SQL统计大全收藏版 个人使用
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1.计算每个人的总成绩并排名
select name,sum(score) as allscore from stuscore group by name order by allscore
2.计算每个人的总成绩并排名
select distinct t1.name,t1.stuid,t2.allscore from stuscore t1,( select stuid,sum(score) as allscore from stuscore group by stuid)t2where t1.stuid=t2.stuidorder by t2.allscore desc
3. 计算每个人单科的最高成绩
select t1.stuid,t1.name,t1.subject,t1.score from stuscore t1,(select stuid,max(score) as maxscore from stuscore group by stuid) t2where t1.stuid=t2.stuid and t1.score=t2.maxscore
4.计算每个人的平均成绩
select distinct t1.stuid,t1.name,t2.avgscore from stuscore t1,(select stuid,avg(score) as avgscore from stuscore group by stuid) t2where t1.stuid=t2.stuid
5.列出各门课程成绩最好的学生
select t1.stuid,t1.name,t1.subject,t2.maxscore from stuscore t1,(select subject,max(score) as maxscore from stuscore group by subject) t2where t1.subject=t2.subject and t1.score=t2.maxscore
6.列出各门课程成绩最好的两位学生
select distinct t1.* from stuscore t1 where t1.id in (select top 2 stuscore.id from stuscore where subject = t1.subject order by score desc) order by t1.subject
7.学号 姓名 语文 数学 英语 总分 平均分
select stuid as 学号,name as 姓名,sum(case when subject='语文' then score else 0 end) as 语文,sum(case when subject='数学' then score else 0 end) as 数学,sum(case when subject='英语' then score else 0 end) as 英语,sum(score) as 总分,(sum(score)/count(*)) as 平均分from stuscoregroup by stuid,name order by 总分desc
8.列出各门课程的平均成绩
select subject,avg(score) as avgscore from stuscoregroup by subject
9.列出数学成绩的排名
declare @tmp table(pm int,name varchar(50),score int,stuid int)insert into @tmp select null,name,score,stuid from stuscore where subject='数学' order by sc
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