sql server 查询记录平均值及并列排在一条线序
的讲话查询学子的平分成绩并张开排行,sql
2002用子查询完结,分平均战绩再一次时保留排行空缺和不保留排名空缺二种。select
t1.* , px = (select count(1) from ( select m.S# [学子编号] , m.Sname
[学子姓名] , isnull(cast(avg(score) as decimal(18,2)),0) [平均成绩]
from Student m left join SC n on m.S# = n.S# group by m.S# , m.SnameState of Qatart2 where 平均战绩 t1.平分战表卡塔尔国 + 1 from ( select m.S# [学员编号] ,
m.Sname [学员姓名] , isnull(cast(avg(score) as decimal(18,2)),0)
[平均成绩] from Student m left join SC n on m.S# = n.S# group by
m.S# , m.Sname) t1order by px

叁个等级次序事关到的肆十多个Sql语句(整理版卡塔尔(قطر‎

/*标题:一个项目涉及到的50个Sql语句(整理版)说明:以下五十个语句都按照测试数据进行过测试,最好每次只单独运行一个语句。*/
--1.学生表
Student(S,Sname,Sage,Ssex) --S 学生编号,Sname 学生姓名,Sage 出生年月,Ssex 学生性别--2.课程表 
Course(C,Cname,T) --C --课程编号,Cname 课程名称,T 教师编号
--3.教师表 
Teacher(T,Tname) --T 教师编号,Tname 教师姓名--4.成绩表 
SC(S,C,score) --S 学生编号,C 课程编号,score 分数*/--创建测试数据
create table Student(S varchar(10),Sname nvarchar(10),Sage datetime,Ssex nvarchar(10))insert into Student values('01' , N'赵雷' , '1990-01-01' , N'男')insert into Student values('02' , N'钱电' , '1990-12-21' , N'男')insert into Student values('03' , N'孙风' , '1990-05-20' , N'男')insert into Student values('04' , N'李云' , '1990-08-06' , N'男')insert into Student values('05' , N'周梅' , '1991-12-01' , N'女')insert into Student values('06' , N'吴兰' , '1992-03-01' , N'女')insert into Student values('07' , N'郑竹' , '1989-07-01' , N'女')insert into Student values('08' , N'王菊' , '1990-01-20' , N'女')create table Course(C varchar(10),Cname nvarchar(10),T varchar(10))insert into Course values('01' , N'语文' , '02')insert into Course values('02' , N'数学' , '01')insert into Course values('03' , N'英语' , '03')create table Teacher(T varchar(10),Tname nvarchar(10))insert into Teacher values('01' , N'张三')insert into Teacher values('02' , N'李四')insert into Teacher values('03' , N'王五')create table SC(S varchar(10),C varchar(10),score decimal(18,1))insert into SC values('01' , '01' , 80)
insert into SC values('01' , '02' , 90)insert into SC values('01' , '03' , 99)
insert into SC values('02' , '01' , 70)insert into SC values('02' , '02' , 60)
insert into SC values('02' , '03' , 80)insert into SC values('03' , '01' , 80)
insert into SC values('03' , '02' , 80)insert into SC values('03' , '03' , 80)
insert into SC values('04' , '01' , 50)insert into SC values('04' , '02' , 30)
insert into SC values('04' , '03' , 20)insert into SC values('05' , '01' , 76)
insert into SC values('05' , '02' , 87)insert into SC values('06' , '01' , 31)
insert into SC values('06' , '03' , 34)insert into SC values('07' , '02' , 89)
insert into SC values('07' , '03' , 98)go

–1、查询”01″课程比”02″课程战表高的学生的音讯及学科分数
–1.1、查询同偶尔间设有”01″课程和”02″课程的状态
select a.* , b.score [课程’01’的分数],c.score [课程’02’的分数] from
Student a , SC b , SC c 
where a.S = b.S and a.S = c.S and b.C = ’01’ and c.C = ’02’ and b.score
> c.score
–1.2、查询同期存在”01″课程和”02″课程的气象和存在”01″课程但只怕子虚乌有”02″课程的景色(不设临时突显为null卡塔尔国(以下存在相仿内容时不再解释卡塔尔国
select a.* , b.score [课程”01″的分数],c.score [课程”02″的分数] from
Student a 
left join SC b on a.S = b.S and b.C = ’01’
left join SC c on a.S = c.S and c.C = ’02’
where b.score > isnull(c.score,0)

–2、查询”01″课程比”02″课程成绩低的学员的音讯及教程分数
–2.1、查询同不常候存在”01″课程和”02″课程的场地
select a.* , b.score [课程’01’的分数],c.score [课程’02’的分数] from
Student a , SC b , SC c 
where a.S = b.S and a.S = c.S and b.C = ’01’ and c.C = ’02’ and b.score
< c.score
–2.2、查询同期存在”01″课程和”02″课程的图景和不设有”01″课程但存在”02″课程的意况
select a.* , b.score [课程”01″的分数],c.score [课程”02″的分数] from
Student a 
left join SC b on a.S = b.S and b.C = ’01’
left join SC c on a.S = c.S and c.C = ’02’
where isnull(b.score,0) < c.score

–3、查询平均战表超越等于60分的同桌的上学的儿童编号和学员姓名和平均成绩
select a.S , a.Sname , cast(avg(b.score) as decimal(18,2)) avg_score
from Student a , sc b
where a.S = b.S
group by a.S , a.Sname
having cast(avg(b.score) as decimal(18,2)) >= 60 
order by a.S

–4、查询平均战绩小于60分的同班的学习者编号和学子姓名和平均战表
–4.1、查询在sc表存在成绩的学习者音讯的SQL语句。
select a.S , a.Sname , cast(avg(b.score) as decimal(18,2)) avg_score
from Student a , sc b
where a.S = b.S
group by a.S , a.Sname
having cast(avg(b.score) as decimal(18,2)) < 60 
order by a.S
–4.2、查询在sc表中子虚乌有战绩的学习者消息的SQL语句。
select a.S , a.Sname , isnull(cast(avg(b.score) as decimal(18,2)),0)
avg_score
from Student a left join sc b
on a.S = b.S
group by a.S , a.Sname
having isnull(cast(avg(b.score) as decimal(18,2)),0) < 60 
order by a.S

–5、查询全部同学的上学的小孩子编号、学子姓名、选课总的数量、全部课程的总战表
–5.1、查询全数有成就的SQL。
select a.S [学子编号], a.Sname [学子姓名], count(b.C卡塔尔 选课总量,
sum(scoreState of Qatar [负有科指标总成绩]
from Student a , SC b 
where a.S = b.S 
group by a.S,a.Sname 
order by a.S
–5.2、查询全体(包罗有实际业绩和无成绩卡塔尔(قطر‎的SQL。
select a.S [学子编号], a.Sname [学员姓名], count(b.C卡塔尔(قطر‎ 选课总量,
sum(scoreState of Qatar [富有科目标总战表]
from Student a left join SC b 
on a.S = b.S 
group by a.S,a.Sname 
order by a.S

–6、查询”李”姓老师的多寡 
–方法1
select count(Tname) [“李”姓老师的数量] from Teacher where Tname like
N’李%’
–方法2
select count(Tname) [“李”姓老师的数码] from Teacher where
left(Tname,1) = N’李’
/*
“李”姓老师的多寡   
———– 
1
*/

–7、查询学过”张三”老师讲授的同学的音信 
select distinct Student.* from Student , SC , Course , Teacher 
where Student.S = SC.S and SC.C = Course.C and Course.T = Teacher.T and
Teacher.Tname = N’张三’
order by Student.S

–8、查询没学过”张三”老师上课的同桌的新闻 
select m.* from Student m where S not in (select distinct SC.S from SC
, Course , Teacher where SC.C = Course.C and Course.T = Teacher.T and
Teacher.Tname = N’张三’) order by m.S

–9、查询学过数码为”01″並且也学过数码为”02″的课程的同窗的音信
–方法1
select Student.* from Student , SC where Student.S = SC.S and SC.C =
’01’ and exists (Select 1 from SC SC_2 where SC_2.S = SC.S and SC_2.C
= ’02’) order by Student.S
–方法2
select Student.* from Student , SC where Student.S = SC.S and SC.C =
’02’ and exists (Select 1 from SC SC_2 where SC_2.S = SC.S and SC_2.C
= ’01’) order by Student.S
–方法3
select m.* from Student m where S in
(
  select S from
  (
    select distinct S from SC where C = ’01’
    union all
    select distinct S from SC where C = ’02’
  ) t group by S having count(1) = 2 
)
order by m.S

–10、查询学过数码为”01″不过还没学过数码为”02″的课程的同室的信息
–方法1
select Student.* from Student , SC where Student.S = SC.S and SC.C =
’01’ and not exists (Select 1 from SC SC_2 where SC_2.S = SC.S and
SC_2.C = ’02’) order by Student.S
–方法2
select Student.* from Student , SC where Student.S = SC.S and SC.C =
’01’ and Student.S not in (Select SC_2.S from SC SC_2 where SC_2.S =
SC.S and SC_2.C = ’02’) order by Student.S

–11、查询未有学全全数科指标同班的音信 
–11.1、
select Student.*
from Student , SC 
where Student.S = SC.S 
group by Student.S , Student.Sname , Student.Sage , Student.Ssex having
count(C) < (select count(C) from Course) 
–11.2
select Student.*
from Student left join SC 
on Student.S = SC.S 
group by Student.S , Student.Sname , Student.Sage , Student.Ssex having
count(C) < (select count(C) from Course)

–12、查询至罕有一门课与学号为”01″的同室所学肖似的同室的音讯 
select distinct Student.* from Student , SC where Student.S = SC.S and
SC.C in (select C from SC where S = ’01’) and Student.S <> ’01’

–13、查询和”01″号的同班学习的课程完全相近的别的同学的音讯 
select Student.* from Student where S in
(select distinct SC.S from SC where S <> ’01’ and SC.C in (select
distinct C from SC where S = ’01’) 
group by SC.S having count(1) = (select count(1) from SC where S=’01’))

–14、查询没学过”张三”老师上课的任一门课程的上学的儿童姓名 
select student.* from student where student.S not in 
(select distinct sc.S from sc , course , teacher where sc.C = course.C
and course.T = teacher.T and teacher.tname = N’张三’)
order by student.S

–15、查询两门及其以上不如格课程的校友的学号,姓名及其平均战绩 
select student.S , student.sname , cast(avg(score) as decimal(18,2))
avg_score from student , sc 
where student.S = SC.S and student.S in (select S from SC where score
< 60 group by S having count(1) >= 2)
group by student.S , student.sname

–16、检索”01″课程分数小于60,按分数降序排列的上学的儿童音信
select student.* , sc.C , sc.score from student , sc 
where student.S = SC.S and sc.score < 60 and sc.C = ’01’
order by sc.score desc 

–17、按平均成绩从高到低突显全数学子的具有科目标战表以至平均战绩
–17.1 SQL 2000 静态 
select a.S 学子编号 , a.Sname 学子姓名 ,
       max(case c.Cname when N’语文’ then b.score else null end)
[语文],
       max(case c.Cname when N’数学’ then b.score else null end)
[数学],
       max(case c.Cname when N’英语’ then b.score else null end)
[英语],
       cast(avg(b.score) as decimal(18,2)) 平均分
from Student a 
left join SC b on a.S = b.S
left join Course c on b.C = c.C
group by a.S , a.Sname
order by 平均分 desc
–17.2 SQL 2000 动态 
declare @sql nvarchar(4000)
set @sql = ‘select a.S ‘ + N’学子编号’ + ‘ , a.Sname ‘ + N’学子姓名’
select @sql = @sql + ‘,max(case c.Cname when N”’+Cname+”’ then b.score
else null end) [‘+Cname+’]’
from (select distinct Cname from Course) as t
set @sql = @sql + ‘ , cast(avg(b.score) as decimal(18,2)) ‘ + N’平均分’

