Query with group by with CustID and amounts daily and MTD - sql

Question

I have the following data:
ID
username
Cost
time
1
test1
1
2021-05-22 11:48:36.000
2
test2
2
2021-05-20 12:55:22.000
3
test3
5
2021-05-21 00:00:0-0.000
I would like to count the costs for the username with a daily figure and a month to date figure in once table
I have got the following
SELECT
username,
COUNT(*) cost
FROM
dbo.sent
WHERE
time BETWEEN {ts '2021-05-01 00:00:00'} AND {ts '2021-05-22 23:59:59'}
GROUP BY
username
ORDER BY
cost DESC;
This will return the monthly figures and changing the time to '2021-05-22 00:00:00'} AND {ts '2021-05-22 23:59:59'} will give the the daily however I would like a table to show daily and MTD together
username
Daily
MTD
test1
1
1012
test2
2
500
test3
5
22
Any help or pointers would be fantastic, I am guessing that I need a temp table and then run again using the MTD range updating the temp table where the username is the same then to export and delete - but i have no idea where to start.

Answer 1

First, you need one row per user and date, not just one row per user.
Second, you should fix your date arithmetic so you are not missing a second.
Then, you can use aggregation and window functions:
SELECT username, CONVERT(DATE, time) as dte,
COUNT(*) as cost_per_day,
SUM(COUNT(*)) OVER (PARTITION BY username ORDER BY CONVERT(DATE, time)) as mtd
FROM dbo.sent s
WHERE time >= '2021-05-01' AND
time < '2021-05-23'
GROUP BY username, CONVERT(DATE, time)
ORDER BY username, dte;
You can learn more about window functions in a SQL tutorial (or, ahem, a book on SQL) or in the documentation.
EDIT:
If you only want the most recent date and MTD, then you can either filter the above query for the most recent date or use conditional aggregation:
SELECT username,
SUM(CASE WHEN CONVERT(DATE, time) = '2021-05-22' THEN 1 ELSE 0 END) as cost_per_most_recent_day,
COUNT(*) as MTD
FROM dbo.sent s
WHERE time >= '2021-05-01' AND
time < '2021-05-23'
GROUP BY username
ORDER BY username;
And, you can actually express the query using the current date so it doesn't have to be hardcoded. For this version:
SELECT username,
SUM(CASE WHEN CONVERT(DATE, time) = CONVERT(DATE, GETDATE()) THEN 1 ELSE 0 END) as cost_per_most_recent_day,
COUNT(*) as MTD
FROM dbo.sent s
WHERE time >= DATEFROMPARTS(YEAR(GETDATE()), MONTH(GETDATE()), 1) AND
time < DATEADD(DAY, 1, CONVERT(DATE, GETDATE()))
GROUP BY username
ORDER BY username;