create database School use School go create table Student --1.学生表 ( Sno varchar(20) not null primary key,--学号(主码) Sname varchar(20) not null,--学生姓名 Ssex varchar(20) not null,--学生性别 Sbirthday datetime,--学生出生年月 Class varchar(20),--学生所在班级 ) go create table Teacher --4.教师表 ( Tno varchar(20) not null primary key,--教工编号(主) Tname varchar(20) not null,--教工姓名 Tsex varchar(20) not null,--教工性别 Tbirthday datetime,--教工出生年月 Prof varchar(20),--职称 Depart varchar(20) not null,--教工所在部门 ) go create table Course --2.课程表 ( Cno varchar(20) not null primary key,--课程号(主) Cname varchar(20) not null,--课程名称 Tno varchar(20) not null references Teacher(Tno),--教工编号(外) ) go create table Score --3.成绩表 ( Sno varchar(20) not null references Student(Sno),--学号(外) Cno varchar(20) not null references Course(Cno),--课程号(外) Degree decimal(4,1),--成绩 ) alter table Score add constraint Pk_Score primary key (Sno,Cno) --添加两个主键 --学生信息 insert into Student values('108','曾华','男','1977-09-01','95033') insert into Student(Sno,Sname,Ssex,Sbirthday,Class)values('105','匡明','男','1975-10-02','95031') insert into Student values('107','王丽','女','1976-01-23','95033') insert into Student values('101','李军','男','1976-02-20','95033') insert into Student values('109','王芳','女','1975-02-10','95031') insert into Student values('103','陆君','男','1974-06-03','95031') --职工信息 insert into Teacher values('804','李诚','男','1958-12-02','副教授','计算机系') insert into Teacher values('856','张旭','男','1969-03-12','讲师','电子工程系') insert into Teacher values('825','王萍','女','1972-05-05','助教','计算机系') insert into Teacher values('831','刘冰','女','1977-08-14','助教','电子工程系') --课程 insert into Course values('3-105','计算机导论','825') insert into Course values('3-245','操作系统','804') insert into Course values('6-166','数字电路','856') insert into Course values('9-888','高等数学','831') --成绩 insert into Score values('103','3-245','86') insert into Score values('105','3-245','75') insert into Score values('109','3-245','68') insert into Score values('103','3-105','92') insert into Score values('105','3-105','88') insert into Score values('109','3-105','76') insert into Score values('101','3-105','64') insert into Score values('107','3-105','91') insert into Score values('108','3-105','78') insert into Score values('101','6-166','85') insert into Score values('107','6-166','79') insert into Score values('108','6-166','81') --1、 查询Student表中的所有记录的Sname、Ssex和Class列。 select Sname,Ssex,Class from Student --2、 查询教师所有的单位即不重复的Depart列。 --去重 distinct select distinct Depart from Teacher --3、 查询Student表的所有记录。 select * from Student --4、 查询Score表中成绩在60到80之间的所有记录。 --范围查询 比较运算符 select * from Score where Degree>=60 and Degree<=80 --between...and... select * from Score where Degree between 60 and 80 --5、 查询Score表中成绩为85,86或88的记录。 select * from Score where Degree=85 or Degree=86 or Degree=88 --离散查询 select * from Score where Degree in (85,86,88) --6、 查询Student表中“95031”班或性别为“女”的同学记录。 select * from Student where Class='95031' or Ssex='女' --7、 以Class降序查询Student表的所有记录。 --排序order by 升序asc 降序desc select * from Student order by Class desc --8、 以Cno升序、Degree降序查询Score表的所有记录。 select * from Score order by Cno asc,Degree desc --9、 查询“95031”班的学生人数。 --个数count(*) select Class,COUNT(*) from Student group by Class having Class=95031 select count(*) from student where class='95031' --10、 查询Score表中的最高分的学生学号和课程号。