sql 表的合并

select sum(cnt1),sum(cnt2)
from
(SELECT u.f_id,u.f_username, COUNT( * ) AS cnt1,0 as cnt2
FROM  `t_customer` c
LEFT JOIN app_user u ON u.f_id = c.f_user_id
group by f_id
union all
SELECT  u.f_id,u.f_username, 0 as cnt1,COUNT( * ) AS cnt2
FROM  `t_weibo` w
LEFT JOIN app_user u ON u.f_id = w.f_created_by
LEFT JOIN t_customer c ON c.f_id = w.f_customer_id
group by f_id
) tmp

group by f_id

这样就实现了表的行合并与”列合并“