Starting result set at certain point in results - sql

Question

I've got an issue I'm a little stuck with. Basically, I have a table with 4 columns, one column is a date and the results returned are dependent on time of day. If the time is before 6pm return the data as is but if after 6, find the next available day.
This is some sample data assuming today is 2014-07-10:
+----------+---------------------+-----------------+----------------+
| Workzone | ScheduleDate | NextDayDelivery | StdDayDelivery |
+----------+---------------------+-----------------+----------------+
| SWANS | 2014-07-11 00:00:00 | 1 | 1 |
| SWANS | 2014-07-12 00:00:00 | 0 | 1 |
| SWANS | 2014-07-13 00:00:00 | 0 | 0 |
| SWANS | 2014-07-14 00:00:00 | 0 | 1 |
| SWANS | 2014-07-15 00:00:00 | 0 | 1 |
| SWANS | 2014-07-16 00:00:00 | 0 | 1 |
| SWANS | 2014-07-17 00:00:00 | 0 | 1 |
| SWANS | 2014-07-18 00:00:00 | 0 | 1 |
| SWANS | 2014-07-19 00:00:00 | 0 | 1 |
| SWANS | 2014-07-20 00:00:00 | 0 | 0 |
+----------+---------------------+-----------------+----------------+
This is the query so far:
DECLARE #hour AS Int
SET #hour = DatePart(hour, getdate())
SET #hour = 19
-- Work out if the time is before 18:00. If it is then this is the easy bit, use the data as is.
IF (#hour <= 18)
BEGIN
SELECT
[Workzone]
,[ScheduleDate]
,[NextDayDelivery]
,[StdDayDelivery]
FROM [tbl_Sys_QuickstartDeliveryQuota]
END
ELSE
BEGIN
-- OTHER QUERY HERE --
END
So the above simply checks the hour and performs a query based on that. If before 6pm then simply view the data in the table as it is otherwise execute the other query which is what i'm stuck on.
The sample data above is generated for the next day onwards so if today is the 2014-07-10 then the data will start from the 2014-07-11. The NextDayDelivery column will always start with 1 if the following day is a weekday or saturday with all following days set to 0 and the StdDayDelivery column will have 1 if on a weekday or saturday or 0 if a sunday or bank holiday.
What I need to do is adjust the results if the time is after 6 as this will change the next day delivery.
My thoughts are to use the StdDayDelivery column to work out the next available delivery day so then in the sample data provided the 2014-07-12 will become the first row (if today is the 11th) of the results with NextDayDelivery being set to 1 based on the StdDayDelivery being set to 1. If todays date was the 2014-07-12 then the results will start from the 14th as the 13th is a Sunday so the next available delivery day is the 14th so again, NextDayDelivery is a 1 on the 14th.
I hope this is making sense.
The two expected outputs would be:
If today is the Friday the 11th, the results would be:
2014-07-12 1 1
2014-07-13 0 0
2014-07-14 0 1
2014-07-15 0 1
2014-07-16 0 1
2014-07-17 0 1
2014-07-18 0 1
If today is the Sat the 12th, the results would be:
2014-07-13 0 0
2014-07-14 1 1
2014-07-15 0 1
2014-07-16 0 1
2014-07-17 0 1
2014-07-18 0 1
(13th values set to 0 as StdDayDelivery is showing 0 because it's a sunday)

Answer 1

Looks like that CROSS APPLY may help you with this task.
Create table function for [NextDayDelivery] calculation
IF OBJECT_ID(N'dbo.GetData', N'TF') IS NOT NULL
DROP FUNCTION dbo.GetData;
GO
CREATE FUNCTION GetData(#ScheduleDate AS DATETIME, #testDay AS DATETIME)
RETURNS #VV TABLE
(
[NextDayDelivery] bit
)
AS
BEGIN
INSERT INTO #VV
SELECT
CASE
WHEN (DATEDIFF(dd, #testDay, #ScheduleDate)=1 AND DATEPART(dw, #ScheduleDate)>1) OR
(DATEDIFF(dd, #testDay, #ScheduleDate)=2 AND DATEPART(dw, #testDay)=7) THEN 1
ELSE 0
END
AS [NextDayDelivery]
RETURN
END
GO
Use this function in SELECT
DECLARE #testDay DATETIME
SET #testDay = DATEADD(d,1,GETUTCDATE())
-- SET #testDay = GETUTCDATE()
SELECT t.[ScheduleDate], VV.[NextDayDelivery], t.StdDayDelivery
FROM [tbl_Sys_QuickstartDeliveryQuota] AS t
CROSS APPLY GetData(t.[ScheduleDate], #testDay) AS VV
where t.[ScheduleDate] > #testDay
Note: My code supposes that first day of week is Sunday. I.e. SELECT DATEPART(dw, '2014-07-12') returns me 7. Correct my code if you use other culture.