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

I think you may have the "userid = itemid" wrong, shouldn't it be like this:

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