combine two sql queries having each a with clause - sql

Question

I have got two queries who are doing the job for me but I would like to combine them to have the results in one table instead of copy past the results into excel.
First query gives me the number of users whose at least one subscription have expired per month in 2018:
WITH UniqueUsers AS
(
SELECT DISTINCT MONTH(ValidTo) ExpireMonth, UserId
FROM UserInAppPurchase
WHERE YEAR(ValidTo) = 2018
)
SELECT ExpireMonth, COUNT(UserId) UserCount
FROM UniqueUsers
GROUP BY ExpireMonth order by ExpireMonth;
Second query gives me the number of users whose at least made one subscription purchase per month in 2018:
WITH UniqueUsers AS
(
SELECT DISTINCT MONTH(PurchaseDate) PurchaseMonth, UserId
FROM UserInAppPurchase
WHERE YEAR(PurchaseDate) = 2018
)
SELECT PurchaseMonth, COUNT(UserId) UserCount
FROM UniqueUsers
GROUP BY PurchaseMonth order by PurchaseMonth;
Actually the PurchaseMonth and ExpireMonth are the same.
My expected output is: 1st column: months of 2018
2nd column: results from first query
3nd column: results from second query
It is not a big harm to just copy the two results and combine them manually, but I am curious how to do it directly in SQL.
Thanks for the help

Answer 1

I would unpivot the dates and just do aggregation:
SELECT MONTH(dte) as mon,
COUNT(DISTINCT ExpireUserId) as numExpiredUsers,
COUNT(DISTINCT PurchaseUserId) as numPurchaseUsers
FROM UserInAppPurchase uiap CROSS APPLY
(VALUES (ValidTo, UserId, NULL),
(PurchaseDate, NULL, UserId)
) v(dte, ExpireUserId, PurchaseUserId)
WHERE dte >= '2018-01-01' AND dte < '2019-01-01'
GROUP BY MONTH(dte)
ORDER BY MONTH(dte);
No subqueries, explicit JOINs, or CTEs are really needed for this logic.

Answer 2

You can use smth like this:
with months as
(
SELECT MONTH(ValidTo) as month_
FROM UniqueUsers
WHERE YEAR(ValidTo) = 2018
union
SELECT MONTH(PurchaseDate)
FROM UniqueUsers
WHERE YEAR(PurchaseDate) = 2018
),
UniqueUsers AS
(
SELECT MONTH(PurchaseDate) as ExpireMonth,
COUNT(UserId) UserCount
FROM UniqueUsers
WHERE YEAR(ValidTo) = 2018
GROUP BY MONTH(PurchaseDate)
),
UniqueUsers1 AS
(
SELECT MONTH(PurchaseDate) as PurchaseMonth,
COUNT(UserId) UserCount1
FROM UniqueUsers
WHERE YEAR(PurchaseDate) = 2018
GROUP BY MONTH(PurchaseDate)
)
select m.month_,
u.UserCount,
u1.UserCount1
from months m
left join UniqueUsers u
on m.month_ = u.ExpireMonth
left join UniqueUsers1 u1
on m.month_ = u1.PurchaseMonth
order by m.month_;
But I'm not sure your order by clause is what you want. Your months will be sorted as 1, 11, 12. Maybe you wanted another order, I just rewrote your queries in order to combine them.

Answer 3

Here you are, you can join CTEs
;WITH UniqueUsers1
AS (
SELECT DISTINCT MONTH(ValidTo) ExpireMonth
,UserId
FROM UserInAppPurchase
WHERE YEAR(ValidTo) = 2018
)
,UniqueUsers2
AS (
SELECT DISTINCT MONTH(PurchaseDate) PurchaseMonth
,UserId
FROM UserInAppPurchase
WHERE YEAR(PurchaseDate) = 2018
)
SELECT *
FROM (
SELECT ExpireMonth
,COUNT(UserId) UserCount
FROM UniqueUsers1 c1
GROUP BY ExpireMonth
) First
INNER JOIN (
SELECT PurchaseMonth
,COUNT(UserId) UserCount
FROM UniqueUsers2
GROUP BY PurchaseMonth
) Sec ON First.ExpireMonth = Sec.PurchaseMonth

Answer 4

You can store each result in separate temporary table, for example create two temporary tables like this:
CREATE Table #ExpiryDates (ExpireMonth int, TotalUsers int)
CREATE Table #PurchaseDates (PurchaseMonth int, TotalUsers int)
And then store first query result into the temporary table #ExpirayDates
;WITH UniqueUsers AS
(
SELECT DISTINCT MONTH(ValidTo) ExpireMonth, UserId
FROM UserInAppPurchase
WHERE YEAR(ValidTo) = 2018
)
INSERT INTO #ExpiryDates (ExpireMonth, TotalUsers)
SELECT ExpireMonth, COUNT(UserId) UserCount
FROM UniqueUsers
GROUP BY ExpireMonth order by ExpireMonth;
Second Query will be like this:
;WITH UniqueUsers AS
(
SELECT DISTINCT MONTH(PurchaseDate) PurchaseMonth, UserId
FROM UserInAppPurchase
WHERE YEAR(PurchaseDate) = 2018
)
INSERT INTO #PurchaseDates (PurchaseMonth, TotalUsers)
SELECT PurchaseMonth, COUNT(UserId) UserCount
FROM UniqueUsers
GROUP BY PurchaseMonth order by PurchaseMonth;
Finally, compine these into one query
SELECT p.PurchaseMonth MonthNumber, p.TotalUsers As UsersMadePurchases,
e.ExpireMonth, e.TotalUsers As UsersExpiredSubs
FROM #PurchaseDates p
LEFT JOIN #ExpiryDates e
ON e.ExpireMonth = p.PurchaseMonth
Result will be:
MonthNumber UsersMadePurchases ExpireMonth UsersExpiredSubs
4 1 NULL NULL
5 2 5 2
6 2 6 2
7 1 7 1
8 1 8 1
Let me know if this solves your problem.