-- sms.csv
declare @StartDate date = '2014-01-01';
declare @EndDate date = '2020-01-01';
WITH cte AS (
SELECT IIF(DATEPART(Day, @StartDate) = 1, @StartDate, DATEADD(Month, DATEDIFF(Month, 0, @StartDate) + 1, 0)) AS myDate
UNION ALL
SELECT DATEADD(Month,1,myDate)
FROM cte
WHERE DATEADD(Month,1,myDate) <  @EndDate
)
SELECT cast(myDate as DATE) as d,
       DATEPART(year, myDate) as y,
       count(s.s_id) as c
FROM cte c
inner join ops_sms s on year(s_sendDate) = year(c.myDate) and month(s_sendDate) = month(c.myDate)
group by myDate
order by myDate
OPTION (MAXRECURSION 0)