Question

我有两个查询给出两组结果，我想将一个查询的结果除以另一个。

这是我的第一个问题：

SELECT COUNT(*) 
FROM survey_event_answers a JOIN survey_events e ON a.eventid = e.eventid
WHERE e.event_status = 'Closed' AND 
      e.survey_date BETWEEN '2013-05-01' AND '2014-01-31' AND 
      a.response_options IN (10,11) AND a.questionid = 7 
GROUP BY MONTH(e.survey_date) DESC;

以下是此查询的结果：

这是我的另一个疑问：

SELECT COUNT(*),e.survey_date 
FROM `survey_event_answers` a INNER JOIN survey_events e ON a.eventid = e.eventid
WHERE e.event_status='Closed' AND 
      e.survey_date BETWEEN '2013-05-01' AND '2014-01-31' AND 
      a.questionid=7 
GROUP BY MONTH(e.survey_date) DESC

以下是查询结果：

我希望第一行结果集的第一行除以第二行第一行。

请帮助我如何做到这一点。

由于

Answer 1

这是你在寻找什么？

SELECT rd1.r1/rd2.r2 `result`
FROM (
    SELECT COUNT(*) r1,MONTH(e.survey_date) d1
    FROM `survey_event_answers` a 
    INNER JOIN survey_events e 
    ON (a.eventid = e.eventid) 
    WHERE e.event_status='Closed' AND e.survey_date BETWEEN '2013-05-01' AND '2014-01-31'
    AND a.response_options IN (10,11) AND a.questionid=7 
    GROUP BY MONTH(e.survey_date) DESC ) rd1
 JOIN (
    SELECT COUNT(*) r2, MONTH(e.survey_date) d2 
    FROM `survey_event_answers` a 
    INNER JOIN survey_events e 
    ON (a.eventid = e.eventid) 
    WHERE e.event_status='Closed' AND e.survey_date BETWEEN '2013-05-01' AND '2014-01-31'
    AND a.questionid=7 
    GROUP BY MONTH(e.survey_date) DESC ) rd2
  ON rd1.d1=rd2.d2

Answer 2

你可以这样做：

  SELECT SUM(IF(a.response_options IN (10,11), 1, 0))/COUNT(*) 
    FROM survey_event_answers a 
    JOIN survey_events e 
      ON a.eventid = e.eventid
   WHERE e.event_status = 'Closed' 
     AND e.survey_date BETWEEN '2013-05-01' AND '2014-01-31' 
     AND a.questionid = 7 
 GROUP BY MONTH(e.survey_date) DESC;

这可能不会很快（但它比执行两次查询并加入结果更快），但可能会做你想要的（答案10或11的比例）。您可以将MONTH(e.survey_date)添加为第二列。

将具有多个记录的查询结果与在mysql中具有多个记录的另一个查询结果分开

2 个答案: