SQL查询平均成绩
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共5个回答
热心网友
select
classid
as
班级编号,max(case
when
sex=0
then
avg_grade
else
0
end)
as
男生平均成绩,
max(case
when
sex=1
then
avg_grade
else
0
end)
as
女生平均成绩
from
(select
classid,sex,avg(grade)
as
avg_grade
from
student
a
inner
join
sc
b
on
a.id=b.id
)
t
group
by
classid
热心网友
主要思想是根据科目编号分组，然后求每组的最高分也就是各科成绩的最高分：
select CourseID,CourseName,MAX(Score)
from Score,Course
where Score.CourseID=Course.CourseID
group by CourseID
要求每组平均成绩将MAX(Score)换成AVG(Score)就行了
热心网友
select CourseName,max(Score) from Score join Course on Score .CourseID=Course.CourseID
group by CourseName
热心网友
select CourseID,CourseName,MAX(Score)
from Score,Course
where Score.CourseID=Course.CourseID
group by CourseID
热心网友
select CourseID,MAX(Score)
from Score,Course
where Score.CourseID=Course.CourseID
group by CourseID
