Question

I have a fairly complicated SQL statement I am working on. Here is where I am at:

 SELECT  c.category
              FROM master_cat as c
        LEFT JOIN
            (
                SELECT cat_id, user_id COUNT(cat_id) favoriteCat
                FROM ratings
                GROUP BY user_id
            ) a ON a.cat_id= c.cat_id
        LEFT JOIN users AS u  
            ON  u.user_id AND a.user_id

WHERE u.username = '{$user}' LIMIT 1

This statement is incomplete. I am missing a middle table here. cat_id is not actually in ratings. But items_id is from a table called items and cat_id is also in that table as well.

So what I am trying to do is this:

SELECT rating FROM ??? GROUP BY cat_id where u.user=$user

The only thing I can think of doing maybe is another LEFT join with items inside favoriteCat but I am not sure if that is allowed.

Answer 1

I was overthinking this, here is my final solution:

SELECT  c.category,   count(r.rating) AS totalCount
FROM ratings as r
LEFT JOIN items AS i
   ON i.items_id = r.item_id
LEFT JOIN users AS u
   ON u.user_id = r.user_id
LEFT JOIN master_cat AS c
   ON c.cat_id = i.cat_id
WHERE  r.user_id = '{$user_id}'
GROUP BY c.category
ORDER BY totalCount DESC