项目和类别（1：N）如何在单个SQL查询中获取每个类别的活动项目总数和总数量？

COUNT(items.active) AS items_total,
SUM(items.active)   AS items_active,
SUM(1-items.active) AS items_inactive

SUM(CASE WHEN items.active = 0 THEN 1 ELSE 0 END) as items_inactive

select items.id
 , COUNT(items.active) AS items_total
 , SUM(ifnull(items.active,0)) AS items_active
 , SUM(1-ifnull(items.active,0)) AS items_inactive
FROM items
GROUP BY items.somefield WITH ROLLUP

+------+-------------+---------------+----------------+
| id   | items_total | items_active  | items_inactive |
+------+-------------+---------------+----------------+
| 1    | 2           | 1             | 1              |
| 2    | ....
| null |100          | 60            | 40             |<<- grand total
+------+-------------+---------------+----------------+

with rollup