(子查询或者排序) --子查询 select Sno,Cno from Score where Degree=(select max(Degree) from Score) --降序取第一条数据 select top 1 Sno,Cno from Score order by Degree desc --11、 查询每门课的平均成绩。 --平均分用avg(列) select Cno,AVG(Degree) as '平均分' from Score group by Cno --12、查询Score表中至少有5名学生选修的并以3开头的课程的平均分数。 --模糊查询 like 分组 group by...having... select Cno,AVG(Degree) as '平均分' from Score group by Cno having COUNT(Cno)>=5 and Cno like'3%' select avg(degree) from score where cno like'3%' group by cno having count(*)>=5 --13、查询分数大于70,小于90的Sno列。 --范围查询 select Sno from Score where Degree>70 and Degree<90 select Sno from Score where Degree between 70 and 90 --14、查询所有学生的Sname、Cno和Degree列。 --连接查询 select Student.Sname,Cno,Degree from Student,Score where Score.Sno=Student.Sno --join...on... select Sname,Cno,Degree from Student join Score on Student.Sno=Score.Sno --15、查询所有学生的Sno、Cname和Degree列。 select Sno,Cname,Degree from Course,Score where Score.Cno=Course.Cno select Sno,Cname,Degree from Score join Course on Score.Cno=Course.Cno --16、查询所有学生的Sname、Cname和Degree列。 select Sname,Cname,Degree from Student,Course,Score where Student.Sno=Score.Sno and Course.Cno=Score.Cno --17、 查询“95033”班学生的平均分。 select Class='95033',AVG(degree) as '平均分' from Score join Student on Score.Sno=Student.Sno and Class='95033' select avg(degree) from score where sno in(select sno from student where class='95033') --18、 假设使用如下命令建立了一个grade表: create table grade ( low int, upp int, rank varchar(1) ) insert into grade values(90,100,'A') insert into grade values(80,89,'B') insert into grade values(70,79,'C') insert into grade values(60,69,'D') insert into grade values(0,59,'E') --现查询所有同学的Sno、Cno和rank列。 select Sno,Cno,Degree,rank from grade join Score on Score.Degree between low and upp select sno,cno,rank from score,grade where degree between low and upp --19、查询选修“3-105”课程的成绩高于“109”号同学成绩的所有同学的记录。 select * from Score where Degree>(select Degree from Score where Cno='3-105' and Sno='109') and Cno='3-105' select * from Student join Score on Student.Sno=Score.Sno where Cno='3-105' and Degree>(select Degree from Score where Cno='3-105' and Sno='109') --20、查询score中选学多门课程的同学中分数为非最高分成绩的记录。 --反向查询没有出现过得值not in select * from score a where sno in (select sno from score group by sno having count(*)>1) and degree <(select max(degree) from score b where b.cno=a.cno) select * from Score where Sno in(select Sno from Score group by Sno having COUNT(Sno)>=2 )and Degree not in( select max(Degree) from Score group by Cno) --21、查询成绩高于学号为“109”、课程号为“3-105”的成绩的所有记录。 select * from Score where Degree>(select Max(Degree) from Score where Sno='109')and Cno='3-105' --22、查询和学号为108的同学同年出生的所有学生的Sno、Sname和Sbirthday列。 --获取年year(时间日期) select Sno,Sname,Sbirthday from Student where YEAR(Sbirthday)=(select year(Sbirthday) from Student where Sno='108') select Sno,Sname,Sbirthday from Student where year(Sbirthday)=(select year(Sbirthday) from Student where Sno='107') --23、查询“张旭“教师任课的学生成绩。 select * from Score where Cno=(select Cno from Course where Tno=(select Tno from Teacher where Tname='张旭')) --24、查询选修某课程的同学人数多于5人的教师姓名。 select Tname from Teacher where Tno=(select Tno from Course where Cno=(select Cno from Score group by Cno having COUNT(Cno)>5)) select Teacher.Tno,Tname,Cno,Cname from Teacher join Course on Teacher.Tno=Course.Tno where Tname in (select Tname from Teacher where Tno in (select Tno from Course where Cno in (select Cno from Score group by Cno having count(Cno)>=5))) --25、查询95033班和95031班全体学生的记录。 --与 or select * from Student where Class='95033' or Class='95031' --26、查询存在有85分以上成绩的课程Cno. select distinct Cno from Score where Degree>85 --27、查询出“计算机系“教师所教课程的成绩表。 select * from Score where Cno in (select Cno from Course where Tno in (select Tno from Teacher where Depart='计算机系')) --28、查询“计算机系”与“电子工程系“depart不同职称prof的教师的Tname和Prof。 --联合查询 select tname,prof from teacher where depart='计算机系' and prof not in(select prof from teacher where depart='电子工程系') union select tname,prof from teacher where depart='电子工程系' and prof not in(select prof from teacher where depart='计算机系') --相关子查询 select Tname,prof from Teacher a where Prof not in (select Prof from Teacher b where a.Depart!=b.Depart) --29、查询选修编号为“3-105“课程且成绩至少高于选修编号为“3-245”的同学的Cno、Sno和Degree,并按Degree从高到低次序排序。 select Cno,Sno,Degree from Score where Cno='3-105' and Degree >(select MAX(Degree) from Score where Cno='3-245') order by Degree desc --any 列表中任意一个相当于max select * from score where cno='3-105' and degree>any(select degree from score where cno='3-245') --30、查询选修编号为“3-105”且成绩高于选修编号为“3-245”课程的同学的Cno、Sno和Degree. select * from Score where Cno='3-105' and Degree >(select MAX(Degree) from Score where Cno='3-245') --31、查询所有教师和同学的name、sex和birthday. --联合查询 select Tname as name,Tsex as sex,Tbirthday as birthday from Teacher union select Sname,Ssex,Sbirthday from Student --32、查询所有“女”教师和“女”同学的name、sex和birthday. --联合查询 条件查询 select Tname as name,Tsex as sex,Tbirthday as birthday from Teacher where Tsex='女' union select Sname,Ssex,Sbirthday from Student where Ssex='女' --33、查询成绩比该课程平均成绩低的同学的成绩表。 select * from Score a where Degree <(select AVG(Degree) from Score b where a.Cno=b.Cno) --34、查询所有任课教师的Tname和Depart. select Tname,Depart from Teacher --35、查询所有未讲课的教师的Tname和Depart. select Tname,Depart from Teacher where Tno not in (select Tno from Course where Cno in (select distinct Cno from Score)) --36、查询至少有2名男生的班号。 select Class from Student where Ssex='男' group by Class having COUNT(*)>1 --37、查询Student表中不姓“王”的同学记录。 --不像not like select * from Student where Sname not like'王%' select * from Student where Sname not in (select Sname from Student where Sname like '王%') --38、查询Student表中每个学生的姓名和年龄。 --当前系统时间getdate(),获取数据库时间sysdatetime() select Sname as '姓名',YEAR(GETDATE())-YEAR(Sbirthday) as '年龄' from Student --39、查询Student表中最大和最小的Sbirthday日期值。 --最大值max(列)最小值min(列) select MAX(Sbirthday) as '大',MIN(Sbirthday) as '小' from Student --40、以班号和年龄从大到小的顺序查询Student表中的全部记录。 --多个条件进行排序用,连接 select * from Student order by Class desc,Sbirthday desc --41、查询“男”教师及其所上的课程。 select Teacher.Tno,Tname,Tsex,Cno,Cname from Teacher,Course where Teacher.Tno=Course.Tno and Tsex='男' --42、查询最高分同学的Sno、Cno和Degree列。 select * from Score where Degree=(select MAX(Degree) from Score) --43、查询和“李军”同性别的所有同学的Sname. select Sname from Student where Ssex=(select Ssex from Student where Sname='李军') --44、查询和“李军”同性别并同班的同学Sname. select Sname from Student where Ssex in (select Ssex from Student where Sname='李军') and Class in (select Class from Student where Sname='李军') --45、查询所有选修“计算机导论”课程的“男”同学的成绩表。 select * from Score where Cno in (select Cno from Course where Cname='计算机导论') and Sno in (select Sno from Student where Ssex='男')