Get Sum of all Distinct in a week - sql

Question

I am wondering where exactly i am not clear with this query. I want to get the count of all distinct RepIDs that worked in a particular week. This is In SQL Server 2005. Thank you!!
This query gives me distinct RepID's for the whole week. I want to count RepID twice if he has records on 2 different days but count only once even if he has more than 1 record for any partiular day.. I hope i am clear. I am sorry that i was not clear before! Thank you!
Select count(distinct(RepID)) as SalesPeople from DailyInfo
where Date > DATEADD(dd, -(DATEPART(dw, #Date)-1), #Date)
and Date < DATEADD(dd, 7-(DATEPART(dw, #Date)), #Date)

Answer 1

You can make unique combinations of the RepID+Date to make it unique (SQLFiddle):
SELECT COUNT(distinct RIGHT(DateDiff(d,0,Date),10)
+RIGHT(RepID,10)) as SalesPeople
FROM DailyInfo
WHERE Date > DATEADD(dd, -(DATEPART(dw, #Date)-1), #Date)
AND Date < DATEADD(dd, 7-(DATEPART(dw, #Date)), #Date);
I have assumed DailyInfo.Date can contain time information. You can swap DateDiff(d,0,Date) above for just Date. Similarly, CAST(DateDiff(d,0,Date) as datetime) below can be just `Date.
Below is the query if you needed to see the breakdown for each day.
SELECT CAST(DateDiff(d,0,Date) as datetime) TheDay,
COUNT(distinct RepID) as SalesPeople
FROM DailyInfo
WHERE Date > DATEADD(dd, -(DATEPART(dw, #Date)-1), #Date)
AND Date < DATEADD(dd, 7-(DATEPART(dw, #Date)), #Date)
GROUP BY CAST(DateDiff(d,0,Date) as datetime) -- by day
ORDER BY TheDay

Answer 2

Let me answer this by suggesting how you should think about the problem. You are looking for the number of reps per day. So, your query should have a summary (subquery) at this level. Then, you can count the number of days per week.
Assuming that your date does not have any time component, you can use the following:
select count(*)
from (select RepId, date as thedate, count(*) as NumOnDay
from DailyInfo
group by RepId, date
where Date > DATEADD(dd, -(DATEPART(dw, #Date)-1), #Date)
and Date < DATEADD(dd, 7-(DATEPART(dw, #Date)), #Date)
) rd
Alternatively, you could count the number of days that a rep worked during a week and then add these up:
select sum(numdates)
from (select RepId, count(distinct date) as numdates
from DailyInfo
group by RepId
where Date > DATEADD(dd, -(DATEPART(dw, #Date)-1), #Date)
and Date < DATEADD(dd, 7-(DATEPART(dw, #Date)), #Date)
) rd
If your date field has a time component, then you need to remove the time component for this to work. Or use some trick such as day(date), since the day function will returns a different value for each date in a week. In later versions of SQL Server, you can just cast(date as date), if the original date is datetime.

Answer 3

Select count(1)
from DailyInfo
group by convert(varchar(10),[date], 120)
where [put your condition here]

Answer 4

You could use a CTE, but might be over kill. And have the group by the day in the CTE and you need to do is a sum of the totals.
WITH cte ([day], total) as
(
Select DATENAME(DW,[Date]), count(distinct(RepID)) as SalesPeople from DailyInfo
where [Date] > DATEADD(dd, -(DATEPART(dw, #Date)-1), #Date) and [Date] < DATEADD(dd, 7-(DATEPART(dw, #Date)), #Date)
GROUP BY DATENAME(DW,[Date])
)
select SUM(total) FROM cte;

Answer 5

To do what I think you want you need to group by day, and filter on the week, and then do a distinct on the result:
Select Distinct(RepID)
From (Select RepID
Group By DateDiff(day, 0, Date)
From DailyInfo
Where Date > DateAdd(dd, -(DATEPART(dw, #Date)-1), #Date)
And Date < DateAdd(dd, 7-(DATEPART(dw, #Date)), #Date)