  • ‘ from Student a left join SC b on a.S = b.S left join Course c on b.C
    = c.C
    group by a.S , a.Sname order by ‘ + N’平均分’ + ‘ desc’
    exec(@sql)
    –17.3 有关sql 二〇〇五的动静态写法参见作者的稿子《普通行列转变(version
    2.0卡塔尔国》或《普通行列调换(version 3.0State of Qatar》。

 

对小编有用[9]丢个板砖[0]援引举报处理TOP 回复次数:1043

dawugui
(爱新觉罗.毓华卡塔尔
等 级:
3
更加的多勋章
#1楼 得分:0回复于:2010-05-17 17:47:07
SQL code
–18、查询各科战绩最高分、最低分和平均分:以如下情势呈现:课程ID,课程name,最高分,最低分,平均分,及格率,中等率,杰出率,卓绝率
–及格为>=60,中等为:70-80,优良为:80-90,优秀为:>=90
–方法1
select m.C [课程编号], m.Cname [课程名称], 
  max(n.score) [最高分],
  min(n.score) [最低分],
  cast(avg(n.score) as decimal(18,2)) [平均分],
  cast((select count(1) from SC where C = m.C and score >= 60)*100.0
/ (select count(1) from SC where C = m.C) as decimal(18,2))
[及格率(%)],
  cast((select count(1) from SC where C = m.C and score >= 70 and
score < 80 )*100.0 / (select count(1) from SC where C = m.C) as
decimal(18,2)) [中等率(%)],
  cast((select count(1) from SC where C = m.C and score >= 80 and
score < 90 )*100.0 / (select count(1) from SC where C = m.C) as
decimal(18,2)) [优良率(%)],
  cast((select count(1) from SC where C = m.C and score >= 90)*100.0
/ (select count(1) from SC where C = m.C) as decimal(18,2))
[优秀率(%)]
from Course m , SC n
where m.C = n.C
group by m.C , m.Cname
order by m.C
–方法2
select m.C [学科编号], m.Cname [课程名称], 
  (select max(score) from SC where C = m.C) [最高分],
  (select min(score) from SC where C = m.C) [最低分],
  (select cast(avg(score) as decimal(18,2)) from SC where C = m.C)
[平均分],
  cast((select count(1) from SC where C = m.C and score >= 60)*100.0
/ (select count(1) from SC where C = m.C) as decimal(18,2))
[及格率(%)],
  cast((select count(1) from SC where C = m.C and score >= 70 and
score < 80 )*100.0 / (select count(1) from SC where C = m.C) as
decimal(18,2)) [中等率(%)],
  cast((select count(1) from SC where C = m.C and score >= 80 and
score < 90 )*100.0 / (select count(1) from SC where C = m.C) as
decimal(18,2)) [优良率(%)],
  cast((select count(1) from SC where C = m.C and score >= 90)*100.0
/ (select count(1) from SC where C = m.C) as decimal(18,2))
[优秀率(%)]
from Course m 
order by m.C

–19、按各科成绩举办排序,并出示排行
–19.1 sql 二零零零用子查询完毕
–Score重复时保留排名空缺
select t.* , px = (select count(1) from SC where C = t.C and score >
t.score) + 1 from sc t order by t.C , px 
–Score重复时合併排行
select t.* , px = (select count(distinct score) from SC where C = t.C
and score >= t.score) from sc t order by t.C , px 
–19.2 sql 2005用rank,DENSE_RANK完成
–Score重复时保留排行空缺(rank完结卡塔尔国
select t.* , px = rank() over(partition by C order by score desc) from
sc t order by t.C , px 
–Score重复时合併排名(DENSE_RANK完成)
select t.* , px = DENSE_RANK() over(partition by C order by score
desc) from sc t order by t.C , px

–20、查询学生的总成绩并展开排名
–20.1 查询学子的总战表
select m.S [学子编号] , 
       m.Sname [学生姓名] ,
       isnull(sum(score),0) [总成绩]
from Student m left join SC n on m.S = n.S 
group by m.S , m.Sname
order by [总成绩] desc
–20.2 查询学生的总成绩并拓宽排行,sql
二零零一用子查询实现,分总分重复时保留排名空缺和不保留排行空缺三种。
select t1.* , px = (select count(1) from 
(
  select m.S [学子编号] , 
         m.Sname [学员姓名] ,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t2 where 总成绩 > t1.总成绩) + 1 from 
(
  select m.S [学员编号] , 
         m.Sname [学子姓名] ,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t1
order by px

select t1.* , px = (select count(distinct 总成绩) from 
(
  select m.S [学子编号] , 
         m.Sname [学子姓名] ,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t2 where 总成绩 >= t1.总成绩) from 
(
  select m.S [学员编号] , 
         m.Sname [学员姓名] ,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t1
order by px
–20.3 查询学子的总战表并张开排名,sql
2007用rank,DENSE_RANK实现,分总分重复时保留排行空缺和不保留排名空缺三种。
select t.* , px = rank() over(order by [总成绩] desc) from
(
  select m.S [学子编号] , 
         m.Sname [学子姓名] ,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t
order by px

select t.* , px = DENSE_RANK() over(order by [总成绩] desc) from
(
  select m.S [学子编号] , 
         m.Sname [学员姓名] ,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t
order by px

–21、查询分化老师所教分歧学科平均分从高到低展现 
select m.T , m.Tname , cast(avg(o.score) as decimal(18,2)) avg_score
from Teacher m , Course n , SC o
where m.T = n.T and n.C = o.C
group by m.T , m.Tname
order by avg_score desc

–22、查询全数科指标成就第2名到第3名的学员消息及该学科成绩
–22.1 sql 二〇〇一用子查询实现
–Score重复时保留排行空缺
select * from (select t.* , px = (select count(1) from SC where C =
t.C and score > t.score) + 1 from sc t) m where px between 2 and 3
order by m.C , m.px 
–Score重复时合併排名
select * from (select t.* , px = (select count(distinct score) from SC
where C = t.C and score >= t.score) from sc t) m where px between 2
and 3 order by m.C , m.px 
–22.2 sql 2005用rank,DENSE_RANK完成
–Score重复时保留排名空缺(rank完毕卡塔尔
select * from (select t.* , px = rank() over(partition by C order by
score desc) from sc t) m where px between 2 and 3 order by m.C , m.px 
–Score重复时合併排行(DENSE_RANK完成)
select * from (select t.* , px = DENSE_RANK() over(partition by C
order by score desc) from sc t) m where px between 2 and 3 order by m.C
, m.px

–23、总计各科成绩各分数段人数:课程编号,课程名称,[100-85],[85-70],[70-60],[0-60]及所占百分比 
–23.1
总计各科战绩各分数段人数:课程编号,课程名称,[100-85],[85-70],[70-60],[0-60]
–横向展现
select Course.C [课程编号] , Cname as [课程名称] ,
  sum(case when score >= 85 then 1 else 0 end) [85-100],
  sum(case when score >= 70 and score < 85 then 1 else 0 end)
[70-85],
  sum(case when score >= 60 and score < 70 then 1 else 0 end)
[60-70],
  sum(case when score < 60 then 1 else 0 end) [0-60]
from sc , Course 
where SC.C = Course.C 
group by Course.C , Course.Cname
order by Course.C
–纵向凸显1(展现存在的分数段卡塔尔(قطر‎
select m.C [学科编号] , m.Cname [课程名称] , 分数段 = (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end) , 
  count(1) 数量 
from Course m , sc n
where m.C = n.C 
group by m.C , m.Cname , (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end)
order by m.C , m.Cname , 分数段
–纵向显示2(展现存在的分数段,不设有的分数段用0展现卡塔尔(قطر‎
select m.C [课程编号] , m.Cname [课程名称] , 分数段 = (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end) , 
  count(1) 数量 
from Course m , sc n
where m.C = n.C 
group by all m.C , m.Cname , (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end)
order by m.C , m.Cname , 分数段

–23.2
总结各科战绩各分数段人数:课程编号,课程名称,[100-85],[85-70],[70-60],[<60]及所占百分比 
–横向显示
select m.C 课程编号, m.Cname 课程名称,
  (select count(1) from SC where C = m.C and score < 60) [0-60],
  cast((select count(1) from SC where C = m.C and score < 60)*100.0
/ (select count(1) from SC where C = m.C) as decimal(18,2))
[百分比(%)],
  (select count(1) from SC where C = m.C and score >= 60 and score
< 70) [60-70],
  cast((select count(1) from SC where C = m.C and score >= 60 and
score < 70)*100.0 / (select count(1) from SC where C = m.C) as
decimal(18,2)) [百分比(%)],
  (select count(1) from SC where C = m.C and score >= 70 and score
< 85) [70-85],
  cast((select count(1) from SC where C = m.C and score >= 70 and
score < 85)*100.0 / (select count(1) from SC where C = m.C) as
decimal(18,2)) [百分比(%)],
  (select count(1) from SC where C = m.C and score >= 85)
[85-100],
  cast((select count(1) from SC where C = m.C and score >= 85)*100.0
/ (select count(1) from SC where C = m.C) as decimal(18,2))
[百分比(%)]
from Course m 
order by m.C
–纵向显示1(呈现存在的分数段卡塔尔
select m.C [学科编号] , m.Cname [课程名称] , 分数段 = (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end) , 
  count(1) 数量 ,  
  cast(count(1) * 100.0 / (select count(1) from sc where C = m.C) as
decimal(18,2)) [百分比(%)]
from Course m , sc n
where m.C = n.C 
group by m.C , m.Cname , (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end)
order by m.C , m.Cname , 分数段
–纵向展现2(展现存在的分数段,空中楼阁的分数段用0展现卡塔尔国
select m.C [学科编号] , m.Cname [课程名称] , 分数段 = (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end) , 
  count(1) 数量 ,  
  cast(count(1) * 100.0 / (select count(1) from sc where C = m.C) as
decimal(18,2)) [百分比(%)]
from Course m , sc n
where m.C = n.C 
group by all m.C , m.Cname , (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end)
order by m.C , m.Cname , 分数段

 

对本人有用[6]丢个板砖[0]援引举报管理TOP
精髓推荐:SQL语句优化汇总

dawugui
(爱新觉罗.毓华卡塔尔
等 级:
3
更加的多勋章
#2楼 得分:0回复于:2010-05-17 17:47:22
SQL code
–24、查询学终身均战表及其排行 
–24.1 查询学子的平均成绩并展开排名,sql
二零零一用子查询实现,分平均战表再一次时保留排名空缺和不保留排名空缺二种。
select t1.* , px = (select count(1) from 
(
  select m.S [学子编号] , 
         m.Sname [学员姓名] ,
         isnull(cast(avg(score) as decimal(18,2)),0) [平均成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
State of Qatar t2 where 平均战表 > t1.平均成绩卡塔尔国 + 1 from 
(
  select m.S [学员编号] , 
         m.Sname [学生姓名] ,
         isnull(cast(avg(score) as decimal(18,2)),0) [平均战绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t1
order by px

select t1.* , px = (select count(distinct 平均战绩State of Qatar from 
(
  select m.S [学子编号] , 
         m.Sname [学生姓名] ,
         isnull(cast(avg(score) as decimal(18,2)),0) [平均战表]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
卡塔尔国 t2 where 平均战表 >= t1.平分成绩卡塔尔国 from 
(
  select m.S [学员编号] , 
         m.Sname [学员姓名] ,
         isnull(cast(avg(score) as decimal(18,2)),0) [平均战绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t1
order by px
–24.2 查询学子的平均成绩并拓宽排名,sql
2005用rank,DENSE_RANK完结,分平均战表再度时保留排行空缺和不保留排名空缺三种。
select t.* , px = rank() over(order by [平均成绩] desc) from
(
  select m.S [学员编号] , 
         m.Sname [学子姓名] ,
         isnull(cast(avg(score) as decimal(18,2)),0) [平均成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t
order by px

select t.* , px = DENSE_RANK() over(order by [平均战表] desc) from
(
  select m.S [学子编号] , 
         m.Sname [学子姓名] ,
         isnull(cast(avg(score) as decimal(18,2)),0) [平均成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t
order by px
  
