How to also show counts that return 0?

Question

Hi,
I'm trying to count the number of users from some given countries. It goes like this:
select country_id,count(*) from user_registry
where user_id IN (307, 317,1472)
and country_id IN (0,2,3)
group by country_idThis is OK, and I get 2 users from country 0, and 1 user from country 2.
The problem is that I also want to get 0 from country 3 instead of nothing..
Is this possible? Thank you!

Answer 1

Something like this? (tested on 10g):
WITH user_registry AS (SELECT 307 user_id, 0 country_id
FROM dual
UNION
SELECT 317, 0
FROM dual
UNION
SELECT 1472, 2
FROM dual
country AS (SELECT 0 country_id
FROM dual
UNION
SELECT 2
FROM dual
UNION
SELECT 3
FROM dual
SELECT cty.country_id, Nvl(ur.count_user, 0)
FROM country cty,
(SELECT ur.country_id, count(*) count_user
FROM user_registry ur
WHERE ur.user_id IN (307, 317, 1472)
AND ur.country_id IN (0, 2, 3)
GROUP BY ur.country_id
) ur
WHERE cty.country_id = ur.country_id(+)
;C.
Formatting seems to be out of order sigh?!