java⾯试题sql_SQL⾯试题⽬及答案java⾯试题
学⽣成绩表(stuscore)：
姓名：name    课程：subject    分数：score    学号：stuid
张三    数学    89    1
张三    语⽂    80    1
张三    英语    70    1
李四    数学    90    2
李四    语⽂    70    2
李四    英语    80    2
1.计算每个⼈的总成绩并排名(要求显⽰字段：姓名，总成绩)
答案：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(要求显⽰字段: 学号，姓名，总成绩)
答案：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(要求显⽰字段: 学号，姓名，课程，最⾼成绩)
答案：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(要求显⽰字段: 学号，姓名，平均成绩)
答案：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(要求显⽰字段: 学号，姓名，科⽬，成绩)
答案：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(要求显⽰字段: 学号，姓名，科⽬，成绩)
答案：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.统计如下：学号    姓名    语⽂    数学    英语    总分    平均分
答案：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(要求显⽰字段：课程，平均成绩)
答案：select subject,avg(score) as avgscore from stuscoregroup by subject
9．列出数学成绩的排名(要求显⽰字段：学号，姓名，成绩，排名)
答案：
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 score desc
declare @id int
set @id=0;
update @tmp set @id=@id+1,pm=@id
select * from @tmp
oracle:
select  DENSE_RANK () OVER(order by score desc) as row,name,subject,score,stuid from stuscore where subject=’数
学’order by score desc
ms sql(最佳选择)sql查询面试题及答案
select (select count(*) from stuscore t1 where subject =’数学’ and t1.score>t2.score)+1 as row ,stuid,name,score from stuscore t2 where subject =’数学’ order by score desc
10．列出数学成绩在2-3名的学⽣(要求显⽰字段：学号，姓名，科⽬，成绩)
答案：select t3.*  from(select top 2 t2.*  from (select top 3 name,subject,score,stuid from stuscore where subject=’数
学’order by score desc) t2 order by t2.score) t3 order by t3.score desc
11．求出李四的数学成绩的排名
答案：
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 score descdeclare @id intset @id=0;update @tmp set @id=@id+1,pm=@idselect * from
@tmp where name=’李四’
12．统计如下：课程    不及格(0-59)个    良(60-80)个    优(81-100)个
答案：select subject, (select count(*) from stuscore where score<60 and subject=t1.subject) as 不及格,(select count(*) from stuscore where score between 60 and 80 and subject=t1.subject) as 良,(select count(*) from stuscore where score >80 and subject=t1.subject) as 优from stuscore t1 group by subject
13．统计如下：数学：张三(50分)，李四(90分)，王五(90分)，赵六(76分)
答案：
declare @s varchar(1000)set @s=”select @s =@s+’,’+name+'(‘+convert(varchar(10),score)+’分)’ from stuscore where subject=’数学’ set @s=stuff(@s,1,1,”)print ‘数学:’+@s
14.计算科科及格的⼈的平均成绩
答案： select distinct t1.stuid,t2.avgscore  from stuscore t1,(select stuid,avg(score) as avgscore from stuscore  group by stuid  ) t2,(select stuid from stuscore where score<60 group by stuid) t3 where t1.stuid=t2.stuid and t1.stuid!=t3.stuid;
select  name,avg(score) as avgscore  from stuscore s  where (select sum(case when i.score>=60 then 1 else 0 end) from stuscore i where  i.name= s.name)=3  group by name