Count specific items in one column

Question

I have a table called ratings, and a column called item_id. I simply would like to group each individual item together and count them.

For example:

if there are 1000 rows, and item_id 51 has been rated 20 times, and item_id 14 has been rated 7 times and item_id 33 has been rated 2 times, I simply want it to be grouped in DESC like:

item_id 51 item_id 7 item_id 33

I tried to follow something like this question, but could not get it to work.

Answer 1

SELECT item_id, COUNT(*) AS count
FROM ratings 
GROUP BY item_id
ORDER BY count DESC;

Answer 2

SELECT * 
FROM (
    SELECT item_id, COUNT(rating) AS rating
    FROM ratings GROUP BY item_id
) a
GROUP BY a.rating DESC

Answer 3

SELECT count(*) AS counter, item_id
FROM ratings
GROUP BY item_id 
ORDER BY counter DESC