sql语句多表查询(学生表/课程表/教师表/成绩表 )
sql语句多表查询(学生表/课程表/教师表/成绩表 )
问题及描述：--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' , '' , N'男')insert into Student values('02' , N'钱电' , '' , N'男')insert into Student values('03' , N'孙风' , '' , N'男')insert into Student values('04' , N'李云' , '' , N'男')insert into Student values('05' , N'周梅' , '' , N'女')insert into Student values('06' , N'吴兰' , '' , N'女')insert into Student values('07' , N'郑竹' , '' , N'女')insert into Student values('08' , N'王菊' , '' , 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"课程成绩高的学生的信息及课程分数--1.1、查询同时存在"01"课程和"02"课程的情况select a.* , b.score [课程'01'的分数],c.score [课程'02'的分数] from Student a , SC b , SC cwhere a.S# = b.S# and a.S# = c.S# and b.C# = '01' and c.C# = '02' and b.score & c.score--1.2、查询同时存在"01"课程和"02"课程的情况和存在"01"课程但可能不存在"02"课程的情况(不存在时显示为null)(以下存在相同内容时不再解释)select a.* , b.score [课程"01"的分数],c.score [课程"02"的分数] from Student aleft 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"课程成绩低的学生的信息及课程分数--2.1、查询同时存在"01"课程和"02"课程的情况select a.* , b.score [课程'01'的分数],c.score [课程'02'的分数] from Student a , SC b , SC cwhere a.S# = b.S# and a.S# = c.S# and b.C# = '01' and c.C# = '02' and b.score & c.score--2.2、查询同时存在"01"课程和"02"课程的情况和不存在"01"课程但存在"02"课程的情况select a.* , b.score [课程"01"的分数],c.score [课程"02"的分数] from Student aleft 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、查询平均成绩大于等于60分的同学的学生编号和学生姓名和平均成绩select a.S# , a.Sname , cast(avg(b.score) as decimal(18,2)) avg_scorefrom Student a , sc bwhere a.S# = b.S#group by a.S# , a.Snamehaving cast(avg(b.score) as decimal(18,2)) &= 60order by a.S#
--4、查询平均成绩小于60分的同学的学生编号和学生姓名和平均成绩--4.1、查询在sc表存在成绩的学生信息的SQL语句。select a.S# , a.Sname , cast(avg(b.score) as decimal(18,2)) avg_scorefrom Student a , sc bwhere a.S# = b.S#group by a.S# , a.Snamehaving cast(avg(b.score) as decimal(18,2)) & 60order by a.S#--4.2、查询在sc表中不存在成绩的学生信息的SQL语句。select a.S# , a.Sname , isnull(cast(avg(b.score) as decimal(18,2)),0) avg_scorefrom Student a left join sc bon a.S# = b.S#group by a.S# , a.Snamehaving isnull(cast(avg(b.score) as decimal(18,2)),0) & 60order by a.S#
--5、查询所有同学的学生编号、学生姓名、选课总数、所有课程的总成绩--5.1、查询所有有成绩的SQL。select a.S# [学生编号], a.Sname [学生姓名], count(b.C#) 选课总数, sum(score) [所有课程的总成绩]from Student a , SC bwhere a.S# = b.S#group by a.S#,a.Snameorder by a.S#--5.2、查询所有(包括有成绩和无成绩)的SQL。select a.S# [学生编号], a.Sname [学生姓名], count(b.C#) 选课总数, sum(score) [所有课程的总成绩]from Student a left join SC bon a.S# = b.S#group by a.S#,a.Snameorder by a.S#
--6、查询"李"姓老师的数量--方法1select count(Tname) ["李"姓老师的数量] from Teacher where Tname like N'李%'--方法2select count(Tname) ["李"姓老师的数量] from Teacher where left(Tname,1) = N'李'
--7、查询学过"张三"老师授课的同学的信息select distinct Student.* from Student , SC , Course , Teacherwhere 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"老师授课的同学的信息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、查询学过编号为"01"并且也学过编号为"02"的课程的同学的信息--方法1select 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2select 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3select m.* from Student m where S# in(select S# from(select distinct S# from SC where C# = '01'union allselect distinct S# from SC where C# = '02') t group by S# having count(1) = 2)order by m.S#
