查询归属统计的问题。。

[ideasky]

两个表，一个表存储问题，一个表存储答案，问题只有一条，答案可能对应有n条。
要查询出每个问题有多少个答案。

[Aslan_]

select 问题表.问题,isnull(count(答案表.答案ID),0) from 问题表 left join 答案表
on 问题表.问题ID =  答案表.问题ID

[pengxuan]

create table a (id int identity(1,1),question varchar(36))
go
create table b (id int identity(1,1),aid int,answer varchar(36))
go

insert into a 
select '中国的首都是哪个城市?' union all
select '你叫什么?'

insert into b
select 1,'上海' union all
select 1,'天津' union all
select 1,'深圳' union all
select 1,'北京' union all
select 2,'王五' union all
select 2,'张三' union all
select 2,'李四'

select * from a
select * from b

select a.question 问题,count(*) 答案数 from a inner join b on a.id=b.aid group by question

[让你望见影子的墙]

同意3楼的，使用左外连接。
select questionid,count(answser)
from questions left join answsers on questions.questionid=answsers.questionid
group by questions.questionid

[liangCK]

select a.questionid,count(b.answser) cnt
from questions a
  join answsers b
    on a.questionid=b.questionid
group by a.questionid

[viva369]

ls hao fast

[samson_www]

应该用外联结,因为可能有的问题没有答案
select a.questionid,isnull(b.answercount,0) as answer from questions a left join
(select count(1) as answercount from answers group by questionid) b
on a.questionid=b.questionid