skip holiday & weekly off from two date - sql-server

Question

i am using sql server 2008 R2 , i am creating application leave form. when user apply leave i.e start date & end date then between two dates , all dates should skip if they fall in holiday & weekly off
CREATE TABLE #HolidayMaster
(
[HolidayID] [int] IDENTITY(1,1) NOT NULL,
[HolidayDescription] [nvarchar](50) NULL,
[HolidayDate] [date] NULL,
)
INSERT INTO #HolidayMaster
select 'New Year', '2016-01-01'
union
select 'National Developer Day', '2016-01-05'
CREATE TABLE #ShiftMaster
(
[ShiftID] [int] IDENTITY(1,1) NOT NULL,
[Sunday] [float] NULL,
[Monday] [float] NULL,
[Tuesday] [float] NULL,
[Wednesday] [float] NULL,
[Thursday] [float] NULL,
[Friday] [float] NULL,
[Saturday] [float] NULL
)
INSERT INTO #ShiftMaster
select 0,1,1,1,1,1,0
select *,DATENAME (dw,[HolidayDate]) as [DayName] from #HolidayMaster
select * from #ShiftMaster
drop table #HolidayMaster
drop table #ShiftMaster
Declare #LeaveStartDate date = '2013-01-01'
Declare #LeaveEndDate date = '2013-01-06'
--expected out put
DName Date Desc
Friday 2016-01-01 Holiday
Saturday 2016-01-02 WeeklyOff
Sunday 2016-01-03 WeeklyOff
Monday 2016-01-04 Working
Tuesday 2016-01-05 Holiday
Wednesday 2016-01-06 Working

Answer 1

You need a calendar table. I have used tally table to generate dates.
Declare #LeaveStartDate date = '2016-01-01'
Declare #LeaveEndDate date = '2016-01-06'
;WITH Nbrs_3( n ) AS ( SELECT 1 UNION SELECT 0 ),
Nbrs_2( n ) AS ( SELECT 1 FROM Nbrs_3 n1 CROSS JOIN Nbrs_3 n2 ),
Nbrs_1( n ) AS ( SELECT 1 FROM Nbrs_2 n1 CROSS JOIN Nbrs_2 n2 ),
Nbrs_0( n ) AS ( SELECT 1 FROM Nbrs_1 n1 CROSS JOIN Nbrs_1 n2 ),
Nbrs ( n ) AS ( SELECT 1 FROM Nbrs_0 n1 CROSS JOIN Nbrs_0 n2 ),
calendar(dates) as
(
SELECT Dateadd(dd, n - 1, #LeaveStartDate) AS Date
FROM (SELECT Row_number()OVER (ORDER BY n)
FROM Nbrs) D ( n )
WHERE n <= Datediff(day, #LeaveStartDate, #LeaveEndDate)+ 1
)
SELECT DName =d.day_name,
Date = c.dates,
CASE
WHEN HolidayDate IS NOT NULL THEN 'Holiday'
WHEN leav_iden = 0 THEN 'WeeklyOff'
WHEN HolidayDate IS NOT NULL
AND leav_iden = 0 THEN 'Holiday/WeeklyOff'
ELSE 'Working'
END AS [Desc]
FROM calendar c
JOIN (SELECT *
FROM #ShiftMaster
CROSS apply (VALUES ([Sunday],'Sunday'),
([Monday],'Monday'),
([Tuesday],'Tuesday'),
([Wednesday],'Wednesday'),
([Thursday],'Thursday'),
([Friday],'Friday'),
([Saturday],'Saturday') ) cs(leav_iden, day_name)) d
ON Datename(WEEKDAY, c.dates) = d.day_name
LEFT JOIN #HolidayMaster h
ON h.HolidayDate = c.dates
Result :
DName Date Desc
----- ---------- -------------
Sunday 2016-01-03 WeeklyOff
Monday 2016-01-04 Working
Tuesday 2016-01-05 Holiday
Wednesday 2016-01-06 Working
Friday 2016-01-01 Holiday
Saturday 2016-01-02 WeeklyOff

