sql语句问题
0
悬赏园豆：5
[已解决问题]
解决于 2011-03-11 07:44
以下表数据：
StuNo StuName
1 a
2 b
3 a
4 a
5 b
6 c
要求查询的结果是：
a的个数 b的个数 c的个数
3 2 1
请问sql语句怎么写了？？情大家帮忙
最佳答案
0
select StuName,sum(case StuName when 'a' then 1 else 0 end) as 'a的个数',
sum(case StuName when 'b' then 1 else 0 end) as 'b的个数',
sum(case StuName when 'c' then 1 else 0 end) as 'c的个数' from table
group by StuName
收获园豆：5
恩，试了一下，不对呀，还是显示3行，不过还是谢谢
select sum(case StuName when 'a' then 1 else 0 end) as 'a的个数',
sum(case StuName when 'b' then 1 else 0 end) as 'b的个数',
sum(case StuName when 'c' then 1 else 0 end) as 'c的个数' from Table_1
sum(case StuName when 'b' then 1 else 0 end) as 'b的个数',
sum(case StuName when 'c' then 1 else 0 end) as 'c的个数' from Table_1
这样可以了
@飒沓如流星:恩，好了，谢谢
其他回答(2)
0
select Count(*) from table group by stuname
不对呀，你的结果是这样的：
3
2
1
我需要在一行显示的
3
2
1
我需要在一行显示的
0
select max(num), avg(num), min(num)
from
(
select count(stuname) as num from student group by stuname
) as u
恩，谢谢
乱写这位
