I have a table of "Songs", "Songs_Tags" (relating songs with tags) and "Songs_Votes" (relating songs with boolean like/dislike).
I need to retrieve the songs with a GROUP_CONCAT() of its tags and also the number of likes (true) and dislikes (false).
My query is something like that:
SELECT
s.*,
GROUP_CONCAT(st.id_tag) AS tags_ids,
COUNT(CASE WHEN v.vote=1 THEN 1 ELSE NULL END) as votesUp,
COUNT(CASE WHEN v.vote=0 THEN 1 ELSE NULL END) as votesDown,
FROM Songs s
LEFT JOIN Songs_Tags st ON (s.id = st.id_song)
LEFT JOIN Votes v ON (s.id=v.id_song)
GROUP BY s.id
ORDER BY id DESC
The problem is that when a Song has more than 1 tag, it gets returned more then once, so when I do the COUNT(), it returns more results.
The best solution I could think is if it would be possible to do the last LEFT JOIN after the GROUP BY (so now there would be only one entry for each song). Then I'd need another GROUP BY m.id.
Is there a way to accomplish that? Do I need to use a subquery?
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