你可以用 group by 与 sum(case when...) 如下所示：

select pq.Question, pq.PollID,
       sum(case when pr.Answer = 'A' then 1 else 0 end) as 'countA',
       sum(case when pr.Answer = 'B' then 1 else 0 end) as 'countB',
       sum(case when pr.Answer = 'C' then 1 else 0 end) as 'countC',
       sum(case when pr.Answer = 'D' then 1 else 0 end) as 'countD',
       sum(case when pr.Answer = 'E' then 1 else 0 end) as 'countE'
from PollQuestion pq
left join PollResponse pr on pq.PollID = pr.PollID
group by pq.Question, pq.PollID

您可以尝试使用条件聚合函数。

select 
    pollQuestions.Question, 
    pollQuestions.PollID, 
    count(CASE WHEN pollResponse.Answer ='A' THEN 1 END) countA,
    count(CASE WHEN pollResponse.Answer ='B' THEN 1 END) countB,
    count(CASE WHEN pollResponse.Answer ='C' THEN 1 END) countC,
    count(CASE WHEN pollResponse.Answer ='D' THEN 1 END) countD,
    count(CASE WHEN pollResponse.Answer ='E' THEN 1 END) countE
from pollQuestions 
JOIN pollResponse on pollQuestions.PollID = pollResponse.PollID  
group by 
    pollQuestions.Question,
    pollQuestions.PollID  
order by  
    pollResponse.PollID;

笔记
我会用 JOIN 而不是逗号 , 因为 JOIN 语法比 , 关于连接两个表。