查询选择已回答每个问题的答案集中的所有问题的用户

Question

这是mysql表。

  User Question Answer 
      20  1   answer1_2 
      20  2   answer2_5 
      20  3   answer3_1 
      726  1   answer1_2 
      726  2   answer2_5 
      726  3   answer3_1 

我想谁给的所有问题的答案， 的用户，我们有组预定义的每个问题的答案。

喜欢问1可以从答案answer1_1，answer1_2，answer1_3 问题2可具有answer2_1，answer2_2，answer2_3

答案起初，我想这样的查询：

  SELECT GROUP_CONCAT(DISTINCT CAST(User AS CHAR)) allUsers, COUNT(DISTINCT User) totalUsers 
      FROM survey 
      WHERE 
      (
       (
       Question =1 
       AND Answer = 'answer1_2' 
       ) 
       OR (
       Question =1 
       AND Answer = 'answer1_2' 
       ) 
       OR (
       Question =1 
       AND Answer = 'answer1_3' 
       ) 
      ) 
      AND (
       (
       Question =2 
       AND Answer = 'answer2_1' 
       ) 
       OR (
       Question =2 
       AND Answer = 'answer2_2' 
       ) 
       OR (
       Question =2 
       AND Answer = 'answer2_3' 
       ) 
      ) 

后来我看到结果，并意识到所有问题中的“AND”不适用于我的要求 ，但我需要结果与该逻辑。

表结构无法更改。

Answer 1

你可以这样做：

Select user, count(answer) from survey group by user having count(answer)=3 

Answer 2

如果您对领域User和Question唯一的密钥，那么你可以做这样的事情：

SELECT count(Question) answers_no, .... FROM survey GROUP BY User HAVING answers_no = num_total_questions 

你可以通过num_total_questions作为从应用程序变量