Loops on SQL Server - sql-server

Question

I have the following query where I input a date and it give me the result. However, I need to run this for 60 different dates. Instead of running this 1 by 1, is there anyway to automate this so it runs each time on a different date?
IF OBJECT_ID('tempdb..#1') IS NOT NULL DROP TABLE #1
declare #d1 datetime = '2020-02-06'
select distinct [User] into #1
from [X].[dbo].[Table1]
where [status] = 'Success'
and [Date] = #d1;
select count(distinct [User])
from #1
inner join [Y].[dbo].[Table2]
on #1.[User] = [Y].[dbo].[Table2].User
where [Date2] between #d1 and #d1+1
and [Checkname] in ('Check1','Check2')

Answer 1

Loops are slow and generally a bad practice in the context of T-SQL. You can use something like this to get the count of users for a batch of dates:
DROP TABLE IF EXISTS #DataSource;
CREATE TABLE #DataSource
(
[Date] DATETIME
,[UsersCount] INT
);
INSERT INTO #DataSource ([Date])
VALUES ('2020-02-06')
,('2020-02-07')
,('2020-02-08');
IF OBJECT_ID('tempdb..#1') IS NOT NULL DROP TABLE #1
select distinct DS1.[Date]
,DS1.[User]
into #1
from [X].[dbo].[Table1] DS1
INNER JOIN #DataSource DS2
ON DS1.[Date] = DS2.[Date]
where DS1.[status] = 'Success';
select #1.[date]
,count(distinct [User])
from #1
inner join [Y].[dbo].[Table2]
on #1.[User] = [Y].[dbo].[Table2].User
where [Date2] between #1.[date] and #1.[date] + 1
and [Checkname] in ('Check1','Check2')
GROUP BY #1.[date]

Answer 2

First, I want to say that gotqn's answer is a good answer - however, I think there are a few more things in the original code that can be improved - so here is how I would probably do it:
Assuming the dates are consecutive, use a common table expression to calculate the dates using dateadd and row_number.
Then, use another common table expression to get the list of dates and users from table1,
and then select the date and count of distinct users for each date from that common table expression joined to table2:
DECLARE #StartDate Date = '2020-02-06';
WITH Dates AS
(
SELECT TOP (60) DATEADD(DAY, ROW_NUMBER() OVER(ORDER BY ##SPID) -1, #StartDate) As Date
FROM sys.objects
), CTE AS
(
SELECT t1.[User], t1.[Date]
FROM [X].[dbo].[Table1] AS t1
JOIN Dates
ON t1.[Date] = Dates.[Date]
WHERE [status] = 'Success'
)
SELECT cte.[Date], COUNT(DISTINCT [User])
FROM CTE
JOIN [Y].[dbo].[Table2] As t1
ON CTE.[User] = t1.[User]
AND t1.[Date2] >= CTE.[Date]
AND t1.[Date2] < DATEADD(Day, 1, CTE.[Date])
AND [Checkname] IN ('Check1','Check2')
GROUP BY cte.[Date]
If the dates are not consecutive, you can use a table variable to hold the dates instead of calculating them using a common table expression.