SQL reflect data for all days - sql

Question

I am trying to create a table in SQL where I reflect data for all days of a particular month.
For example, even if there is no Sale transaction for a particular day, the day for the particular employee should still be reflective in the table.
Scenario for the question. I am working with the following dates for this example: 1st, 2nd, 3rd and 4th Jan 2022.
The raw data is as follows:
Name
Date
SaleAmount
John
2022-01-01
154875
John
2022-01-03
598752
As seen above, we only have data for the 1st and 3rd.
The outcome should look as follows:
Name
Date
SaleAmount
John
2022-01-01
154875
John
2022-01-02
NULL
John
2022-01-03
598752
John
2022-01-04
NULL
As seen above, the 2nd and 4th should be included even though there was no activity for those days.
What I am currently trying:
I have a master date table which is being used as a RIGHT JOIN on the transaction table. However, the final outcome of my table is as follows:
Name
Date
SaleAmount
John
2022-01-01
154875
NULL
2022-01-02
NULL
John
2022-01-03
598752
NULL
2022-01-04
NULL
As seen above, the 'Name' field returns as NULL. The SaleAmount however should reflect NULL to indicate no transactions happening.
I would appreciate any assistance on this.

Answer 1

Seems like you want to
Start with the date table
Cross join to your employee/salesperson table so you now have one row for each salesperson on each date
Left join the sales orders for that date + salesperson combo to get the sum of their sales for that day. If they have none, it'll show null:
select emp.Name
,dat.Date
,sum(ord.Amount) as SaleAmount
from dateList dat
cross join salesPerson emp
left join salesOrder ord on ord.OrderDate = dat.Date and ord.SalesPersonId = emp.SalesPersonId
group by emp.Name
,dat.Date

Answer 2

you can create a list of dates on the fly. as example per month
Declare #year int = 2022, #month int = 7;
WITH numbers
as
(
Select 1 as value
UNion ALL
Select value + 1 from numbers
where value + 1 <= Day(EOMONTH(datefromparts(#year,#month,1)))
)
SELECT datefromparts(#year,#month,numbers.value) Datum FROM numbers
then left join to your table.

Answer 3

You may use a Recursive CTE as the following:
Declare #startDate as date ='2022-01-01';
Declare #endDate as date ='2022-01-31';
With CTE As
(
Select Distinct Name_ nm,#startDate dt From SalesDates
Where Date_ Between #startDate And #endDate
Union All
Select nm, DateAdd(Day,1,dt) From CTE
Where DateAdd(Day,1,dt)<=#endDate
)
Select C.nm as [Name],C.dt as [Date], S.SaleAmount
From CTE C Left Join SalesDates S
On S.Date_=C.dt
And S.Name_=C.nm
Order By C.nm,C.dt
You can change the values of #startDate and #endDate according to the period you want.
See a demo from db<>fiddle.