我有3个表，即Question，Feedback和FeedbackResult。我希望生成一份报告，在其中我需要找到每个问题的平均评分。
Questions
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QuestionId Question
1 Question 1
2 Question 2
3 Question 3
4 Question 4
5 Question 5
Feedback
--------
FeedbackId Questions QuestionCount
2 1,2,3,4,5 5 -- Questions column has questionid from Question table
FeedbackResults
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FeedbackResId FeedbackId Answers
1 2 4,3,5,2,3 -- these answers are ratings(1 to 5) against each question
2 2 4,2,3,4,5 -- which means 4 is the rating for QuestionId 1, 2 is for QuestionId 2 etc
3 2 5,3,4,3,2
4 2 4,1,1,1,2
我希望得到每个问题的平均评分结果
Question Rating
Question 1 3.5
Question 2 4
Question 3 5
Question 4 2
Question 5 4.5
修改
我应该将数据库表重新设计为
FeedbackResults
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FeedbackResId FeedbackId QuetionID Answers UserId
1 2 4 4 1
2 2 1 3 1
3 2 5 3 1
4 2 1 2 2