Answer 2

try
Declare #LeaveStartDate date = '2016-01-01'
Declare #LeaveEndDate date = '2016-01-06'
;with dts(dt) as (select #LeaveStartDate
union all
select dateadd(day,1,dt) from dts where dt<#LeaveEndDate),
shifmstr as (
select shiftID,'Sunday' as dname,[sunday] tp from #ShiftMaster union all
select shiftID,'Monday' ,Monday from #ShiftMaster union all
select shiftID,'Tuesday' ,Tuesday from #ShiftMaster union all
select shiftID,'Wednesday',Wednesday from #ShiftMaster union all
select shiftID,'Thursday',Thursday from #ShiftMaster union all
select shiftID,'Friday',Friday from #ShiftMaster union all
select shiftID,'Saturday',Saturday from #ShiftMaster)
select datename(dw,dt) DName,Dt,
case when c.HolidayDate is not null then 'Holiday'
when tp=1 then 'Working' else 'WeeklyOff' end descr
from dts a join shifmstr b on
datename(dw,a.dt)=b.dname left join
#HolidayMaster c on a.dt=c.HolidayDate

Answer 3

First thing you need is to generate the dates based on an interval. A nice an quick way is shown here. Then, you can LEFT JOIN with your #HolidayMaster table to check if a date is a holiday or not.
The code should look like this:
Declare #LeaveStartDate date = '2016-01-01'
Declare #LeaveEndDate date = '2016-01-06'
;WITH Dates_CTE AS (
SELECT TOP (DATEDIFF(DAY, #LeaveStartDate, #LeaveEndDate) + 1)
Date = DATEADD(DAY, ROW_NUMBER() OVER(ORDER BY a.object_id) - 1, #LeaveStartDate)
FROM sys.all_objects a
CROSS JOIN sys.all_objects b
)
SELECT DATENAME (dw,[Date]) as [DayName],
[Date],
(CASE WHEN DATEPART(dw, [Date]) IN (1, 7) THEN 'WeeklyOff'
WHEN HM.HolidayID IS NOT NULL THEN 'Holiday' -- HM.Description can be used here to actually display holiday name
ELSE 'Working' END) [Desc]
FROM Dates_CTE D
LEFT JOIN #HolidayMaster HM ON HM.HolidayDate = D.[Date]
Usually LEFT JOIN .. IS NULL check is slower than NOT EXISTS, so an an alternative is to remove LEFT JOIN and check for existence, but I find this form more readable.

Answer 4

Recursive CTE to generate dates between the date range, left join on HolidayMaster and left join on ShiftMaster (I changed the ShiftMaster to have day names to join on), then select the proper description depending on the values:
CREATE TABLE #HolidayMaster
(
[HolidayID] [int] IDENTITY(1,1) NOT NULL,
[HolidayDescription] [nvarchar](50) NULL,
[HolidayDate] [date] NULL,
)
INSERT INTO #HolidayMaster
select 'New Year', '2016-01-01'
union
select 'National Developer Day', '2016-01-05'
CREATE TABLE #ShiftMaster
(
[ShiftID] [int] IDENTITY(1,1) NOT NULL,
[Day] nvarchar(20) NULL,
IsHoliday bit NULL
)
INSERT INTO #ShiftMaster
values ('Sunday', 0), ('Monday', 1), ('Tuesday', 1), ('Wednesday',1), ('Thursday', 1), ('Friday', 1), ('Saturday',0)
select *,DATENAME (dw,[HolidayDate]) as [DayName] from #HolidayMaster
select * from #ShiftMaster
Declare #LeaveStartDate date = '2016-01-01'
Declare #LeaveEndDate date = '2016-01-06'
;WITH Dates AS (
SELECT
[Date] = #LeaveStartDate
UNION ALL SELECT
[Date] = DATEADD(DAY, 1, [Date])
FROM
Dates
WHERE
Date < #LeaveEndDate
) SELECT
DATENAME(dw, [Date])
, [Date]
, CASE WHEN hm.HolidayDescription IS NULL THEN
CASE WHEN sm.IsHoliday = 1 THEN 'Working' ELSE 'Weekly Off' END
ELSE 'Holiday' END AS Description
FROM
Dates
left join #HolidayMaster hm on hm.HolidayDate = [Date]
left join #ShiftMaster sm on sm.Day = DATENAME(dw, [Date])
drop table #HolidayMaster
drop table #ShiftMaster

