T-SQL Date Range Selection - sql-server

Question

I have a SQL Server database with this table:
and I am trying to get RatePrice between specific dates for a certain TypeID e.g.
DECLARE #StartDate DATE = '2022-02-26';
DECLARE #EndDate DATE = '2022-03-02';
DECLARE #TypeID int = 10;
DECLARE #RatePrice money;
DECLARE #RateDate DATE;
WHILE (#StartDate <= #EndDate)
BEGIN
SELECT
#RatePrice = RatePrice,
#RateDate = #StartDate
FROM mgaRate
WHERE mgaRate.TypeID = #TypeID
AND ((RateStart BETWEEN #StartDate AND #EndDate) OR
(RateEnd BETWEEN #StartDate AND #EndDate) OR
(RateStart <= #StartDate AND RateEnd >= #EndDate)
)
PRINT #RateDate;
PRINT #RatePrice;
SET #StartDate = DATEADD(day, 1, #StartDate);
END;
But the result is not correct:
2022-02-26
400.00
2022-02-27
400.00
2022-02-28
400.00
2022-03-01
400.00
2022-03-02
400.00
In February the price should show 300.00.

Answer 1

You can use a calendar table to get all the dates in the range you need, and for each date you can get the rate using a subquery from the original table:
DECLARE #StartDate DATE = '2022-02-26';
DECLARE #EndDate DATE = '2022-03-02';
DECLARE #TypeID int = 10;
with calendar as (
select #StartDate as d
union all
select dateadd(day, 1, d)
from calendar
where d < #EndDate
)
select
d,
(select RatePrice
from mgaRate
where d between RateStart and RateEnd
and TypeID = #TypeID)
from calendar
You can replace the recursive CTE with an actual calendar table.
Fiddle