how to use count, case and Distinct together in sql server - sql-server

Question

I want to create a statement but i not success to complete this. can you please take a look and let me know what i need to do to complete this. My problem due how to add these two part in my query.
I want to look at the last 30 days of orders for each DRV1NUM. If that driver has worked 0 days then say ‘NOT ACTIVE’. If the driver has worked more than 15 days then ‘FULL TIME’ and less than 15 days is ‘PART TIME’.
In this one, I want to look at the last 30 days of orders and compare the left(4) of DRIVERNUM to the entire DRIVERNUM. In some instances, we have drivers where there is a 5th letter after the left 4.I want to look at the last 30 days of orders and if the left(4) DRV1NUM has more than one DRV1NUM WHEN looking at all characters, then SAY ‘MASTER’
SELECT DISTINCT DRVLICNUM,DOB,COUNTRY,CREDITLIMIT,DRIVERNUM=LEFT(DRIVERNUM,4),
SSN,D.VEHICLE,PHN1,DRVLICST,HOST,VEHICLE_MC,
VEHICLE_DOT,BACK_APPROVED=CASE WHEN PROBDATE IS NOT NULL THEN 'YES' ELSE 'NO' END
-- CASE WHEN COUNT(DISTINCT O.DROPDATE)=0 IN LAST 30 DAYS THEN 'NOT ACTIVE' WHEN COUNT(DISTINCT O.DROPDATE)>15 IN LAST 30 DAYS THEN 'FULL TIME' WHEN COUNT(DISTINCT O.DROPDATE)>=1 AND <=15 THEN 'PART TIME' IN LAST 30 DAYS ELSE NULL AS DAYSWORKED,
-- --CASE WHEN COUNT(DISTINCT O.DRV1NUM OF LEFT(DRIVERNUM,4 )>0 IN LAST 30 DAYS OF ORDERS>1 THEN 'MASTER IC' ELSE NULL AS MASTER
/* ABOVE TWO STATEMENT I WANT TO ADD */
FROM DRIVER D
FULL OUTER JOIN orde_ O ON O.DRV1ID=D.DRIVERID
AND ISNUMERIC(DRIVERNUM)=1 and DRIVERNUM NOT IN ('1010')
Expected Output That i want
DRVLICNUM Employee DOB COUNTRY ACTIVESTATUS
---------------------------------------------------------
055243324 CONTRACTOR 1985-04-13 ATLANTA FULL TIME
Here the ActiveStatus is Active because the driver worked more than 15 days in past 15 days or if it will less then 15 days it will be 'Part Time'

Answer 1

I don't have access to google drive link which you shared.
However, you will have to use CTE (common table expression) to get count of days and then use it compute value of ActiveStatus column.
Try using below code:
;
WITH CTE1
AS(
SELECT D.DRIVERID,
COUNT(DISTINCT O.DROPDATE) AS DayCount
FROM DRIVER AS D
LEFT JOIN ORDER AS O ON D.DRIVERID=O.DRV1ID AND O.DROPDATE BETWEEN CONVERT(DATE,DATEADD(DAY,-30,GETDATE())) AND GETDATE()
WHERE ISNUMERIC(D.DRIVERNUM)=1 AND D.DRIVERNUM NOT IN ('1010')
GROUP BY D.DRIVERID
)
SELECT DRVLICNUM,DOB,COUNTRY,CREDITLIMI,...
CASE
WHEN DayCount=0 THEN 'NOT ACTIVE'
WHEN DayCount<=15 THEN 'PART TIME'
WHEN DayCount>=30 THEN 'FULL TIME'
END AS ACTIVESTATUS
FROM CTE1 AS C
JOIN DRIVER AS D ON C.DRIVERID=D.DRIVERID

Answer 2

here is two siple queries for the first one:
1) select order by dates and group by driver (if there no more than one order per day):
select o.DRIVERID
, count(*) as cnt
from orde_ o
where o.DROPDATE betwen GETDATE() AND DATEADD(DAY,-30,GETDATE())
group by o.DRIVERID
2) select drivers and join groupped orders
select case
when o.ctn >= 15 then 'FULL TIME'
when o.ctn > 0 then 'PART TIME'
else 'NOT ACTIVE'
end
, <other fields you want>
from DRIVER as D
left join <query above> as o
on o.DRIVERID = d.DRIVERID
for the second one:
select left(d.DRIVERID, 4), count(*) as cnt
from DRIVER as D
group by left(d.DRIVERID, 4)
having count(*) > 1
and just join it, if is not null then compare whole id's