Answer 5

try this,
DECLARE #LeaveStartDate DATETIME = '2016-01-01'
DECLARE #LeaveEndDate DATETIME = '2016-01-06'
;WITH CTE
AS ( SELECT #LeaveStartDate AS LeaveDate
UNION ALL
SELECT LeaveDate + 1
FROM CTE
WHERE LeaveDate < #LeaveEndDate
)
SELECT * ,DATENAME(WEEKDAY, c.LeaveDate)
FROM CTE c
LEFT JOIN #HolidayMaster h ON c.LeaveDate = h.HolidayDate
WHERE h.HolidayDate IS NULL
AND EXISTS ( SELECT 1
FROM #ShiftMaster s
WHERE (DATENAME(WEEKDAY, c.LeaveDate) = 'Sunday' AND s.Sunday = 1)
OR (DATENAME(WEEKDAY, c.LeaveDate) = 'Monday' AND s.Monday = 1)
OR (DATENAME(WEEKDAY, c.LeaveDate) = 'Tuesday' AND s.Tuesday = 1)
OR (DATENAME(WEEKDAY, c.LeaveDate) = 'Wednesday' AND s.Wednesday = 1)
OR (DATENAME(WEEKDAY, c.LeaveDate) = 'Thursday' AND s.Thursday = 1)
OR (DATENAME(WEEKDAY, c.LeaveDate) = 'Friday' AND s.Friday = 1)
OR (DATENAME(WEEKDAY, c.LeaveDate) = 'Saturday' AND s.Saturday = 1)
)
If you are looking to get all dates with status try this,
DECLARE #LeaveStartDate DATETIME = '2016-01-01'
DECLARE #LeaveEndDate DATETIME = '2016-01-06'
;WITH CTE
AS ( SELECT #LeaveStartDate AS LeaveDate
UNION ALL
SELECT LeaveDate + 1
FROM CTE
WHERE LeaveDate < #LeaveEndDate
)
SELECT
c.LeaveDate,
DATENAME(WEEKDAY, c.LeaveDate) AS [DayName],
CASE WHEN (DATENAME(WEEKDAY, c.LeaveDate) = 'Sunday' AND s.Sunday = 0)
OR (DATENAME(WEEKDAY, c.LeaveDate) = 'Monday' AND s.Monday = 0)
OR (DATENAME(WEEKDAY, c.LeaveDate) = 'Tuesday' AND s.Tuesday = 0)
OR (DATENAME(WEEKDAY, c.LeaveDate) = 'Wednesday' AND s.Wednesday = 0)
OR (DATENAME(WEEKDAY, c.LeaveDate) = 'Thursday' AND s.Thursday = 0)
OR (DATENAME(WEEKDAY, c.LeaveDate) = 'Friday' AND s.Friday = 0)
OR (DATENAME(WEEKDAY, c.LeaveDate) = 'Saturday' AND s.Saturday = 0)
THEN 'WeeklyOff'
WHEN h.HolidayDate IS NOT NULL
THEN 'Holiday'
ELSE 'Working'
END AS [Status]
FROM CTE c
CROSS JOIN #ShiftMaster s
LEFT JOIN #HolidayMaster h ON c.LeaveDate = h.HolidayDate