网友嫌弃俺用SUM，不用Count 。俺就举了这个例子。sum有时很方便，可以一个select 完成多个数据的统计。

declare @t table(usercode varchar(20),sex varchar(1) ,age int ,intern int ,city varchar(20) )
insert @t(usercode,sex,age,intern,city) values('001',1,55,0,'BJ')
insert @t(usercode,sex,age,intern,city) values('002',1,40,0,'BJ')
insert @t(usercode,sex,age,intern,city) values('003',1,24,0,'BJ')
insert @t(usercode,sex,age,intern,city) values('004',0,32,1,'SH')

select city as [城市] ,
       count(1) as [人数] , 
       sum(case when sex=0 then 1 else  0 end) as [人数（男）],
       sum(case when sex=1 then 1 else  0 end) as [人数（女）],
       sum(case when age>=45 then 1 else  0 end) as [人数（>=45岁）],
       sum(case when intern=1 then 1 else  0 end) as [实习生数]
from @t group by city