY table to restrict to what you want:
with all_dates as (
select trunc(:min_date) + level - 1 as the_date
from dual
connect by level <= trunc(:min_date) - trunc(:max_date)
)
select count(*)
from all_dates a
left outer join holiday b
on a.the_date = b.hdate
where b.hdate is null
and to_char(a.the_date, 'DY') <> 'SUN'

Answer 2

If you want to check if hdate is between the two dates you can query using
where hdate between date1 and date2
If you want to check if hdate is on the same day as date1 or date two you can query like this
where trunc(hdate) in (trunc(date1) ,trunc(date2))
The trunc function removed the time.

Answer 3

You should create a table with the holidays and maintain it on your own.
CREATE TABLE holidays
(
holiday VARCHAR2(100)
, d_date DATE
);
INSERT INTO holidays VALUES ('National Developer Day', DATE'2013-06-01');
SELECT *
FROM holidays;
-- National Developer Day 2013-06-01 00:00:00
The rest is just a matter of a SQL statment
Scenario 1: EXISTS
SELECT COUNT
(
CASE
WHEN TRIM(TO_CHAR(d.start_date_level, 'DAY')) = 'SUNDAY'
OR CASE
WHEN EXISTS (SELECT 1 FROM holidays h WHERE d.start_date_level = h.d_date)
THEN 1
ELSE NULL
END = 1
THEN 1
ELSE NULL
END
) AS holiday_check
FROM
(
SELECT start_date + (LEVEL - 1) AS start_date_level
FROM
(
SELECT start_date, end_date, end_date - start_date AS diff_date
FROM
(
SELECT TRUNC(ADD_MONTHS(SYSDATE, -2)) AS start_date
, TRUNC(SYSDATE) AS end_date
FROM DUAL
)
)
CONNECT BY
LEVEL <= (diff_date + 1)
) d
Scenario 2: LEFT JOIN
SELECT COUNT
(
CASE
WHEN TRIM(TO_CHAR(d.start_date_level, 'DAY')) = 'SUNDAY'
OR h.d_date IS NOT NULL
THEN 1
ELSE NULL
END
) AS holiday_check
FROM
(
SELECT start_date + (LEVEL - 1) AS start_date_level
FROM
(
SELECT start_date, end_date, end_date - start_date AS diff_date
FROM
(
SELECT TRUNC(ADD_MONTHS(SYSDATE, -2)) AS start_date
, TRUNC(SYSDATE) AS end_date
FROM DUAL
)
)
CONNECT BY
LEVEL <= (diff_date + 1)
) d
LEFT JOIN holidays h
ON d.start_date_level = h.d_date
9 Sundays + 1 "National Developer Day" = 10

Answer 4

CREATE OR REPLACE FUNCTION workdays (dt1 DATE, dt2 DATE) RETURN NUMBER IS
weekday_count NUMBER := 0;
date1 DATE := dt1;
date2 DATE := dt2;
cur_dt date;
holiday_count number;
begin
if date1 = date2 then
return 0;
end if;
cur_dt := transaction_date;
while cur_dt <= date2 loop
if cur_dt = date2 then
null;
else
SELECT count(*) INTO holiday_count
FROM holiday
WHERE hdate = cur_dt;
IF holiday_count = 0 THEN
IF to_char(cur_dt,'DY') NOT IN ('SUN') THEN
weekday_count := weekday_count + 1;
END IF;
END IF;
END IF;
cur_dt := cur_dt +1;
END LOOP;
RETURN weekday_count;
END;
And then I queried my database and got the right results. Do post if you have an optimal solution for this.

Answer 5

Here is an even better and efficient solution to the problem,
SELECT A.ID,
COUNT(A.ID) AS COUNTED
FROM tableA A
LEFT JOIN TableB B
ON A.tableB_id=B.id
LEFT JOIN holiday C
ON TRUNC(C.hdate) BETWEEN (TRUNC(a.date1) +1) AND TRUNC(B.date2)
WHERE c.hdate IS NOT NULL
GROUP BY A.ID;
where TableA contains date1 and tableB contains date2. Holiday contains the list of holidays and Sundays. And this query excludes 'date1' from the count.
RESULT LOGIC
trunc(date2) - trunc(date1) = x
x - result of the query

Answer 6

Make a table T$HOLIDAYS with your holidays (HDATE column). These dates will be excluded from calculation of working days within given period (sdate is start date and edate end date of period). Here is the function that calculates working days within given period excluding holidays, saturdays and sundays:
CREATE OR REPLACE FUNCTION WorkingDays(sdate IN DATE,edate IN DATE) RETURN NUMBER IS
days NUMBER;
BEGIN
WITH dates AS (SELECT sdate+LEVEL-1 AS d FROM DUAL CONNECT BY LEVEL<=edate-sdate+1)
SELECT COUNT(*) INTO days
FROM dates
WHERE d NOT IN (SELECT hdate FROM t$holidays) --exclude holidays
AND TO_CHAR(d,'D') NOT IN (6,7); --exclude saturdays + sundays
RETURN days;
END WorkingDays;
/

Answer 7

select sum(qq) from (
select case when to_number(to_char((trunc(sysdate-10) + level - 1),'D'))<=5 then 1 else 0 end as qq
from dual
connect by level <= trunc(sysdate) - trunc(sysdate-10))