每月各类别新主题

社区 数据与报告
1

每月各类别的新主题数量

返回给定月份中每个类别创建的新主题数量，按主题数量排序。该查询接受一个“几个月前”的参数，默认为 0，以返回当前月份的结果。

-- [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
)

SELECT
    t.category_id,
    count(1) as topic_count
FROM topics t
RIGHT JOIN query_period qp
    ON t.created_at >= qp.period_start
        AND t.created_at <= qp.period_end
WHERE t.user_id > 0
    AND t.category_id IS NOT NULL
GROUP BY t.category_id
ORDER BY topic_count DESC