Using GROUP_CONCAT on subquery in MySQL

Question

I have a MySQL query in which I want to include a list of ID\'s from another table. On the website, people are able to add certain items, and people can then add those items to

Answer 1

The purpose of GROUP_CONCAT is correct but the subquery is unnecessary and causing the problem. Try this instead:

SELECT ITEMS.id,GROUP_CONCAT(FAVOURITES.UserId)
FROM FAVOURITES INNER JOIN ITEMS ON ITEMS.Id = FAVOURITES.ItemId
WHERE ITEMS.Id = $someid
GROUP BY ITEMS.ID