SELECT
json_agg(json_build_object(name, cnt)) AS films_by_category
FROM (
SELECT
c.name,
COUNT(f.film_id) AS cnt
FROM
film f
INNER JOIN
film_category fc ON f.film_id = fc.film_id
INNER JOIN
category c ON fc.category_id = c.category_id
GROUP BY
c.name
) AS categories;
;
show status like 'Last_query_cost';