sql

select a.secondcategory,b.secondcategory,count(a.device)
from (
select a.secondcategory,a.device  
from q2game_category a
where 
secondcategory like '%休闲%'
group by secondcategory,device
) a
join (
select b.secondcategory,b.device  
from q2game_category b
where secondcategory like '%体育%'
group by secondcategory,device
) b 
on a.device=b.device
group by a.secondcategory,b.secondcategory

不知道为什么我们能够单独拉出来休闲和体育的数据，但是我们做交叠的时候数据就是空的，但是应该是有数据的啊。