Ronald McDonald :
Im trying to get the groups where the brand_id's match exactly to the group.
I've tried this solution (see fiddle) but when i try to obtain one item that has a brand id that is assigned to all the groups it shows all three groups. But it should match zero, because its not an exact match.
http://sqlfiddle.com/#!9/a5b16e/2/0
I was wondering if there is a solution to this
SELECT group_id as groep
FROM mailgroups a
WHERE a.brand_id IN (2)
GROUP BY a.group_id
HAVING COUNT(*) = 1
this should return group 3
SELECT group_id as groep
FROM mailgroups a
WHERE a.brand_id IN (2, 1)
GROUP BY a.group_id
HAVING COUNT(*) = 2
and this should only return group_id 1
forpas :
You don't need subqueries or joins.
Set the correct conditions in the having
clause and remove the where
clause:
SELECT group_id as groep
FROM mailgroups
GROUP BY group_id
HAVING SUM(brand_id IN (2)) = 1 AND SUM(brand_id NOT IN (2)) = 0;
SELECT group_id as groep
FROM mailgroups
GROUP BY group_id
HAVING SUM(brand_id IN (1, 2)) = 2 AND SUM(brand_id NOT IN (1, 2)) = 0;
See the demo.