How to calculate a daily running total from an aliased column - sql-server

Question

I'm writing a query to return a table of booking data for an event. I've used a SUM aggregate to group the number of daily bookings. I'd now like to create a column with a cumulative running total.
I can't make my query work because (I'm presuming) it doesn't like the aliased column title being included in the aggregate function.
Please can anyone advise me on the best approach to make this work?
SELECT
'Recruitment Event' Event,
CAST(ep.CREATIONDATE AS date) AS 'Date of Booking',
SUM(CASE
WHEN ep.CREATIONDATE IS NOT NULL THEN 1
ELSE 0
END) 'Total Bookings',
(SELECT
SUM('Total Bookings')
FROM EVENTPLACE AS ep
WHERE CAST(ep.CREATIONDATE AS date) <= CAST(ep.CREATIONDATE AS date))
'Running Total'
FROM EVENTPLACE AS ep
LEFT JOIN EVENTMODULE AS em
ON em.EVENTMODULENO = ep.EVENTMODULENO
WHERE em.EVENTMODULENO = '11111111-ABCD-1234-1234-1010101010'
GROUP BY CAST(ep.CREATIONDATE AS date)
ORDER BY CAST(ep.CREATIONDATE AS date) DESC

Answer 1

try this
SELECT
[Event] = 'Recruitment Event' ,
[Date of Booking] = CAST(ep.CREATIONDATE AS DATE),
[Total Bookings] = COUNT(ep.CREATIONDATE),
[Running Total] = SUM(COUNT(ep.CREATIONDATE)) OVER (ORDER BY CAST(ep.CREATIONDATE AS DATE) DESC)
FROM
EVENTPLACE AS ep
WHERE
EXISTS (SELECT
*
FROM
EVENTMODULE em
WHERE
em.EVENTMODULENO = ep.EVENTMODULENO
AND em.EVENTMODULENO = '11111111-ABCD-1234-1234-1010101010')
GROUP BY
CAST(ep.CREATIONDATE AS DATE)
ORDER BY
CAST(ep.CREATIONDATE AS DATE) DESC
COUNT(ep.CREATIONDATE) will ignore null values with the same result as your SUM(CASE)
You dont really have to use EXISTS, but you should probably change your LEFT JOIN to a JOIN since you're using the em.EVENTMODULENO in the WHERE statement
SUM(COUNT(ep.CREATIONDATE)) OVER () will give you running total of the count. You use ORDER BY in the OVER to determine the order of the SUM. Since you're ordering by CAST(ep.CREATIONDATE AS DATE) DESC you can just use that in the OVER()

Answer 2

You are getting error because of these lines..
SUM (case when ep.CREATIONDATE IS NOT NULL then 1 else 0 end) 'Total Bookings',
(SELECT SUM ('Total Bookings') FROM EVENTPLACE
You are trying to select alias which was defined in same phase and you are passing it as string .your query wont work unless you correlate it with main table which you are not doing..
Below query works from SQLServer 2012
;with cte
as
(
SELECT 'Recruitment Event' Event,
cast(ep.CREATIONDATE as date) as 'Date of Booking',
SUM (case when ep.CREATIONDATE IS NOT NULL then 1 else 0 end) 'Total Bookings',
FROM EVENTPLACE as ep
LEFT JOIN EVENTMODULE as em ON em.EVENTMODULENO=ep.EVENTMODULENO
WHERE em.EVENTMODULENO = '11111111-ABCD-1234-1234-1010101010'
GROUP BY cast(ep.CREATIONDATE as date)
)
select *,
sum([Total Bookings])
over (order by [Date of Booking] ROWS UNBOUNDED ECEDING ) as 'Runningtotal'
from
cte

Answer 3

The problem is that there is a SUM() function in your select statement, but not all the other columns are included in your group by clause.
The solution is that add an OVER(ORDER BY ...) clause after your SUM function to calculate the running total.
SELECT
'Recruitment Event' Event,
CAST(ep.CREATIONDATE AS date) AS 'Date of Booking',
SUM(CASE
WHEN ep.CREATIONDATE IS NOT NULL THEN 1
ELSE 0
END)OVER(ORDER BY CAST(ep.CREATIONDATE AS date) DESC) 'Running Total',
FROM EVENTPLACE AS ep
LEFT JOIN EVENTMODULE AS em
ON em.EVENTMODULENO = ep.EVENTMODULENO
WHERE em.EVENTMODULENO = '11111111-ABCD-1234-1234-1010101010'
CAST(ep.CREATIONDATE AS date) DESC