--10、查询学过编号为"01"但是没有学过编号为"02"的课程的同学的信息--方法1select 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2select 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、查询没有学全所有课程的同学的信息--11.1、select Student.*from Student , SCwhere Student.S# = SC.S#group by Student.S# , Student.Sname , Student.Sage , Student.Ssex having count(C#) & (select count(C#) from Course)--11.2select Student.*from Student left join SCon 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"的同学所学相同的同学的信息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"号的同学学习的课程完全相同的其他同学的信息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"老师讲授的任一门课程的学生姓名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及格课程的同学的学号，姓名及其平均成绩select student.S# , student.sname , cast(avg(score) as decimal(18,2)) avg_score from student , scwhere 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生信息select student.* , sc.C# , sc.score from student , scwhere 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所有学生的所有课程的成绩以及平均成绩--17.1 SQL 2000 静态select a.S# 学生编号 , a.Sname 学生姓名 ,max(ame when N'语文' then b.score else null end) [语文],max(ame when N'数学' then b.score else null end) [数学],max(ame 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 aleft join SC b on a.S# = b.S#left join Course c on b.C# = c.C#group by a.S# , a.Snameorder by 平均分 desc--17.2 SQL 2000 动态declare @sql nvarchar(4000)set @sql = 'select a.S# ' + N'学生编号' + ' , a.Sname ' + N'学生姓名'select @sql = @sql + ',max(ame when N'''+Cname+''' then b.score else null end) ['+Cname+']'from (select distinct Cname from Course) as tset @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)
--24、查询学生平均成绩及其名次--24.1 查询学生的平均成绩并进行排名，sql 2000用子查询完成，分平均成绩重复时保留名次空缺和不保留名次空缺两种。select t1.* , px = (select count(1) from(select m.S# [学生编号] ,m.Sname [学生姓名] ,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) t2 where 平均成绩 & t1.平均成绩) + 1 from(select m.S# [学生编号] ,m.Sname [学生姓名] ,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
select t1.* , px = (select count(distinct 平均成绩) from(select m.S# [学生编号] ,m.Sname [学生姓名] ,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) t2 where 平均成绩 &= t1.平均成绩) from(select m.S# [学生编号] ,m.Sname [学生姓名] ,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--24.2 查询学生的平均成绩并进行排名，sql 2005用rank,DENSE_RANK完成，分平均成绩重复时保留名次空缺和不保留名次空缺两种。select t.* , px = rank() over(order by [平均成绩] desc) from(select m.S# [学生编号] ,m.Sname [学生姓名] ,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) torder by px
select t.* , px = DENSE_RANK() over(order by [平均成绩] desc) from(select m.S# [学生编号] ,m.Sname [学生姓名] ,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) torder by px--25、查询各科成绩前三名的记录--25.1 分数重复时保留名次空缺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 分数重复时不保留名次空缺，合并名次--sql 2000用子查询实现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、查询每门课程被选修的学生数select c# , count(S#)[学生数] from sc group by C#
--27、查询出只有两门课程的全部学生的学号和姓名select Student.S# , Student.Snamefrom Student , SCwhere Student.S# = SC.S#group by Student.S# , Student.Snamehaving count(SC.C#) = 2order by Student.S#
--28、查询男生、女生人数select count(Ssex) as 男生人数 from Student where Ssex = N'男'select count(Ssex) as 女生人数 from Student where Ssex = N'女'select sum(case when Ssex = N'男' then 1 else 0 end) [男生人数],sum(case when Ssex = N'女' then 1 else 0 end) [女生人数] from studentselect case when Ssex = N'男' then N'男生人数' else N'女生人数' end [男女情况] , count(1) [人数] from student group by case when Ssex = N'男' then N'男生人数' else N'女生人数' end
--29、查询名字中含有"风"字的学生信息select * from student where sname like N'%风%'select * from student where charindex(N'风' , sname) & 0
--30、查询同名同性学生名单，并统计同名人数select Sname [学生姓名], count(*) [人数] from Student group by Sname having count(*) & 1
--31、查询1990年出生的学生名单(注：Student表中Sage列的类型是datetime)select * from Student where year(sage) = 1990select * from Student where datediff(yy,sage,'') = 0select * from Student where datepart(yy,sage) = 1990select * from Student where convert(varchar(4),sage,120) = '1990'
--32、查询每门课程的平均成绩，结果按平均成绩降序排列，平均成绩相同时，按课程编号升序排列select m.C# , m.Cname , cast(avg(n.score) as decimal(18,2)) avg_scorefrom Course m, SC nwhere m.C# = n.C# group by m.C# , m.Cnameorder by avg_score desc, m.C# asc
