I 50 migliori autori
Restituisce i 50 autori con più post per un determinato periodo mensile. I risultati sono ordinati per post_count. Accetta un parametro months_ago, che di default è 0 per fornire i risultati del mese corrente.
-- [params]
-- int :months_ago = 1
WITH query_period AS (
SELECT
date_trunc('month', CURRENT_DATE) - INTERVAL ':months_ago months' as period_start,
date_trunc('month', CURRENT_DATE) - INTERVAL ':months_ago months' + INTERVAL '1 month' - INTERVAL '1 second' as period_end
),
user_posts_in_period AS (
SELECT
p.user_id
FROM posts p
INNER JOIN query_period qp
ON p.created_at >= qp.period_start
AND p.created_at <= qp.period_end
WHERE p.user_id > 0
)
SELECT
up.user_id,
count(1) as post_count
FROM user_posts_in_period up
GROUP BY up.user_id
ORDER BY post_count DESC
LIMIT 50