SQL Loop form between two days with ID - sql-server

Question

I Want to create loop between two days and USERID
For Example
If I Choose between 01-01-2017 and 05-01-2017
procedure already insert into my table days between for each user
every single user has a same days
I've tried the following
DECLARE #USERID int,#S_Date date,#E_Date date
SELECT #S_Date = #S_Date, #USERID = #USERID
While #S_Date <= #E_Date
begin
select #S_Date, #USERID
while #USERID < 3
begin
INSERT INTO myTable values(#S_Date, #USERID)
select #S_Date as S, #USERID as U
set #USERID = #USERID + 1
end
set #S_Date = DateAdd(Day, 1, #S_Date)
end

Answer 1

declare #fromdate date = '20170101'
declare #thrudate date = '20170105'
declare #from_UserId int = 1;
declare #thru_UserId int = 3;
;with n as (select n from (values(0),(1),(2),(3),(4),(5),(6),(7),(8),(9)) t(n))
, dates as (
select top (datediff(day, #fromdate, #thrudate)+1)
[Date]=convert(date,dateadd(day,row_number() over(order by (select 1))-1,#fromdate))
from n as deka cross join n as hecto cross join n as kilo
cross join n as tenK cross join n as hundredK
order by [Date]
)
insert into myTable ([Date],UserId)
select [Date], u.UserId
from dates
cross join (
select UserId
from Users u
where u.UserId >= #from_UserId
and u.UserId <= #thru_UserId
) u;
The above uses stacked ctes to generate a numbers table, and uses that numbers table to generate dates between the date range provided.
It might not look as simple as using a while loop, but it will perform much better.
rextester demo: http://rextester.com/HHY62656
returns:
+------------+--------+
| date | userid |
+------------+--------+
| 2017-01-01 | 1 |
| 2017-01-02 | 1 |
| 2017-01-03 | 1 |
| 2017-01-04 | 1 |
| 2017-01-05 | 1 |
| 2017-01-01 | 2 |
| 2017-01-02 | 2 |
| 2017-01-03 | 2 |
| 2017-01-04 | 2 |
| 2017-01-05 | 2 |
| 2017-01-01 | 3 |
| 2017-01-02 | 3 |
| 2017-01-03 | 3 |
| 2017-01-04 | 3 |
| 2017-01-05 | 3 |
+------------+--------+
Number and Calendar table reference:
Generate a set or sequence without loops - 2 - Aaron Bertrand
The "Numbers" or "Tally" Table: What it is and how it replaces a loop - Jeff Moden
Creating a Date Table/Dimension in sql Server 2008 - David Stein
Calendar Tables - Why You Need One - David Stein
Creating a date dimension or calendar table in sql Server - Aaron Bertrand