SQL:查找平均分数

给定这个表，我正在寻找一个查询来计算给定老师的给定问题的平均分数

如果我想在表中添加另一列，比如SCHOOLID，并希望有一列计算该学校给定问题的平均值，我会怎么做

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提前感谢您的帮助

您可以创建一个存储过程来处理整个需求

select teacherId, questionid, AVG(Score)
From myTable
group by teacherId, questionid

CREATE PROCEDURE avarageCalc
(
   @teacherid nvarchar(5) = null,
   @questionid int = null,
   @schoolid int = null
)
AS
Begin

    SELECT AVG(SCORE) as Avarage 
                   FROM Table 
                   WHERE (TeacherID = @teacherid OR @teacherid IS NULL) AND 
                         (QuestionId = @questionid OR @questionid IS NULL) AND
                         (SchoolId = @schoolid OR @schoolid IS NULL)

END

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您可以创建一个存储过程来处理整个需求

CREATE PROCEDURE avarageCalc
(
   @teacherid nvarchar(5) = null,
   @questionid int = null,
   @schoolid int = null
)
AS
Begin

    SELECT AVG(SCORE) as Avarage 
                   FROM Table 
                   WHERE (TeacherID = @teacherid OR @teacherid IS NULL) AND 
                         (QuestionId = @questionid OR @questionid IS NULL) AND
                         (SchoolId = @schoolid OR @schoolid IS NULL)

END

您可以这样做：

SELECT TeacherId, QuestionId, AVG(Score)
FROM TABLE-NAME
GROUP BY TeacherId, QuestionId

以下是一些有帮助的链接：

您可以这样做：

SELECT TeacherId, QuestionId, AVG(Score)
FROM TABLE-NAME
GROUP BY TeacherId, QuestionId

以下是一些有帮助的链接：

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知道了！我觉得这很简单。请将其插入表中，我可以运行如下更新语句：update TEST set AVGSCORE\u TEACHER=x.测试中的分数t join选择TEACHERID，questionid，score=AVGSCORE from TEST group by TEACHERID，t.TEACHERID=x.TEACHERID上的questionid x对于您的更新语句，您要将：和t.questionid=x.questionid添加到您的加入中。明白了！我觉得这很简单。请将其插入表中，我可以运行如下更新语句：update TEST set AVGSCORE\u TEACHER=x.测试中的分数t join选择TEACHERID，questionid，score=AVGSCORE from TEST group by TEACHERID，t.TEACHERID=x.TEACHERID上的questionid x对于更新语句，您要将：和t.questionid=x.questionid添加到您的加入中。