How to insert multiple rows into a table based on a range of numbers

Question

I have to insert a specific number of rows into a SQL Server table.

DECLARE @val AS INT = 20, 
        @val2 AS VARCHAR(50), 
        @Date AS DATETIME = CONVER         


        

Answer 1

Besides the detailed answer I pointed to in my comment, this is the idea in short:

DECLARE @start INT=0;
DECLARE @end INT=19; --0 to 19 are 20 days

DECLARE @StartDate DATE={d'2016-01-01'};

--Create a List of up to 1.000.000.000 rows on the fly
--This is limited by start and end parameter

;WITH x AS(SELECT 1 AS N FROM(VALUES(1),(1),(1),(1),(1),(1),(1),(1),(1),(1)) AS tbl(N))--10^1
,N3 AS (SELECT 1 AS N FROM x CROSS JOIN x AS N2 CROSS JOIN x N3) --10^3
,Tally AS(SELECT TOP(@end-@start +1) ROW_NUMBER() OVER(ORDER BY(SELECT NULL)) + @start -1 AS Nr FROM N3 
          CROSS JOIN N3 N6 CROSS JOIN N3 AS N9)

--INSERT INTO your_table

SELECT @val2 --your @val2 here as a constant value
      ,DATEADD(DAY,Nr,@StartDate)
FROM Tally