–25、查询各科战绩前三名的笔录
–25.1 分数重复时保留排行空缺
select m.* , n.C , n.score from Student m, SC n where m.S = n.S and
n.score in 
(select top 3 score from sc where C = n.C order by score desc) order by
n.C , n.score desc
–25.2 分数重复时不保留排行空缺,归并排行
–sql 2001用子查询达成
select * from (select t.* , px = (select count(distinct score) from SC
where C = t.C and score >= t.score) from sc t) m where px between 1
and 3 order by m.C , m.px 
–sql 2005用DENSE_RANK实现
select * from (select t.* , px = DENSE_RANK() over(partition by C
order by score desc) from sc t) m where px between 1 and 3 order by m.C
, m.px

–26、查询每门学科被选修的上学的儿童数 
select C , count(S)[学生数] from sc group by C

–27、查询出独有两门学科的方方面面学生的学号和姓名 
select Student.S , Student.Sname
from Student , SC 
where Student.S = SC.S 
group by Student.S , Student.Sname
having count(SC.C) = 2
order by Student.S
 
–28、查询汉子、女子人数 
select count(Ssex卡塔尔(قطر‎ as 男人人数 from Student where Ssex = N’男’
select count(SsexState of Qatar as 女孩子人数 from Student where Ssex = N’女’
select sum(case when Ssex = N’男’ then 1 else 0 end)
[男人人数],sum(case when Ssex = N’女’ then 1 else 0 end) [女子人数]
from student
select case when Ssex = N’男’ then N’男子人数’ else N’女子人数’ end
[子女情事] , count(1) [人数] from student group by case when Ssex =
N’男’ then N’男士人数’ else N’女人人数’ end

–29、查询名字中隐含”风”字的上学的儿童音讯
select * from student where sname like N’%风%’
select * from student where charindex(N’风’ , sname) > 0

–30、查询同名同种性别学子名单,并计算同名家数 
select Sname [学员姓名], count(*) [人数] from Student group by
Sname having count(*) > 1
 
–31、查询一九九零年名落孙山的学子名单(注:Student表中Sage列的档期的顺序是datetime卡塔尔(قطر‎ 
select * from Student where year(sage) = 1990
select * from Student where datediff(yy,sage,’1990-01-01′) = 0
select * from Student where datepart(yy,sage) = 1990
select * from Student where convert(varchar(4),sage,120) = ‘1990’

–32、查询每门学科的平分战绩,结果按平均战绩降序排列,平均战表相像时,按学科编号升序排列 
select m.C , m.Cname , cast(avg(n.score) as decimal(18,2)) avg_score
from Course m, SC n 
where m.C = n.C    
group by m.C , m.Cname 
order by avg_score desc, m.C asc

–33、查询平均战绩超过等于85的全部学子的学号、姓名和平均战表 
select a.S , a.Sname , cast(avg(b.score) as decimal(18,2)) avg_score
from Student a , sc b
where a.S = b.S
group by a.S , a.Sname
having cast(avg(b.score) as decimal(18,2)) >= 85 
order by a.S

–34、查询课程名称叫”数学”,且分数低于60的上学的小孩子姓名和分数 
select sname , score
from Student , SC , Course 
where SC.S = Student.S and SC.C = Course.C and Course.Cname = N’数学’
and score < 60

–35、查询全体学员的教程及分数情状; 
select Student.* , Course.Cname , SC.C , SC.score  
from Student, SC , Course 
where Student.S = SC.S and SC.C = Course.C 
order by Student.S , SC.C

–36、查询别的一门课程战绩在70分以上的全名、课程名称和分数; 
select Student.* , Course.Cname , SC.C , SC.score  
from Student, SC , Course 
where Student.S = SC.S and SC.C = Course.C and SC.score >= 70 
order by Student.S , SC.C

–37、查询不如格的学科
select Student.* , Course.Cname , SC.C , SC.score  
from Student, SC , Course 
where Student.S = SC.S and SC.C = Course.C and SC.score < 60 
order by Student.S , SC.C

–38、查询课程编号为01且课程战表在80分以上的学子的学号和姓名; 
select Student.* , Course.Cname , SC.C , SC.score  
from Student, SC , Course 
where Student.S = SC.S and SC.C = Course.C and SC.C = ’01’ and SC.score
>= 80 
order by Student.S , SC.C

–39、求每门科目标学习者人数 
select Course.C , Course.Cname , count(*) [学员人数]
from Course , SC 
where Course.C = SC.C
group by  Course.C , Course.Cname
order by Course.C , Course.Cname

–40、查询选修”张三”老师所授课程的学员中,战绩最高的学员音讯及其成绩
–40.1 当最高分唯有贰个时
select top 1 Student.* , Course.Cname , SC.C , SC.score  
from Student, SC , Course , Teacher
where Student.S = SC.S and SC.C = Course.C and Course.T = Teacher.T and
Teacher.Tname = N’张三’
order by SC.score desc
–40.2 当最高分出现多少个时
select Student.* , Course.Cname , SC.C , SC.score  
from Student, SC , Course , Teacher
where Student.S = SC.S and SC.C = Course.C and Course.T = Teacher.T and
Teacher.Tname = N’张三’ and
SC.score = (select max(SC.score) from SC , Course , Teacher where SC.C =
Course.C and Course.T = Teacher.T and Teacher.Tname = N’张三’)

–41、查询区别学科成绩同样的学习者的学习者编号、课程编号、学子成绩 
–方法1
select m.* from SC m ,(select C , score from SC group by C , score
having count(1) > 1) n 
where m.C= n.C and m.score = n.score order by m.C , m.score , m.S
–方法2
select m.* from SC m where exists (select 1 from (select C , score from
SC group by C , score having count(1) > 1) n 
where m.C= n.C and m.score = n.score) order by m.C , m.score , m.S

–42、查询每门功成绩最佳的前两名 
select t.* from sc t where score in (select top 2 score from sc where C
= T.C order by score desc) order by t.C , t.score desc

–43、总计每门课程的学习者选修人数(超越5人的学科才总结)。必要输出课程号和选修人数,查询结果按人头降序排列,若人数相像,按学科号升序排列  
select Course.C , Course.Cname , count(*) [学员人数]
from Course , SC 
where Course.C = SC.C
group by  Course.C , Course.Cname
having count(*) >= 5
order by [学员人数] desc , Course.C

–44、检索起码选修两门学科的上学的儿童学号 
select student.S , student.Sname 
from student , SC 
where student.S = SC.S 
group by student.S , student.Sname 
having count(1) >= 2
order by student.S

–45、查询选修了任何学科的学员音讯 
–方法1 基于数据来变成
select student.* from student where S in
(select S from sc group by S having count(1) = (select count(1) from
course))
–方法2 用到重复否定来产生
select t.* from student t where t.S not in 
(
  select distinct m.S from
  (
    select S , C from student , course 
  ) m where not exists (select 1 from sc n where n.S = m.S and n.C =
m.C)
)
–方法3 应用重复否定来形成
select t.* from student t where not exists(select 1 from 
(
  select distinct m.S from
  (
    select S , C from student , course 
  ) m where not exists (select 1 from sc n where n.S = m.S and n.C =
m.C)
) k where k.S = t.S
)

–46、查询各学子的年华
–46.1 只遵照年度来算
select * , datediff(yy , sage , getdate()) [年龄] from student
–46.2 依照出生辰期来算,当前月日 < 出生年月的月日则,年龄减一
select * , case when right(convert(varchar(10),getdate(),120),5) <
right(convert(varchar(10),sage,120),5) then datediff(yy , sage ,
getdate()) – 1 else datediff(yy , sage , getdate()) end [年龄] from
student

–47、查询本周过华诞的学子
select * from student where datediff(week,datename(yy,getdate()) +
right(convert(varchar(10),sage,120),6),getdate()) = 0

–48、查询下一周过生日的学习者
select * from student where datediff(week,datename(yy,getdate()) +
right(convert(varchar(10),sage,120),6),getdate()) = -1

–49、查询前些时间过生辰的上学的小孩子
select * from student where datediff(mm,datename(yy,getdate()) +
right(convert(varchar(10),sage,120),6),getdate()) = 0

–50、查询前一个月过华诞的学子
select * from student where datediff(mm,datename(yy,getdate()) +
right(convert(varchar(10),sage,120),6),getdate()) = -1

drop table  Student,Course,Teacher,SC

–1.学生表
Student(S,Sname,Sage,SsexState of Qatar –S 学子编号,Sname 学子姓名,Sage
出生年月,Ssex 学子性别
–2.课程表 
Course(C,Cname,T卡塔尔(قطر‎ –C –课程编号,Cname 课程名称,T 教师编号
–3.教师表 
Teacher(T,Tname卡塔尔 –T 助教编号,Tname 教授姓名
–4.成绩表 
SC(S,C,score卡塔尔 –S 学子编号,C 课程编号,score 分数
*/
–创设测验数据
create table Student(S varchar(10),Sname nvarchar(10),Sage datetime,Ssex
nvarchar(10))
insert into Student values(’01’ , N’赵雷’ , ‘1990-01-01′ , N’男’)
insert into Student values(’02’ , N’钱电’ , ‘1990-12-21′ , N’男’)
insert into Student values(’03’ , N’孙风’ , ‘1990-05-20′ , N’男’)
insert into Student values(’04’ , N’李云’ , ‘1990-08-06′ , N’男’)
insert into Student values(’05’ , N’周梅’ , ‘1991-12-01′ , N’女’)
insert into Student values(’06’ , N’吴兰’ , ‘1992-03-01′ , N’女’)
insert into Student values(’07’ , N’郑竹’ , ‘1989-07-01′ , N’女’)
insert into Student values(’08’ , N’王菊’ , ‘1990-01-20′ , N’女’)
create table Course(C varchar(10),Cname nvarchar(10),T varchar(10))
insert into Course values(’01’ , N’语文’ , ’02’)
insert into Course values(’02’ , N’数学’ , ’01’)
insert into Course values(’03’ , N’英语’ , ’03’)
create table Teacher(T varchar(10),Tname nvarchar(10))
insert into Teacher values(’01’ , N’张三’)
insert into Teacher values(’02’ , N’李四’)
insert into Teacher values(’03’ , N’王五’)
create table SC(S varchar(10),C varchar(10),score decimal(18,1))
insert into SC values(’01’ , ’01’ , 80)
insert into SC values(’01’ , ’02’ , 90)
insert into SC values(’01’ , ’03’ , 99)
insert into SC values(’02’ , ’01’ , 70)
insert into SC values(’02’ , ’02’ , 60)
insert into SC values(’02’ , ’03’ , 80)
insert into SC values(’03’ , ’01’ , 80)
insert into SC values(’03’ , ’02’ , 80)
insert into SC values(’03’ , ’03’ , 80)
insert into SC values(’04’ , ’01’ , 50)
insert into SC values(’04’ , ’02’ , 30)
insert into SC values(’04’ , ’03’ , 20)
insert into SC values(’05’ , ’01’ , 76)
insert into SC values(’05’ , ’02’ , 87)
insert into SC values(’06’ , ’01’ , 31)
insert into SC values(’06’ , ’03’ , 34)
insert into SC values(’07’ , ’02’ , 89)
insert into SC values(’07’ , ’03’ , 98)
go

–1、查询”01″课程比”02″课程战绩高的学员的消息及教程分数
–1.1、查询同期存在”01″课程和”02″课程的场馆
select a.* , b.score [课程’01’的分数],c.score [课程’02’的分数] from
Student a , SC b , SC c 
where a.S = b.S and a.S = c.S and b.C = ’01’ and c.C = ’02’ and b.score
> c.score
–1.2、查询同有的时候间设有”01″课程和”02″课程的意况和存在”01″课程但大概不设有”02″课程的景况(空中楼阁时显示为null卡塔尔国(以下存在同样内容时不再解释卡塔尔国
select a.* , b.score [课程”01″的分数],c.score [课程”02″的分数] from
Student a 
left join SC b on a.S = b.S and b.C = ’01’
left join SC c on a.S = c.S and c.C = ’02’
where b.score > isnull(c.score,0)

–2、查询”01″课程比”02″课程战表低的上学的小孩子的音讯及学科分数
–2.1、查询同期设有”01″课程和”02″课程的景观
select a.* , b.score [课程’01’的分数],c.score [课程’02’的分数] from
Student a , SC b , SC c 
where a.S = b.S and a.S = c.S and b.C = ’01’ and c.C = ’02’ and b.score
< c.score
–2.2、查询同期设有”01″课程和”02″课程的景况和海市蜃楼”01″课程但存在”02″课程的事态
select a.* , b.score [课程”01″的分数],c.score [课程”02″的分数] from
Student a 
left join SC b on a.S = b.S and b.C = ’01’
left join SC c on a.S = c.S and c.C = ’02’
where isnull(b.score,0) < c.score

–3、查询平均成绩超越等于60分的同学的学子编号和学员姓名和平均战绩
select a.S , a.Sname , cast(avg(b.score) as decimal(18,2)) avg_score
from Student a , sc b
where a.S = b.S
group by a.S , a.Sname
having cast(avg(b.score) as decimal(18,2)) >= 60 
order by a.S

–4、查询平均成绩小于60分的同校的学员编号和学子姓名和平均成绩
–4.1、查询在sc表存在成绩的学员消息的SQL语句。
select a.S , a.Sname , cast(avg(b.score) as decimal(18,2)) avg_score
from Student a , sc b
where a.S = b.S
group by a.S , a.Sname
having cast(avg(b.score) as decimal(18,2)) < 60 
order by a.S
–4.2、查询在sc表中子虚乌有战表的学子音讯的SQL语句。
select a.S , a.Sname , isnull(cast(avg(b.score) as decimal(18,2)),0)
avg_score
from Student a left join sc b
on a.S = b.S
group by a.S , a.Sname
having isnull(cast(avg(b.score) as decimal(18,2)),0) < 60 
order by a.S

–5、查询全数同学的学子编号、学子姓名、选课总量、全数科指标总战表
–5.1、查询全部有成就的SQL。
select a.S [学生编号], a.Sname [学子姓名], count(b.CState of Qatar 选课总量,
sum(score卡塔尔国 [全部课程的总战表]
from Student a , SC b 
where a.S = b.S 
group by a.S,a.Sname 
order by a.S
–5.2、查询全部(富含有成就和无成绩卡塔尔(قطر‎的SQL。
select a.S [学子编号], a.Sname [学子姓名], count(b.C卡塔尔 选课总的数量,
sum(score卡塔尔(قطر‎ [不无课程的总成绩]
from Student a left join SC b 
on a.S = b.S 
group by a.S,a.Sname 
order by a.S

–6、查询”李”姓老师的数额 
–方法1
select count(Tname) [“李”姓老师的多寡] from Teacher where Tname like
N’李%’
–方法2
select count(Tname) [“李”姓老师的数量] from Teacher where
left(Tname,1) = N’李’
/*
“李”姓老师的数码   
———– 
1
*/

–7、查询学过”张三”老师教师的同校的新闻 
select distinct Student.* from Student , SC , Course , Teacher 
where Student.S = SC.S and SC.C = Course.C and Course.T = Teacher.T and
Teacher.Tname = N’张三’
order by Student.S

–8、查询没学过”张三”老师讲课的同班的新闻 
select m.* from Student m where S not in (select distinct SC.S from SC
, Course , Teacher where SC.C = Course.C and Course.T = Teacher.T and
Teacher.Tname = N’张三’) order by m.S

–9、查询学过数码为”01″并且也学过数码为”02″的科指标同室的新闻
–方法1
select Student.* from Student , SC where Student.S = SC.S and SC.C =
’01’ and exists (Select 1 from SC SC_2 where SC_2.S = SC.S and SC_2.C
= ’02’) order by Student.S
–方法2
select Student.* from Student , SC where Student.S = SC.S and SC.C =
’02’ and exists (Select 1 from SC SC_2 where SC_2.S = SC.S and SC_2.C
= ’01’) order by Student.S
–方法3
select m.* from Student m where S in
(
  select S from
  (
    select distinct S from SC where C = ’01’
    union all
    select distinct S from SC where C = ’02’
  ) t group by S having count(1) = 2 
)
order by m.S

–10、查询学过数码为”01″不过从未学过数码为”02″的科目标同桌的新闻
–方法1
select Student.* from Student , SC where Student.S = SC.S and SC.C =
’01’ and not exists (Select 1 from SC SC_2 where SC_2.S = SC.S and
SC_2.C = ’02’) order by Student.S
–方法2
select Student.* from Student , SC where Student.S = SC.S and SC.C =
’01’ and Student.S not in (Select SC_2.S from SC SC_2 where SC_2.S =
SC.S and SC_2.C = ’02’) order by Student.S

–11、查询未有学全全部课程的同学的音讯 
–11.1、
select Student.*
from Student , SC 
where Student.S = SC.S 
group by Student.S , Student.Sname , Student.Sage , Student.Ssex having
count(C) < (select count(C) from Course) 
–11.2
select Student.*
from Student left join SC 
on Student.S = SC.S 
group by Student.S , Student.Sname , Student.Sage , Student.Ssex having
count(C) < (select count(C) from Course)

–12、查询至罕见一门课与学号为”01″的同桌所学相像的同桌的音信 
select distinct Student.* from Student , SC where Student.S = SC.S and
SC.C in (select C from SC where S = ’01’) and Student.S <> ’01’

–13、查询和”01″号的同窗学习的科目完全相像的别的同学的新闻 
select Student.* from Student where S in
(select distinct SC.S from SC where S <> ’01’ and SC.C in (select
distinct C from SC where S = ’01’) 
group by SC.S having count(1) = (select count(1) from SC where S=’01’))

–14、查询没学过”张三”老师讲课的任一门科指标学员姓名 
select student.* from student where student.S not in 
(select distinct sc.S from sc , course , teacher where sc.C = course.C
and course.T = teacher.T and teacher.tname = N’张三’)
order by student.S

–15、查询两门及其以上不如格课程的同班的学号,姓名及其平均成绩 
select student.S , student.sname , cast(avg(score) as decimal(18,2))
avg_score from student , sc 
where student.S = SC.S and student.S in (select S from SC where score
< 60 group by S having count(1) >= 2)
group by student.S , student.sname

–16、检索”01″课程分数小于60,按分数降序排列的学子新闻
select student.* , sc.C , sc.score from student , sc 
where student.S = SC.S and sc.score < 60 and sc.C = ’01’
order by sc.score desc 

–17、按平均成绩从高到低展现全部学员的保有科目标战表以致平均战绩
–17.1 SQL 2000 静态 
select a.S 学子编号 , a.Sname 学子姓名 ,
       max(case c.Cname when N’语文’ then b.score else null end)
[语文],
       max(case c.Cname when N’数学’ then b.score else null end)
[数学],
       max(case c.Cname when N’英语’ then b.score else null end)
[英语],
       cast(avg(b.score) as decimal(18,2)) 平均分
from Student a 
left join SC b on a.S = b.S
left join Course c on b.C = c.C
group by a.S , a.Sname
order by 平均分 desc
–17.2 SQL 2000 动态 
declare @sql nvarchar(4000)
set @sql = ‘select a.S ‘ + N’学子编号’ + ‘ , a.Sname ‘ + N’学子姓名’
select @sql = @sql + ‘,max(case c.Cname when N”’+Cname+”’ then b.score
else null end) [‘+Cname+’]’
from (select distinct Cname from Course) as t
set @sql = @sql + ‘ , cast(avg(b.score) as decimal(18,2)) ‘ + N’平均分’

  • ‘ from Student a left join SC b on a.S = b.S left join Course c on b.C
    = c.C
    group by a.S , a.Sname order by ‘ + N’平均分’ + ‘ desc’
    exec(@sql)
    –17.3 有关sql 二〇〇六的动静态写法参见小编的稿子《普通行列转变(version
    2.0State of Qatar》或《普通行列转变(version 3.0卡塔尔国》。

 

对自个儿有用[9]丢个板砖[0]援引举报管理TOP 回复次数:1043

dawugui
(爱新觉罗.毓华卡塔尔
等 级:
3
更加多勋章
#1楼 得分:0回复于:2010-05-17 17:47:07
SQL code
–18、查询各科战表最高分、最低分和平均分:以如下格局显得:课程ID,课程name,最高分,最低分,平均分,及格率,中等率,特出率,优质率
–及格为>=60,中等为:70-80,优良为:80-90,优秀为:>=90
–方法1
select m.C [学科编号], m.Cname [课程名称], 
  max(n.score) [最高分],
  min(n.score) [最低分],
  cast(avg(n.score) as decimal(18,2)) [平均分],
  cast((select count(1) from SC where C = m.C and score >= 60)*100.0
/ (select count(1) from SC where C = m.C) as decimal(18,2))
[及格率(%)],
  cast((select count(1) from SC where C = m.C and score >= 70 and
score < 80 )*100.0 / (select count(1) from SC where C = m.C) as
decimal(18,2)) [中等率(%)],
  cast((select count(1) from SC where C = m.C and score >= 80 and
score < 90 )*100.0 / (select count(1) from SC where C = m.C) as
decimal(18,2)) [优良率(%)],
  cast((select count(1) from SC where C = m.C and score >= 90)*100.0
/ (select count(1) from SC where C = m.C) as decimal(18,2))
[优秀率(%)]
from Course m , SC n
where m.C = n.C
group by m.C , m.Cname
order by m.C
–方法2
select m.C [课程编号], m.Cname [课程名称], 
  (select max(score) from SC where C = m.C) [最高分],
  (select min(score) from SC where C = m.C) [最低分],
  (select cast(avg(score) as decimal(18,2)) from SC where C = m.C)
[平均分],
  cast((select count(1) from SC where C = m.C and score >= 60)*100.0
/ (select count(1) from SC where C = m.C) as decimal(18,2))
[及格率(%)],
  cast((select count(1) from SC where C = m.C and score >= 70 and
score < 80 )*100.0 / (select count(1) from SC where C = m.C) as
decimal(18,2)) [中等率(%)],
  cast((select count(1) from SC where C = m.C and score >= 80 and
score < 90 )*100.0 / (select count(1) from SC where C = m.C) as
decimal(18,2)) [优良率(%)],
  cast((select count(1) from SC where C = m.C and score >= 90)*100.0
/ (select count(1) from SC where C = m.C) as decimal(18,2))
[优秀率(%)]
from Course m 
order by m.C

–19、按各科成绩实行排序,并出示排名
–19.1 sql 2003用子查询实现
–Score重复时保留排名空缺
select t.* , px = (select count(1) from SC where C = t.C and score >
t.score) + 1 from sc t order by t.C , px 
–Score重复时合併排行
select t.* , px = (select count(distinct score) from SC where C = t.C
and score >= t.score) from sc t order by t.C , px 
–19.2 sql 2005用rank,DENSE_RANK完成
–Score重复时保留排名空缺(rank完毕卡塔尔(قطر‎
select t.* , px = rank() over(partition by C order by score desc) from
sc t order by t.C , px 
–Score重复时合併排行(DENSE_RANK完成)
select t.* , px = DENSE_RANK() over(partition by C order by score
desc) from sc t order by t.C , px

–20、查询学子的总战表并拓宽排名
–20.1 查询学子的总战绩
select m.S [学员编号] , 
       m.Sname [学员姓名] ,
       isnull(sum(score),0) [总成绩]
from Student m left join SC n on m.S = n.S 
group by m.S , m.Sname
order by [总成绩] desc
–20.2 查询学子的总战绩并举行排名,sql
2002用子查询实现,分总分重复时保留排行空缺和不保留排行空缺二种。
select t1.* , px = (select count(1) from 
(
  select m.S [学员编号] , 
         m.Sname [学子姓名] ,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t2 where 总成绩 > t1.总成绩) + 1 from 
(
  select m.S [学子编号] , 
         m.Sname [学子姓名] ,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t1
order by px

select t1.* , px = (select count(distinct 总成绩) from 
(
  select m.S [学员编号] , 
         m.Sname [学员姓名] ,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t2 where 总成绩 >= t1.总成绩) from 
(
  select m.S [学员编号] , 
         m.Sname [学子姓名] ,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t1
order by px
–20.3 查询学子的总成绩并扩充排行,sql
二〇〇五用rank,DENSE_RANK达成,分总分重复时保留名次空缺和不保留排行空缺两种。
select t.* , px = rank() over(order by [总成绩] desc) from
(
  select m.S [学子编号] , 
         m.Sname [学员姓名] ,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t
order by px

select t.* , px = DENSE_RANK() over(order by [总成绩] desc) from
(
  select m.S [学员编号] , 
         m.Sname [学员姓名] ,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t
order by px

–21、查询分化老师所教分裂学科平均分从高到低显示 
select m.T , m.Tname , cast(avg(o.score) as decimal(18,2)) avg_score
from Teacher m , Course n , SC o
where m.T = n.T and n.C = o.C
group by m.T , m.Tname
order by avg_score desc

–22、查询全体课程的成绩第2名到第3名的上学的小孩子新闻及该科目成绩
–22.1 sql 2001用子查询完结
–Score重复时保留排名空缺
select * from (select t.* , px = (select count(1) from SC where C =
t.C and score > t.score) + 1 from sc t) m where px between 2 and 3
order by m.C , m.px 
–Score重复时合併排行
select * from (select t.* , px = (select count(distinct score) from SC
where C = t.C and score >= t.score) from sc t) m where px between 2
and 3 order by m.C , m.px 
–22.2 sql 2005用rank,DENSE_RANK完成
–Score重复时保留排行空缺(rank完结卡塔尔国
select * from (select t.* , px = rank() over(partition by C order by
score desc) from sc t) m where px between 2 and 3 order by m.C , m.px 
–Score重复时归总名次(DENSE_RANK完成)
select * from (select t.* , px = DENSE_RANK() over(partition by C
order by score desc) from sc t) m where px between 2 and 3 order by m.C
, m.px

–23、总计各科战表各分数段人数:课程编号,课程名称,[100-85],[85-70],[70-60],[0-60]及所占百分比 
–23.1
总计各科战绩各分数段人数:课程编号,课程名称,[100-85],[85-70],[70-60],[0-60]
–横向展现
select Course.C [学科编号] , Cname as [课程名称] ,
  sum(case when score >= 85 then 1 else 0 end) [85-100],
  sum(case when score >= 70 and score < 85 then 1 else 0 end)
[70-85],
  sum(case when score >= 60 and score < 70 then 1 else 0 end)
[60-70],
  sum(case when score < 60 then 1 else 0 end) [0-60]
from sc , Course 
where SC.C = Course.C 
group by Course.C , Course.Cname
order by Course.C
–纵向显示1(显示存在的分数段卡塔尔国
select m.C [课程编号] , m.Cname [课程名称] , 分数段 = (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end) , 
  count(1) 数量 
from Course m , sc n
where m.C = n.C 
group by m.C , m.Cname , (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end)
order by m.C , m.Cname , 分数段
–纵向突显2(突显存在的分数段,空头支票的分数段用0呈现State of Qatar
select m.C [学科编号] , m.Cname [课程名称] , 分数段 = (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end) , 
  count(1) 数量 
from Course m , sc n
where m.C = n.C 
group by all m.C , m.Cname , (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end)
order by m.C , m.Cname , 分数段

–23.2
总结各科战绩各分数段人数:课程编号,课程名称,[100-85],[85-70],[70-60],[<60]及所占百分比 
–横向显示
select m.C 课程编号, m.Cname 课程名称,
  (select count(1) from SC where C = m.C and score < 60) [0-60],
  cast((select count(1) from SC where C = m.C and score < 60)*100.0
/ (select count(1) from SC where C = m.C) as decimal(18,2))
[百分比(%)],
  (select count(1) from SC where C = m.C and score >= 60 and score
< 70) [60-70],
  cast((select count(1) from SC where C = m.C and score >= 60 and
score < 70)*100.0 / (select count(1) from SC where C = m.C) as
decimal(18,2)) [百分比(%)],
  (select count(1) from SC where C = m.C and score >= 70 and score
< 85) [70-85],
  cast((select count(1) from SC where C = m.C and score >= 70 and
score < 85)*100.0 / (select count(1) from SC where C = m.C) as
decimal(18,2)) [百分比(%)],
  (select count(1) from SC where C = m.C and score >= 85)
[85-100],
  cast((select count(1) from SC where C = m.C and score >= 85)*100.0
/ (select count(1) from SC where C = m.C) as decimal(18,2))
[百分比(%)]
from Course m 
order by m.C
–纵向展现1(显示存在的分数段卡塔尔
select m.C [学科编号] , m.Cname [课程名称] , 分数段 = (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end) , 
  count(1) 数量 ,  
  cast(count(1) * 100.0 / (select count(1) from sc where C = m.C) as
decimal(18,2)) [百分比(%)]
from Course m , sc n
where m.C = n.C 
group by m.C , m.Cname , (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end)
order by m.C , m.Cname , 分数段
–纵向展现2(展现存在的分数段,不设有的分数段用0呈现卡塔尔国
select m.C [课程编号] , m.Cname [课程名称] , 分数段 = (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end) , 
  count(1) 数量 ,  
  cast(count(1) * 100.0 / (select count(1) from sc where C = m.C) as
decimal(18,2)) [百分比(%)]
from Course m , sc n
where m.C = n.C 
group by all m.C , m.Cname , (
  case when n.score >= 85 then ’85-100′
       when n.score >= 70 and n.score < 85 then ’70-85′
       when n.score >= 60 and n.score < 70 then ’60-70′
       else ‘0-60’
  end)
order by m.C , m.Cname , 分数段

 

对自小编有用[6]丢个板砖[0]援引举报管理TOP
精粹推荐:SQL语句优化汇总

dawugui
(爱新觉罗.毓华卡塔尔(قطر‎
等 级:
3
越多勋章
#2楼 得分:0回复于:2010-05-17 17:47:22
SQL code
–24、查询学一生均战绩及其排行 
–24.1 查询学子的平分成绩并打开排名,sql
二零零四用子查询实现,分平均战绩再一次时保留排名空缺和不保留排名空缺三种。
select t1.* , px = (select count(1) from 
(
  select m.S [学员编号] , 
         m.Sname [学员姓名] ,
         isnull(cast(avg(score) as decimal(18,2)),0) [平均成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
卡塔尔 t2 where 平均战绩 > t1.平分战绩卡塔尔(قطر‎ + 1 from 
(
  select m.S [学子编号] , 
         m.Sname [学员姓名] ,
         isnull(cast(avg(score) as decimal(18,2)),0) [平均战绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t1
order by px

select t1.* , px = (select count(distinct 平均战绩卡塔尔 from 
(
  select m.S [学子编号] , 
         m.Sname [学员姓名] ,
         isnull(cast(avg(score) as decimal(18,2)),0) [平均战绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t2 where 平均成绩 >= t1.等分成绩卡塔尔 from 
(
  select m.S [学子编号] , 
         m.Sname [学员姓名] ,
         isnull(cast(avg(score) as decimal(18,2)),0) [平均成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t1
order by px
–24.2 查询学子的平分战表并展开排名,sql
2007用rank,DENSE_RANK实现,分平均战绩再次时保留排行空缺和不保留排名空缺两种。
select t.* , px = rank() over(order by [平均战表] desc) from
(
  select m.S [学员编号] , 
         m.Sname [学员姓名] ,
         isnull(cast(avg(score) as decimal(18,2)),0) [平均成绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t
order by px

select t.* , px = DENSE_RANK() over(order by [平均成绩] desc) from
(
  select m.S [学子编号] , 
         m.Sname [学子姓名] ,
         isnull(cast(avg(score) as decimal(18,2)),0) [平均战绩]
  from Student m left join SC n on m.S = n.S 
  group by m.S , m.Sname
) t
order by px
  
–25、查询各科战表前三名的记录
–25.1 分数重复时保留排名空缺
select m.* , n.C , n.score from Student m, SC n where m.S = n.S and
n.score in 
(select top 3 score from sc where C = n.C order by score desc) order by
n.C , n.score desc
–25.2 分数重复时不保留排行空缺,归并排行
–sql 2001用子查询完成
select * from (select t.* , px = (select count(distinct score) from SC
where C = t.C and score >= t.score) from sc t) m where px between 1
and 3 order by m.C , m.px 
–sql 2005用DENSE_RANK实现
select * from (select t.* , px = DENSE_RANK() over(partition by C
order by score desc) from sc t) m where px between 1 and 3 order by m.C
, m.px

–26、查询每门学科被选修的学习者数 
select C , count(S)[学生数] from sc group by C

–27、查询出唯有两门学科的所有事学员的学号和姓名 
select Student.S , Student.Sname
from Student , SC 
where Student.S = SC.S 
group by Student.S , Student.Sname
having count(SC.C) = 2
order by Student.S
 
–28、查询男士、女孩子人数 
select count(Ssex卡塔尔 as 匹妻子数 from Student where Ssex = N’男’
select count(Ssex卡塔尔国 as 女孩子人数 from Student where Ssex = N’女’
select sum(case when Ssex = N’男’ then 1 else 0 end)
[男人人数],sum(case when Ssex = N’女’ then 1 else 0 end) [女孩子人数]
from student
select case when Ssex = N’男’ then N’男子人数’ else N’女人人数’ end
[孩子情事] , count(1) [人数] from student group by case when Ssex =
N’男’ then N’男子人数’ else N’女孩子人数’ end

–29、查询名字中富含”风”字的学员音讯
select * from student where sname like N’%风%’
select * from student where charindex(N’风’ , sname) > 0

–30、查询同名同种性别学子名单,并总计同有名气的人数 
select Sname [学子姓名], count(*) [人数] from Student group by
Sname having count(*) > 1
 
–31、查询1986年出生的学生名单(注:Student表中Sage列的项目是datetime卡塔尔(قطر‎ 
select * from Student where year(sage) = 1990
select * from Student where datediff(yy,sage,’1990-01-01′) = 0
select * from Student where datepart(yy,sage) = 1990
select * from Student where convert(varchar(4),sage,120) = ‘1990’

–32、查询每门学科的平均战绩,结果按平均战绩降序排列,平均战表同样时,按学科编号升序排列 
select m.C , m.Cname , cast(avg(n.score) as decimal(18,2)) avg_score
from Course m, SC n 
where m.C = n.C    
group by m.C , m.Cname 
order by avg_score desc, m.C asc

–33、查询平均战表超越等于85的具备学子的学号、姓名和平均战表 
select a.S , a.Sname , cast(avg(b.score) as decimal(18,2)) avg_score
from Student a , sc b
where a.S = b.S
group by a.S , a.Sname
having cast(avg(b.score) as decimal(18,2)) >= 85 
order by a.S

–34、查询课程名称叫”数学”,且分数低于60的学子姓名和分数 
select sname , score
from Student , SC , Course 
where SC.S = Student.S and SC.C = Course.C and Course.Cname = N’数学’
and score < 60

–35、查询全部学员的教程及分数情形; 
select Student.* , Course.Cname , SC.C , SC.score  
from Student, SC , Course 
where Student.S = SC.S and SC.C = Course.C 
order by Student.S , SC.C

–36、查询别的一门学科成绩在70分以上的姓名、课程名称和分数; 
select Student.* , Course.Cname , SC.C , SC.score  
from Student, SC , Course 
where Student.S = SC.S and SC.C = Course.C and SC.score >= 70 
order by Student.S , SC.C

–37、查询不比格的教程
select Student.* , Course.Cname , SC.C , SC.score  
from Student, SC , Course 
where Student.S = SC.S and SC.C = Course.C and SC.score < 60 
order by Student.S , SC.C

–38、查询课程编号为01且课程成绩在80分以上的学习者的学号和人名; 
select Student.* , Course.Cname , SC.C , SC.score  
from Student, SC , Course 
where Student.S = SC.S and SC.C = Course.C and SC.C = ’01’ and SC.score
>= 80 
order by Student.S , SC.C

–39、求每门课程的上学的小孩子人数 
select Course.C , Course.Cname , count(*) [学子人数]
from Course , SC 
where Course.C = SC.C
group by  Course.C , Course.Cname
order by Course.C , Course.Cname

–40、查询选修”张三”老师所授课程的学子中,成绩最高的学子音信及其成绩
–40.1 当最高分独有一个时
select top 1 Student.* , Course.Cname , SC.C , SC.score  
from Student, SC , Course , Teacher
where Student.S = SC.S and SC.C = Course.C and Course.T = Teacher.T and
Teacher.Tname = N’张三’
order by SC.score desc
–40.2 当最高分现身多个时
select Student.* , Course.Cname , SC.C , SC.score  
from Student, SC , Course , Teacher
where Student.S = SC.S and SC.C = Course.C and Course.T = Teacher.T and
Teacher.Tname = N’张三’ and
SC.score = (select max(SC.score) from SC , Course , Teacher where SC.C =
Course.C and Course.T = Teacher.T and Teacher.Tname = N’张三’)

–41、查询不相同科目战绩相似的上学的儿童的学童编号、课程编号、学子成绩 
–方法1
select m.* from SC m ,(select C , score from SC group by C , score
having count(1) > 1) n 
where m.C= n.C and m.score = n.score order by m.C , m.score , m.S
–方法2
select m.* from SC m where exists (select 1 from (select C , score from
SC group by C , score having count(1) > 1) n 
where m.C= n.C and m.score = n.score) order by m.C , m.score , m.S

–42、查询每门功战绩最佳的前两名 
select t.* from sc t where score in (select top 2 score from sc where C
= T.C order by score desc) order by t.C , t.score desc

–43、总计每门课程的上学的孩童选修人数(抢先5人的教程才总结)。须要输出课程号和选修人数,查询结果按人头降序排列,若人数雷同,按学科号升序排列  
select Course.C , Course.Cname , count(*) [学生人数]
from Course , SC 
where Course.C = SC.C
group by  Course.C , Course.Cname
having count(*) >= 5
order by [学员人数] desc , Course.C

–44、检索最少选修两门学科的学子学号 
select student.S , student.Sname 
from student , SC 
where student.S = SC.S 
group by student.S , student.Sname 
having count(1) >= 2
order by student.S

–45、查询选修了全体学科的学习者消息 
–方法1 依据数量来完毕
select student.* from student where S in
(select S from sc group by S having count(1) = (select count(1) from
course))
–方法2 用到重复否定来完成
select t.* from student t where t.S not in 
(
  select distinct m.S from
  (
    select S , C from student , course 
  ) m where not exists (select 1 from sc n where n.S = m.S and n.C =
m.C)
)
–方法3 利用重复否定来形成
select t.* from student t where not exists(select 1 from 
(
  select distinct m.S from
  (
    select S , C from student , course 
  ) m where not exists (select 1 from sc n where n.S = m.S and n.C =
m.C)
) k where k.S = t.S
)

–46、查询各学子的年龄
–46.1 只根据年度来算
select * , datediff(yy , sage , getdate()) [年龄] from student
–46.2 根据出出生之日期来算,当前月日 < 出生年月的月日则,年龄减一
select * , case when right(convert(varchar(10),getdate(),120),5) <
right(convert(varchar(10),sage,120),5) then datediff(yy , sage ,
getdate()) – 1 else datediff(yy , sage , getdate()) end [年龄] from
student

–47、查询本周过华诞的学习者
select * from student where datediff(week,datename(yy,getdate()) +
right(convert(varchar(10),sage,120),6),getdate()) = 0

–48、查询前一周过华诞的学员
select * from student where datediff(week,datename(yy,getdate()) +
right(convert(varchar(10),sage,120),6),getdate()) = -1

–49、查询前段日子过破壳日的学员
select * from student where datediff(mm,datename(yy,getdate()) +
right(convert(varchar(10),sage,120),6),getdate()) = 0

–50、查询前些日子过寿诞的学子
select * from student where datediff(mm,datename(yy,getdate()) +
right(convert(varchar(10),sage,120),6),getdate()) = -1

drop table  Student,Course,Teacher,SC

 

–4、查询平均成绩小于60分的同窗的学习者编号和学生姓名和平均成绩
–4.1、查询在sc表存在战绩的学子音讯的SQL语句。
select a.S# , a.Sname , cast(avg(b.score) as decimal(18,2)) avg_score
from Student a , sc b
where a.S# = b.S#
group by a.S# , a.Sname
having cast(avg(b.score) as decimal(18,2)) < 60
order by a.S#
–4.2、查询在sc表中不设有战绩的学习者消息的SQL语句。
select a.S# , a.Sname , isnull(cast(avg(b.score) as decimal(18,2)),0) avg_score
from Student a left join sc b
on a.S# = b.S#
group by a.S# , a.Sname
having isnull(cast(avg(b.score) as decimal(18,2)),0) < 60
order by a.S#

select t1.* , px = (select count(distinct 平均成绩卡塔尔(قطر‎ from ( select m.S#
[学员编号] , m.Sname [学员姓名] , isnull(cast(avg(score) as
decimal(18,2)),0) [平均成绩] from Student m left join SC n on m.S# =
n.S# group by m.S# , m.Sname卡塔尔国 t2 where 平均成绩 = t1.等分战表State of Qatar from (
select m.S# [学生编号] , m.Sname [学员姓名] ,
isnull(cast(avg(score) as decimal(18,2)),0) [平均战表] from Student m
left join SC n on m.S# = n.S# group by m.S# , m.Sname) t1order by px

青云

 随笔 – 2, 文章 – 0, 评论 – 1, 引用 – 0

–6、查询”李”姓老师的数码

–1.学生表Student(S#,Sname,Sage,Ssex) –S# 学子编号,Sname
学子姓名,Sage 出生年月,Ssex 学子性别–2.课程表 Course(C#,Cname,T#)
–C# –课程编号,Cname 课程名称,T# 教授编号–3.教授表
Teacher(T#,Tname) –T# 教授编号,Tname 教师姓名–4.成就表
SC(S#,C#,score) –S# 学子编号,C# 课程编号,score 分数

“李”姓老师的多寡  

1
*/

–7、查询学过”张三”老师讲课的同窗的音信
select distinct Student.* from Student , SC , Course ,
Teacher
where Student.S# = SC.S# and SC.C# = Course.C# and Course.T# = Teacher.T# and Teacher.Tname = N’张三’
order by Student.S#

–8、查询没学过”张三”老师教师的同桌的新闻
select m.* from Student m where S# not in (select distinct SC.S# from SC , Course , Teacher
where SC.C# = Course.C# and Course.T# = Teacher.T# and Teacher.Tname = N’张三’) order by m.S#

–9、查询学过数码为”01″并且也学过数码为”02″的学科的同班的音讯
–方法1
select Student.* from Student , SC where Student.S# = SC.S# and SC.C# = ’01’ and exists (Select 1 from SC SC_2 where SC_2.S# = SC.S# and SC_2.C# = ’02’) order by Student.S#
–方法2
select Student.* from Student , SC where Student.S# = SC.S# and SC.C# = ’02’ and exists (Select 1 from SC SC_2 where SC_2.S# = SC.S# and SC_2.C# = ’01’) order by Student.S#
–方法3
select m.* from Student m where S# in
(
  select S# from
  (
    select distinct S# from SC where C# =
’01’
    union all
    select distinct S# from SC where C# =
’02’
  ) t group by
S# having count(1)
= 2
)
order by m.S#

–10、查询学过数码为”01″可是未有学过数码为”02″的科指标同学的音讯
–方法1
select Student.* from Student , SC where Student.S# = SC.S# and SC.C# = ’01’ and not exists (Select 1 from SC SC_2 where SC_2.S# = SC.S# and SC_2.C# = ’02’) order by Student.S#
–方法2
select Student.* from Student , SC where Student.S# = SC.S# and SC.C# = ’01’ and Student.S# not in (Select SC_2.S# from SC SC_2 where SC_2.S# = SC.S# and SC_2.C# = ’02’) order by Student.S#

–11、查询没有学全全部科目标校友的音信
–11.1、
select Student.*
from Student , SC
where Student.S# = SC.S#
group by Student.S# , Student.Sname ,
Student.Sage , Student.Ssex having count(C#) < (select count(C#) from Course)
–11.2
select Student.*
from Student left join SC
on Student.S# = SC.S#
group by Student.S# , Student.Sname ,
Student.Sage , Student.Ssex having count(C#) < (select count(C#) from Course)

–12、查询至少有一门课与学号为”01″的同学所学相仿的同窗的音讯

select distinct Student.* from Student , SC where Student.S# = SC.S# and SC.C# in (select C# from SC where S# = ’01’) and Student.S# <> ’01’

–13、查询和”01″号的同桌学习的学科完全肖似的别的同学的音信

select Student.* from Student where S# in
(select distinct SC.S# from SC where S# <> ’01’ and SC.C# in (select distinct C# from SC where S# = ’01’)
group by SC.S# having count(1) = (select count(1) from SC where S#=’01’))

–14、查询没学过”张三”老师教学的任一门科目标学员姓名

select student.* from student where student.S# not in
(select distinct sc.S# from sc , course , teacher
where sc.C# = course.C# and course.T# = teacher.T# and teacher.tname = N’张三’)
order by student.S#

–15、查询两门及其以上比不上格课程的同校的学号,姓名及其平均战绩

select student.S# , student.sname ,
cast(avg(score) as decimal(18,2)) avg_score from student , sc
where student.S# = SC.S# and student.S# in (select S# from SC where score < 60
group by S# having count(1) >= 2)
group by student.S# , student.sname

–16、检索”01″课程分数小于60,按分数降序排列的学员新闻
select student.* , sc.C# , sc.score
from student , sc
where student.S# = SC.S# and sc.score < 60
and sc.C# = ’01’
order by sc.score desc 

–17、按平均成绩从高到低显示全数学员的富有课程的大成以致平均战绩
–17.1 SQL 2000
静态
select a.S# 学子编号 , a.Sname
学子姓名 ,
       max(case c.Cname when N’语文’
then b.score else null end) [语文],
       max(case c.Cname when N’数学’
then b.score else null end) [数学],
       max(case c.Cname when N’英语’
then b.score else null end) [英语],
       cast(avg(b.score) as
decimal(18,2)) 平均分
from Student a
left join SC b on a.S# = b.S#
left join Course c on b.C# = c.C#
group by a.S# , a.Sname
order by 平均分 desc
–17.2 SQL 2000 动态
declare @sql nvarchar(4000)
set @sql = ‘select a.S# ‘ + N’学子编号’ + ‘ , a.Sname ‘ + N’学子姓名’
select @sql = @sql + ‘,max(case c.Cname when
N”’+Cname+”’ then b.score else null end)
[‘+Cname+’]’
from (select distinct Cname from Course) as t
set @sql = @sql + ‘ , cast(avg(b.score) as
decimal(18,2)) ‘

  • N’平均分’ + ‘ from Student a left join SC b
    on a.S# = b.S# left join Course c on b.C# = c.C#
    group by a.S# , a.Sname order by ‘
  • N’平均分’ + ‘ desc’
    exec(@sql)
    –17.3 有关sql
    二〇〇七的动静态写法参见小编的篇章《普通行列转变(version
    2.0State of Qatar》或《普通行列调换(version 3.0卡塔尔国》。

–18、查询各科战表最高分、最低分和平均分:以如下格局显得:课程ID,课程name,最高分,最低分,平均分,及格率,中等率,优异率,特出率
–及格为>=60,中等为:70-80,优良为:80-90,优秀为:>=90
–方法1
select m.C# [学科编号], m.Cname [课程名称],
  max(n.score) [最高分],
  min(n.score) [最低分],
  cast(avg(n.score) as decimal(18,2)) [平均分],
  cast((select count(1) from SC where C# = m.C# and score >= 60)*100.0 /
(select count(1) from SC where C# = m.C#) as decimal(18,2)) [及格率(%)],
  cast((select count(1) from SC where C# = m.C# and score >= 70
and score < 80
)*100.0 /
(select count(1) from SC where C# = m.C#) as decimal(18,2)) [中等率(%)],
  cast((select count(1) from SC where C# = m.C# and score >= 80
and score < 90
)*100.0 /
(select count(1) from SC where C# = m.C#) as decimal(18,2)) [优良率(%)],
  cast((select count(1) from SC where C# = m.C# and score >= 90)*100.0 /
(select count(1) from SC where C# = m.C#) as decimal(18,2)) [优秀率(%)]
from Course m , SC n
where m.C# = n.C#
group by m.C# , m.Cname
order by m.C#
–方法2
select m.C# [课程编号], m.Cname [课程名称],
  (select max(score) from SC where C# =
m.C#) [最高分],
  (select min(score) from SC where C# =
m.C#) [最低分],
  (select cast(avg(score) as
decimal(18,2)) from SC where C# =
m.C#) [平均分],
  cast((select count(1) from SC where C# = m.C# and score >= 60)*100.0 /
(select count(1) from SC where C# = m.C#) as decimal(18,2)) [及格率(%)],
  cast((select count(1) from SC where C# = m.C# and score >= 70
and score < 80
)*100.0 /
(select count(1) from SC where C# = m.C#) as decimal(18,2)) [中等率(%)],
  cast((select count(1) from SC where C# = m.C# and score >= 80
and score < 90
)*100.0 /
(select count(1) from SC where C# = m.C#) as decimal(18,2)) [优良率(%)],
  cast((select count(1) from SC where C# = m.C# and score >= 90)*100.0 /
(select count(1) from SC where C# = m.C#) as decimal(18,2)) [优秀率(%)]
from Course m
order by m.C#

–19、按各科战绩进行排序,并展现排行
–19.1 sql
二零零零用子查询完毕
–Score重复时保留排名空缺
select t.* , px = (select count(1) from SC where C# = t.C# and score > t.score) + 1 from sc t order by t.c# , px
–Score重复时合并排名
select t.* , px = (select count(distinct score) from SC where C# = t.C# and score >= t.score) from sc t order by t.c# , px
–19.2 sql
2005用rank,DENSE_RANK完成
–Score重复时保留排名空缺(rank达成State of Qatar
select t.* , px = rank() over(partition by c# order by score desc) from sc t order by t.C# , px
–Score重复时合并排名(DENSE_RANK完成)
select t.* , px = DENSE_RANK() over(partition by c# order by score desc) from sc t order by t.C# , px

–20、查询学子的总成绩并扩充排行
–20.1
查询学子的总战绩
select m.S# [学员编号] ,
       m.Sname [学员姓名]
,
       isnull(sum(score),0) [总成绩]
from Student m left join SC n on m.S# = n.S#
group by m.S# , m.Sname
order by [总成绩] desc
–20.2
查询学子的总战表并进行排行,sql
二〇〇二用子查询完成,分总分重复时保留排行空缺和不保留排名空缺三种。
select t1.* , px = (select count(1) from
(
  select m.S# [学员编号]
,
         m.Sname [学员姓名]
,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S# = n.S#
  group by m.S# , m.Sname
) t2 where 总成绩 > t1.总成绩) +
1
from
(
  select m.S# [学子编号]
,
         m.Sname [学子姓名]
,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S# = n.S#
  group by m.S# , m.Sname
) t1
order by px

select t1.* , px = (select count(distinct 总成绩) from
(
  select m.S# [学员编号]
,
         m.Sname [学员姓名]
,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S# = n.S#
  group by m.S# , m.Sname
) t2 where 总成绩 >= t1.总成绩) from
(
  select m.S# [学员编号]
,
         m.Sname [学生姓名]
,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S# = n.S#
  group by m.S# , m.Sname
) t1
order by px
–20.3
查询学子的总成绩并扩充排行,sql
二〇〇五用rank,DENSE_RANK实现,分总分重复时保留排名空缺和不保留排行空缺两种。
select t.* , px = rank() over(order by [总成绩] desc) from
(
  select m.S# [学子编号]
,
         m.Sname [学员姓名]
,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S# = n.S#
  group by m.S# , m.Sname
) t
order by px

select t.* , px = DENSE_RANK() over(order by [总成绩] desc) from
(
  select m.S# [学员编号]
,
         m.Sname [学子姓名]
,
         isnull(sum(score),0) [总成绩]
  from Student m left join SC n on m.S# = n.S#
  group by m.S# , m.Sname
) t
order by px

–21、查询分裂老师所教分化科目平均分从高到低展现

select m.T# , m.Tname , cast(avg(o.score) as decimal(18,2)) avg_score
from Teacher m , Course n , SC o
where m.T# = n.T# and n.C# = o.C#
group by m.T# , m.Tname
order by avg_score desc

–22、查询全数课程的大成第2名到第3名的上学的小孩子音讯及该科目战绩
–22.1 sql
2004用子查询完毕
–Score重复时保留排名空缺
select * from (select t.* , px = (select count(1) from SC where C# = t.C# and score > t.score) + 1 from sc t) m where px between 2 and 3 order by m.c# , m.px
–Score重复时归并排名
select * from (select t.* , px = (select count(distinct score) from SC where C# = t.C# and score >= t.score) from sc t) m where px between 2 and 3 order by m.c# , m.px
–22.2 sql
2005用rank,DENSE_RANK完成
–Score重复时保留排名空缺(rank完毕卡塔尔
select * from (select t.* , px = rank() over(partition by c# order by score desc) from sc t) m where px between 2 and 3 order by m.C# , m.px
–Score重复时归总排行(DENSE_RANK完成)
select * from (select t.* , px = DENSE_RANK() over(partition by c# order by score desc) from sc t) m where px between 2 and 3 order by m.C# , m.px

–23、计算各科成绩各分数段人数:课程编号,课程名称,[100-85],[85-70],[70-60],[0-60]及所占比例

–23.1
计算各科成绩各分数段人数:课程编号,课程名称,[100-85],[85-70],[70-60],[0-60]
–横向展现
select Course.C# [学科编号] , Cname as [课程名称] ,
  sum(case when score >= 85
then 1 else 0 end) [85-100],
  sum(case when score >= 70
and score < 85
then 1 else 0 end) [70-85],
  sum(case when score >= 60
and score < 70
then 1 else 0 end) [60-70],
  sum(case when score < 60
then 1 else 0 end) [0-60]
from sc , Course
where SC.C# = Course.C#
group by Course.C# , Course.Cname
order by Course.C#
–纵向呈现1(展现存在的分数段卡塔尔(قطر‎
select m.C# [课程编号] , m.Cname [课程名称] , 分数段 = (
  case when n.score >= 85
then ’85-100′
       when n.score >= 70
and n.score < 85
then ’70-85′
       when n.score >= 60
and n.score < 70
then ’60-70′
       else ‘0-60’
  end) ,
  count(1) 数量
from Course m , sc n
where m.C# = n.C#
group by m.C# , m.Cname , (
  case when n.score >= 85
then ’85-100′
       when n.score >= 70
and n.score < 85
then ’70-85′
       when n.score >= 60
and n.score < 70
then ’60-70′
       else ‘0-60’
  end)
order by m.C# , m.Cname , 分数段
–纵向展现2(呈现存在的分数段,海市蜃楼的分数段用0展现卡塔尔
select m.C# [学科编号] , m.Cname [课程名称] , 分数段 = (
  case when n.score >= 85
then ’85-100′
       when n.score >= 70
and n.score < 85
then ’70-85′
       when n.score >= 60
and n.score < 70
then ’60-70′
       else ‘0-60’
  end) ,
  count(1) 数量
from Course m , sc n
where m.C# = n.C#
group by all m.C# , m.Cname , (
  case when n.score >= 85
then ’85-100′
       when n.score >= 70
and n.score < 85
then ’70-85′
       when n.score >= 60
and n.score < 70
then ’60-70′
       else ‘0-60’
  end)
order by m.C# , m.Cname , 分数段

–23.2
总括各科战表各分数段人数:课程编号,课程名称,[100-85],[85-70],[70-60],[<60]及所占比重

–横向显示
select m.C# 课程编号, m.Cname
课程名称,
  (select count(1)
from SC where C# = m.C# and score < 60) [0-60],
  cast((select count(1) from SC where C# = m.C# and score < 60)*100.0 /
(select count(1) from SC where C# = m.C#) as decimal(18,2)) [百分比(%)],
  (select count(1)
from SC where C# = m.C# and score >= 60
and score < 70) [60-70],
  cast((select count(1) from SC where C# = m.C# and score >= 60
and score < 70)*100.0 /
(select count(1) from SC where C# = m.C#) as decimal(18,2)) [百分比(%)],
  (select count(1)
from SC where C# = m.C# and score >= 70
and score < 85) [70-85],
  cast((select count(1) from SC where C# = m.C# and score >= 70
and score < 85)*100.0 /
(select count(1) from SC where C# = m.C#) as decimal(18,2)) [百分比(%)],
  (select count(1)
from SC where C# = m.C# and score >= 85) [85-100],
  cast((select count(1) from SC where C# = m.C# and score >= 85)*100.0 /
(select count(1) from SC where C# = m.C#) as decimal(18,2)) [百分比(%)]
from Course m
order by m.C#
–纵向展现1(展现存在的分数段State of Qatar
select m.C# [学科编号] , m.Cname [课程名称] , 分数段 = (
  case when n.score >= 85
then ’85-100′
       when n.score >= 70
and n.score < 85
then ’70-85′
       when n.score >= 60
and n.score < 70
then ’60-70′
       else ‘0-60’
  end) ,
  count(1) 数量 , 
  cast(count(1) * 100.0 /
(select count(1) from sc where C# = m.C#) as decimal(18,2)) [百分比(%)]
from Course m , sc n
where m.C# = n.C#
group by m.C# , m.Cname , (
  case when n.score >= 85
then ’85-100′
       when n.score >= 70
and n.score < 85
then ’70-85′
       when n.score >= 60
and n.score < 70
then ’60-70′
       else ‘0-60’
  end)
order by m.C# , m.Cname , 分数段
–纵向展现2(显示存在的分数段,不设有的分数段用0展现卡塔尔国
select m.C# [课程编号] , m.Cname [课程名称] , 分数段 = (
  case when n.score >= 85
then ’85-100′
       when n.score >= 70
and n.score < 85
then ’70-85′
       when n.score >= 60
and n.score < 70
then ’60-70′
       else ‘0-60’
  end) ,
  count(1) 数量 , 
  cast(count(1) * 100.0 /
(select count(1) from sc where C# = m.C#) as decimal(18,2)) [百分比(%)]
from Course m , sc n
where m.C# = n.C#
group by all m.C# , m.Cname , (
  case when n.score >= 85
then ’85-100′
       when n.score >= 70
and n.score < 85
then ’70-85′
       when n.score >= 60
and n.score < 70
then ’60-70′
       else ‘0-60’
  end)
order by m.C# , m.Cname , 分数段

–24、查询学毕生均战表及其名次

–24.1
查询学生的平分成绩并拓宽排名,sql
2004用子查询达成,分平均成绩再一次时保留排名空缺和不保留排名空缺二种。
select t1.* , px = (select count(1) from
(
  select m.S# [学员编号]
,
         m.Sname [学员姓名]
,
         isnull(cast(avg(score) as
decimal(18,2)),0) [平均成绩]
  from Student m left join SC n on m.S# = n.S#
  group by m.S# , m.Sname
卡塔尔 t2 where 平均战绩 > t1.等分成绩卡塔尔国 +
1
from
(
  select m.S# [学子编号]
,
         m.Sname [学员姓名]
,
         isnull(cast(avg(score) as
decimal(18,2)),0) [平均战表]
  from Student m left join SC n on m.S# = n.S#
  group by m.S# , m.Sname
) t1
order by px

select t1.* , px = (select count(distinct 平均战绩卡塔尔国 from
(
  select m.S# [学子编号]
,
         m.Sname [学员姓名]
,
         isnull(cast(avg(score) as
decimal(18,2)),0) [平均战表]
  from Student m left join SC n on m.S# = n.S#
  group by m.S# , m.Sname
卡塔尔国 t2 where 平均成绩 >= t1.平分成绩卡塔尔 from
(
  select m.S# [学生编号]
,
         m.Sname [学子姓名]
,
         isnull(cast(avg(score) as
decimal(18,2)),0) [平均战表]
  from Student m left join SC n on m.S# = n.S#
  group by m.S# , m.Sname
) t1
order by px
–24.2
查询学子的平分成绩并扩充排行,sql
2005用rank,DENSE_RANK实现,分平均成绩再一次时保留排名空缺和不保留排行空缺二种。
select t.* , px = rank() over(order by [平均战表] desc) from
(
  select m.S# [学员编号]
,
         m.Sname [学员姓名]
,
         isnull(cast(avg(score) as
decimal(18,2)),0) [平均战表]
  from Student m left join SC n on m.S# = n.S#
  group by m.S# , m.Sname
) t
order by px

select t.* , px = DENSE_RANK() over(order by [平均战表] desc) from
(
  select m.S# [学子编号]
,
         m.Sname [学子姓名]
,
         isnull(cast(avg(score) as
decimal(18,2)),0) [平均成绩]
  from Student m left join SC n on m.S# = n.S#
  group by m.S# , m.Sname
) t
order by px
 
–25、查询各科成绩前三名的记录
–25.1
分数重复时保留排行空缺
select m.* , n.C# , n.score from Student m, SC n where m.S# = n.S# and n.score in
(select top 3 score from sc where C# = n.C# order by score desc) order by n.C# , n.score desc
–25.2
分数重复时不保留排行空缺,合併排行
–sql
贰零零壹用子查询达成
select * from (select t.* , px = (select count(distinct score) from SC where C# = t.C# and score >= t.score) from sc t) m where px between 1 and 3 order by m.c# , m.px
–sql
2005用DENSE_RANK实现
select * from (select t.* , px = DENSE_RANK() over(partition by c# order by score desc) from sc t) m where px between 1 and 3 order by m.C# , m.px

–26、查询每门科目被选修的学习者数

select c# , count(S#)[学生数] from sc group by C#

–27、查询出独有两门课程的一切上学的儿童的学号和人名

select Student.S# , Student.Sname
from Student , SC
where Student.S# = SC.S#
group by Student.S# , Student.Sname
having count(SC.C#) = 2
order by Student.S#

–28、查询男生、女子人数

select count(Ssex卡塔尔 as 男人人数 from Student where Ssex = N’男’
select count(Ssex卡塔尔国 as 女孩子人数 from Student where Ssex = N’女’
select sum(case when Ssex = N’男’ then 1 else 0 end) [汉子人数],sum(case when Ssex = N’女’ then 1 else 0 end) [女孩子人数] from student
select case when Ssex = N’男’ then N’男子人数’ else N’女子人数’ end [男女情事] , count(1) [人数] from student group by case when Ssex = N’男’ then N’男士人数’ else N’女孩子人数’ end

–29、查询名字中带有”风”字的上学的小孩子消息
select * from student where sname like N’%风%’
select * from student where charindex(N’风’ , sname) > 0

–30、查询同名同种性别学子名单,并计算同有名的人数
select Sname [学员姓名], count(*) [人数] from Student group by Sname having count(*) > 1

–31、查询1988年降生的学子名单(注:Student表中Sage列的门类是datetime卡塔尔(قطر‎

select * from Student where year(sage) = 1990
select * from Student where datediff(yy,sage,’1990-01-01′) = 0
select * from Student where datepart(yy,sage) = 1990
select * from Student where convert(varchar(4),sage,120) =
‘1990’

–32、查询每门课程的平分成绩,结果按平均成绩降序排列,平均战绩同样时,按学科编号升序排列

select m.C# , m.Cname , cast(avg(n.score) as decimal(18,2)) avg_score
from Course m, SC n
where m.C# = n.C#   
group by m.C# , m.Cname
order by avg_score desc, m.C# asc

–33、查询平均战表超乎等于85的有所学子的学号、姓名和平均战绩

select a.S# , a.Sname , cast(avg(b.score) as decimal(18,2)) avg_score
from Student a , sc b
where a.S# = b.S#
group by a.S# , a.Sname
having cast(avg(b.score) as decimal(18,2)) >= 85
order by a.S#

–34、查询课程名叫”数学”,且分数低于60的学员姓名和分数

select sname , score
from Student , SC , Course
where SC.S# = Student.S# and SC.C# = Course.C# and Course.Cname = N’数学’ and score < 60

–35、查询全体学子的学科及分数景况;
select Student.* , Course.Cname , SC.C# ,
SC.score 
from Student, SC , Course
where Student.S# = SC.S# and SC.C# = Course.C#
order by Student.S# , SC.C#

–36、查询任何一门科目成绩在70分以上的姓名、课程名称和分数;

select Student.* , Course.Cname , SC.C# ,
SC.score 
from Student, SC , Course
where Student.S# = SC.S# and SC.C# = Course.C# and SC.score >= 70
order by Student.S# , SC.C#

–37、查询不比格的教程
select Student.* , Course.Cname , SC.C# ,
SC.score 
from Student, SC , Course
where Student.S# = SC.S# and SC.C# = Course.C# and SC.score < 60
order by Student.S# , SC.C#

–38、查询课程编号为01且课程成绩在80分以上的学习者的学号和人名;

select Student.* , Course.Cname , SC.C# ,
SC.score 
from Student, SC , Course
where Student.S# = SC.S# and SC.C# = Course.C# and SC.C# = ’01’ and SC.score >= 80
order by Student.S# , SC.C#

–39、求每门学科的上学的小孩子人数

select Course.C# , Course.Cname ,
count(*) [学生人数]
from Course , SC
where Course.C# = SC.C#
group by  Course.C# , Course.Cname
order by Course.C# , Course.Cname

–40、查询选修”张三”老师所授课程的学生中,成绩最高的学子消息及其战绩
–40.1
当最高分唯有三个时
select top 1 Student.* , Course.Cname , SC.C# ,
SC.score 
from Student, SC , Course ,
Teacher
where Student.S# = SC.S# and SC.C# = Course.C# and Course.T# = Teacher.T# and Teacher.Tname = N’张三’
order by SC.score desc
–40.2
当最高分现身多少个时
select Student.* , Course.Cname , SC.C# ,
SC.score 
from Student, SC , Course ,
Teacher
where Student.S# = SC.S# and SC.C# = Course.C# and Course.T# = Teacher.T# and Teacher.Tname = N’张三’ and
SC.score =
(select max(SC.score) from SC , Course , Teacher
where SC.C# = Course.C# and Course.T# = Teacher.T# and Teacher.Tname = N’张三’)

–41、查询区别科目战表相通的上学的儿童的上学的儿童编号、课程编号、学子战表

–方法1
select m.* from SC m ,(select C# , score from SC group by C# , score having count(1) > 1) n
where m.C#= n.C# and m.score = n.score order by m.C# , m.score , m.S#
–方法2
select m.* from SC m where exists (select 1 from (select C# , score from SC group by C# , score having count(1) > 1) n
where m.C#= n.C# and m.score = n.score) order by m.C# , m.score , m.S#

–42、查询每门功战表最棒的前两名

select t.* from sc t where score in (select top 2 score from sc where C# = T.C# order by score desc) order by t.C# , t.score desc

–43、总计每门课程的学童选修人数(抢先5人的教程才总计)。须要输出课程号和选修人数,查询结果按人头降序排列,若人数相同,按学科号升序排列 

select Course.C# , Course.Cname ,
count(*) [学子人数]
from Course , SC
where Course.C# = SC.C#
group by  Course.C# , Course.Cname
having count(*) >= 5
order by [学子人数] desc , Course.C#

–44、检索最少选修两门学科的学习者学号
select student.S# , student.Sname
from student , SC
where student.S# = SC.S#
group by student.S# , student.Sname
having count(1) >= 2
order by student.S#

–45、查询选修了全体学科的学童新闻

–方法1
遵照数量来完结
select student.* from student where S# in
(select S# from sc group by S# having count(1) = (select count(1) from course))
–方法2
使用重复否定来实现
select t.* from student t where t.S# not in
(
  select distinct m.S# from
  (
    select S# , C# from student , course
  ) m where not exists (select 1
from sc n where n.S# = m.S# and n.C# = m.C#)
)
–方法3
利用重复否定来完毕
select t.* from student t where not exists(select 1 from
(
  select distinct m.S# from
  (
    select S# , C# from student , course
  ) m where not exists (select 1
from sc n where n.S# = m.S# and n.C# = m.C#)
) k where k.S# =
t.S#
)

–46、查询各学子的年龄
–46.1
只依据年度来算
select * , datediff(yy , sage , getdate()) [年龄] from student
–46.2 根据出出生之日期来算,当前月日
< 出生年月的月日则,年龄减一
select * , case when right(convert(varchar(10),getdate(),120),5) < right(convert(varchar(10),sage,120),5) then datediff(yy , sage , getdate()) – 1 else datediff(yy , sage , getdate()) end [年龄] from student

–47、查询本周过破壳日的学员
select * from student where datediff(week,datename(yy,getdate()) + right(convert(varchar(10),sage,120),6),getdate()) = 0

–48、查询前一周过出生之日的学子
select * from student where datediff(week,datename(yy,getdate()) + right(convert(varchar(10),sage,120),6),getdate()) = -1

–49、查询上月过出生之日的学习者
select * from student where datediff(mm,datename(yy,getdate()) + right(convert(varchar(10),sage,120),6),getdate()) = 0

–50、查询后一个月过破壳日的学员
select * from student where datediff(mm,datename(yy,getdate()) + right(convert(varchar(10),sage,120),6),getdate()) = -1

drop table 
Student,Course,Teacher,SC

Author

发表评论

电子邮件地址不会被公开。 必填项已用*标注