--33、查询平均成绩大于等于85的所有学生的学号、姓名和平均成绩select a.S# , a.Sname , cast(avg(b.score) as decimal(18,2)) avg_scorefrom Student a , sc bwhere a.S# = b.S#group by a.S# , a.Snamehaving cast(avg(b.score) as decimal(18,2)) &= 85order by a.S#
--34、查询课程名称为"数学"，且分数低于60的学生姓名和分数select sname , scorefrom Student , SC , Coursewhere SC.S# = Student.S# and SC.C# = Course.C# ame = N'数学' and score & 60
--35、查询所有学生的课程及分数情况；select Student.* , ame , SC.C# , SC.score from Student, SC , Coursewhere Student.S# = SC.S# and SC.C# = Course.C#order by Student.S# , SC.C#
--36、查询任何一门课程成绩在70分以上的姓名、课程名称和分数；select Student.* , ame , SC.C# , SC.score from Student, SC , Coursewhere Student.S# = SC.S# and SC.C# = Course.C# and SC.score &= 70order by Student.S# , SC.C#
--37、查询不及格的课程select Student.* , ame , SC.C# , SC.score from Student, SC , Coursewhere Student.S# = SC.S# and SC.C# = Course.C# and SC.score & 60order by Student.S# , SC.C#
--38、查询课程编号为01且课程成绩在80分以上的学生的学号和姓名；select Student.* , ame , SC.C# , SC.score from Student, SC , Coursewhere Student.S# = SC.S# and SC.C# = Course.C# and SC.C# = '01' and SC.score &= 80order by Student.S# , SC.C#
--39、求每门课程的学生人数select Course.C# , ame , count(*) [学生人数]from Course , SCwhere Course.C# = SC.C#group by Course.C# , ameorder by Course.C# , ame
--40、查询选修"张三"老师所授课程的学生中，成绩最高的学生信息及其成绩--40.1 当最高分只有一个时select top 1 Student.* , ame , SC.C# , SC.score from Student, SC , Course , Teacherwhere 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 当最高分出现多个时select Student.* , ame , SC.C# , SC.score from Student, SC , Course , Teacherwhere Student.S# = SC.S# and SC.C# = Course.C# and Course.T# = Teacher.T# and Teacher.Tname = N'张三' andSC.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、查询不同课程成绩相同的学生的学生编号、课程编号、学生成绩--方法1select m.* from SC m ,(select C# , score from SC group by C# , score having count(1) & 1) nwhere m.C#= n.C# and m.score = n.score order by m.C# , m.score , m.S#--方法2select m.* from SC m where exists (select 1 from (select C# , score from SC group by C# , score having count(1) & 1) nwhere m.C#= n.C# and m.score = n.score) order by m.C# , m.score , m.S#
--42、查询每门功成绩最好的前两名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、统计每门课程的学生选修人数（超过5人的课程才统计）。要求输出课程号和选修人数，查询结果按人数降序排列，若人数相同，按课程号升序排列 select Course.C# , ame , count(*) [学生人数]from Course , SCwhere Course.C# = SC.C#group by Course.C# , amehaving count(*) &= 5order by [学生人数] desc , Course.C#
--44、检索至少选修两门课程的学生学号select student.S# , student.Snamefrom student , SCwhere student.S# = SC.S#group by student.S# , student.Snamehaving count(1) &= 2order by student.S#
--45、查询选修了全部课程的学生信息--方法1 根据数量来完成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 使用双重否定来完成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 使用双重否定来完成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、查询各学生的年龄--46.1 只按照年份来算select * , datediff(yy , sage , getdate()) [年龄] from student--46.2 按照出生日期来算，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、查询本周过生日的学生select * from student where datediff(week,datename(yy,getdate()) + right(convert(varchar(10),sage,120),6),getdate()) = 0
--48、查询下周过生日的学生select * from student where datediff(week,datename(yy,getdate()) + right(convert(varchar(10),sage,120),6),getdate()) = -1
--49、查询本月过生日的学生select * from student where datediff(mm,datename(yy,getdate()) + right(convert(varchar(10),sage,120),6),getdate()) = 0
--50、查询下月过生日的学生select * from student where datediff(mm,datename(yy,getdate()) + right(convert(varchar(10),sage,120),6),getdate()) = -1
drop table Student,Course,Teacher,SC
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TA的最新馆藏[转]&SQL命令 “学生”数据库中有 “学生表”、“课程表”和 “成绩表”。 “学生表”中包含学号、姓名_百度知道java习题：在MySQL数据库建立一个学生信息表(学号,姓名,班级,成绩),编程完成如下操作java习题：在MySQL数据库建立一个学生信息表(学号,姓-知识宝库
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