寻找没有孩子的一对多父母

Question

假设我有下面两张表，我如何找到没有（0）个答案的所有问题？

question 
--------- 
id 
content 

和

answer 
------ 
id 
question_id 
content 

即question 1->* answers

- 编辑 -

要添加到我的问题，我将如何检索每个问题的答案计数？

Answer 1

select * from question q where not exists (select 1 from answer a where a.question_id=q.id) 

回答编辑的问题：

select q.id, content, count(a.id) 
    from question q 
    left outer join answer a 
    on q.id = a.question_id 
group by q.id 

Answer 2

你可以找到用低于查询。

Select * from question where id not in (Select question_id from answer)