Question

我正在创建一个存储过程，通过计算每个选项的投票来查看民意调查答案的结果，但是当我运行它时，每个select语句都在单个表中，但我希望结果在单个表中，而每个select语句都是一栏，任何人都知道如何做到这一点。谢谢：）多数民众赞成我的代码：

CREATE PROC view_pollresult
 @myemail VARCHAR (30),
 @course_ID INT,
 @poll_ID INT 
 AS
 IF @myemail = (SELECT page_creator FROM Course_pages WHERE course_ID = @course_ID OR @myemail IN (SELECT added_email
 FROM Lecturers_Adds_Academics_Course_page WHERE course_ID = @course_ID))
 BEGIN
 SELECT COUNT(choice) FROM Students_Answers_Polls AS choice1_results
 WHERE poll_ID = @poll_ID AND course_page = @course_ID
 AND choice = (SELECT choice1 FROM Polls WHERE poll_ID = @poll_ID) 
 SELECT COUNT(choice) FROM Students_Answers_Polls AS choice2_results
 WHERE poll_ID = @poll_ID AND course_page = @course_ID
 AND choice = (SELECT choice2 FROM Polls WHERE poll_ID = @poll_ID) 
 SELECT COUNT(choice) FROM Students_Answers_Polls AS choice3_results
 WHERE poll_ID = @poll_ID AND course_page = @course_ID
 AND choice = (SELECT choice3 FROM Polls WHERE poll_ID = @poll_ID) 
 SELECT COUNT(choice) FROM Students_Answers_Polls AS choice4_results
 WHERE poll_ID = @poll_ID AND course_page = @course_ID
 AND choice = (SELECT choice4 FROM Polls WHERE poll_ID = @poll_ID) 
 SELECT COUNT(choice) FROM Students_Answers_Polls AS choice5_results
 WHERE poll_ID = @poll_ID AND course_page = @course_ID
 AND choice = (SELECT choice5 FROM Polls WHERE poll_ID = @poll_ID) 
 END

Answer 1

只需将其作为一个声明：

SELECT 
    SUM(case when results.choice = p.choice1 then 1 else 0 end) as Choice1Count,
    SUM(case when results.choice = p.choice2 then 1 else 0 end) as Choice2Count,
    SUM(case when results.choice = p.choice3 then 1 else 0 end) as Choice3Count,
    SUM(case when results.choice = p.choice4 then 1 else 0 end) as Choice4Count,
    SUM(case when results.choice = p.choice5 then 1 else 0 end) as Choice5Count
FROM 
    Students_Answers_Polls AS results
    inner join Polls p on
        results.poll_id = p.poll_id
        and results.choice in (p.choice1, p.choice2, p.choice3, p.choice4, p.choice5)
WHERE 
    results.poll_ID = @poll_ID 
    AND course_page = @course_ID

Answer 2

您需要做的是创建一个连接所有表的select语句，并仅将您需要的列返回到一个表中。尝试这样的事情：

select count(a.choice) as choice1_results, count(b.choice) as choice2_results
from students_answers_polls a
inner join students_ansers_polls b on a.couseId = b.courseId
and a.poll = (select choice1 from polls where poll_Id = @poll_ID)
and b.poll = (select choice2 from polls where poll_id = @poll_ID)

等等......

如何将多个select语句组合到一个表中

2 个答案: