概述
继前两次的实验,本次实验以熟练掌握利用select语句进行各种查询操作:单表查询、多表连接及查询、嵌套查询、集合查询等,巩固数据库查询操作。
下面就跟着小编一起练习吧!
在实验一创建并插入数据的表(Student, Course,SC,Teacher,TC)的基础上,完成以下操作。
(1)将教师‘罗莉'的名字改为‘罗莉莉'。
复制代码 代码如下:
update Teacher set tname='罗莉莉' where tname='罗莉'
(2)将两个同学(数据自己临时设置,用后即删除)的两门课程的成绩以运行sql程序文件的形式插入score表中。该题用以验证、理解和掌握关系模型的完整性规则;
插入:
复制代码 代码如下:
insert into Score(sno,cno,grade) values ('04261006','C003','64')
insert into Score(sno,cno,grade) values('04261007','C004','79')
insert into Score(sno,cno,grade) values('04261007','C004','79')
查询:
复制代码 代码如下:
select sno 学号,cno 课程号,grade 分数from Score where sno=04261006 or sno=04261007;
删除:
复制代码 代码如下:
delete from Score where sno=04261006 or sno=04261007;
(3)求每门课的平均成绩,并把结果存入average表(自行设计并创建);
复制代码 代码如下:
CREATE TABLE average
(
cno CHAR(8),
avscore numeric(5,2),
constraint a1 primary key (cno),
constraint a2 foreign key (cno) references Course(cno),
)
insert into average(cno,avscore)
select distinct cno ,avg(grade) from Score group by cno
(
cno CHAR(8),
avscore numeric(5,2),
constraint a1 primary key (cno),
constraint a2 foreign key (cno) references Course(cno),
)
insert into average(cno,avscore)
select distinct cno ,avg(grade) from Score group by cno
(4)将学生“马丽”的年龄改为24;
复制代码 代码如下:
Update Student set 2014-year(Sbirth) 年龄 where Sname=' 马丽'
(5)将所有学生的szipcode属性列值填补上;
复制代码 代码如下:
update Student set szipcode='221000'
(6)将average表中的所有课程的平均成绩置零;
复制代码 代码如下:
update average set avscore='0'
(7)删除average表中的课程号为‘C007'的平均成绩记录;
复制代码 代码如下:
delete from average where cno='C007'
(8)删除所有average表中平均成绩记录;
复制代码 代码如下:
delete from average;
(9)建立一个临时学生信息表(tstudent),删除该表中的学号含‘101'的所有学生记录。
复制代码 代码如下:
create table tstudent ( Sno char(8) primary key, Sname varchar(8) unique );
Delete from tstudent where Sno like '001011%';
Delete from tstudent where Sno like '001011%';
(10)查询全体学生的学号与姓名;
复制代码 代码如下:
select sno 学号,sname 姓名from Student
(11)查询全体学生的学号、姓名、所属系;
复制代码 代码如下:
select sno 学号,sname 姓名,sdept 系from Student
(12)查询全体学生的详细记录;
复制代码 代码如下:
select * from Student
(13)查询全体学生的姓名及其年龄;
复制代码 代码如下:
select sname 姓名,2014-year(sbirth) 年龄from Student
(14)查询全体学生的姓名、出生年份;
复制代码 代码如下:
select sname 姓名,year(sbirth) 出生年份from Student
(15)查询所有修过课的学生的学号;
复制代码 代码如下:
select distinct sno from Score
select distinct student.sno from Student,Score where Student.sno=Score.sno and Score.grade>0 ;
select distinct student.sno from Student,Score where Student.sno=Score.sno and Score.grade>0 ;
(16)查询“计算机系”班全体学生名单;
复制代码 代码如下:
select sno,sname from Student where sdept='计算机系'
(17)查询查询所有年龄在23岁以下的学生姓名及其年龄;
复制代码 代码如下:
select sname 姓名,2014-year(sbirth) 年龄from Student where 2014-year(sbirth)<23;
(18)查询考试成绩有不及格的学生的学号;
复制代码 代码如下:
select distinct sno from Score where grade<60;
(19)查询年龄在20至22岁之间的学生姓名、系和年龄;
复制代码 代码如下:
select sname 姓名,sdept 系,2014-year(sbirth) 年龄from student where 2014-year(sbirth) between 20 and 22;
(20)查询年龄不在20至22岁之间的学生姓名、系和年龄;
复制代码 代码如下:
select sname 姓名,sdept 系,2014-year(sbirth) 年龄from student where 2014-year(sbirth) not between 20 and 22;
(21)查询“计算机系”和“电商系”的学生的姓名;
复制代码 代码如下:
select sname from Student where sdept='计算机系' or sclass='电商系'
(22)查询既不是“计11”也不是“计61”班的学生的姓名和班级信息;
复制代码 代码如下:
select sname,sclass from Student where sclass not in('计','计');
(23)查询学号为“04262002”的学生的详细情况;
[code]select student.sno,sname,ssex,2014-year(sbirth),sclass,grade from Student,Score where Student.sno=Score.sno and Student.sno='04262002';
(23)查询学号为“04262002”的学生的详细情况;
[code]select student.sno,sname,ssex,2014-year(sbirth),sclass,grade from Student,Score where Student.sno=Score.sno and Student.sno='04262002';
(24)查询学号以“04262”打头的学生信息;
复制代码 代码如下:
select * from Student where sno like '04262%'
(25)查询所有姓“张”学生的学号、姓名、性别、年龄;
复制代码 代码如下:
select sno 学号,sname 姓名,ssex 性别,2011-year(sbirth) 年龄from Student where sname like'王%'
(26)查询名字中第二个字有“海”字的学生的学号、姓名、性别、年龄;
复制代码 代码如下:
select sno 学号,sname 姓名,ssex 性别,2011-year(sbirth) 年龄from Student where sname like '_田%'
(27)查询所有不姓“刘”学生的姓名;
复制代码 代码如下:
select sname 姓名from Student where sname not like '刘%'
(28)查询课程号以“C”开头的最后两个字母为“05”的课程号和课程名;
复制代码 代码如下:
select cno,cname from Course where cno like 'C%05'
(29)某些学生选修某门课程后没有参加考试,所以有选修课记录,但没有考试成绩,试查找缺少考试成绩的学生和相应的课程号;
复制代码 代码如下:
select Student.sno,sname,cno from Student,Score where Student.sno=Score.sno and grade is NULL;
(30)查找全部有成绩记录的学生学号、课程号;
复制代码 代码如下:
select sno, cno from Score where grade is not NULL;
(31)查找“计算机系”年龄在22岁以下的学生学号、姓名;
复制代码 代码如下:
select sno ,sname from Student where sdept='计算机系' and 2014-year(sbirth)<22
(32)查找选修了“C001”号课程的学生学号及其成绩,查询结果按分数降序排序;
复制代码 代码如下:
select student.sno,grade from student,Score where Student.sno=Score.sno and cno='C001' order by grade desc;
(33)查询全体学生情况,查询结果按所在系升序排列,对同一系中的学生按年龄降序排列;
复制代码 代码如下:
select * from student order by sdept asc,2014-year(sbirth) desc;
(34)查询学生总人数;
复制代码 代码如下:
select count(*) 人数from Student;
(35)查询选修了课程的学生人数;
复制代码 代码如下:
select count(distinct sno)人数from Score;
(36)在所有课程中查询最高分的学生学号和成绩;
复制代码 代码如下:
select sno,grade from Score where grade =(select max(grade)from Score )
复制代码 代码如下:
select distinct a.* from Score a where a.sno IN (select top 1 Score.sno from Score where Score.cno = a.cno order by grade desc)
(37)查询学习“C001”课程的学生最高分数;
复制代码 代码如下:
select max(grade)最高分数from Score where cno='C001'
(38)计算各个课程号与相应的选课人数;
复制代码 代码如下:
select count(sno) 选课人数from Score group by cno;
(39)查询“计算机系”选修了两门课程以上的学生学号、姓名;
复制代码 代码如下:
select Student.sno,sname from Student where Student.sno in
(select Student.sno from Student,Score where
sdept='计算机系'and Student.sno=Score.sno group by Student.sno having count(cno)>=2);
(select Student.sno from Student,Score where
sdept='计算机系'and Student.sno=Score.sno group by Student.sno having count(cno)>=2);
(40)自然连接student和score表;
复制代码 代码如下:
select student.*,Score.grade from student ,Score where student.sno=Score.sno;
(41)使用自身连接查询每一门课程的间接先行课(即先行课的先行课)
复制代码 代码如下:
select a.cno,b.cpno from Course a,Course b where a.cpno=b.cno;
(42)使用复合条件连接查询选修“c001”号课程且成绩在90分以上的所有同学;
复制代码 代码如下:
select sname,grade from student,Score where Student.sno=Score.sno and cno='C001' and grade>=90;
(43)使用复合条件连接查询每个学生选修的课程名及其成绩;
复制代码 代码如下:
select Student.sno,sname,cname,grade from Course,Score,Student where Course.cno=Score.cno and student.sno=Score.sno;
(44)查询选修了全部课程的学生;
复制代码 代码如下:
select Sname from Student where not exists (select * from Course where not exists(select * from Score where Sno=Student.Sno and Cno=Course.Cno))
(45)查询所有选修了C001号课程的学生学号、姓名;
复制代码 代码如下:
select student.sno,sname from student,Score where student.sno=Score.sno and cno='C001';
(46)查询选修了课程C001或C007的学生学号、姓名;
[code]select student.sno,sname,cno from student,Score where student.sno=Score.sno and cno in ('C001','C007');
[/code](46)查询选修了课程C001或C007的学生学号、姓名;
[code]select student.sno,sname,cno from student,Score where student.sno=Score.sno and cno in ('C001','C007');
(47)查询“计算机系”的学生及年龄不大于23岁的学生;
复制代码 代码如下:
select sno ,sname,2014-year(sbirth) age ,sclass from student where sdept='计算机系' or 2014-year(sbirth)<=23;
(48)查询既选修了课程C001又选修了课程C007的所有学生学号、姓名;
复制代码 代码如下:
select student.sno,sname from student,Score where student.sno=Score.sno and cno='C001' and student.sno in (select student.sno from student,Score where student.sno=Score.sno and cno='C007')
(49)查询选修了课程名为“数据库原理”的学生的学号、姓名、性别、年龄;
复制代码 代码如下:
select student.sno ,sname,ssex,cname,2011-year(sbirth) age from student,Score,Course where student.sno=Score.sno and Score.cno=Course.cno and cname='数据库原理';
(50)查询其他班中比“计算机系”所有学生年龄都小的学生名单;
复制代码 代码如下:
select sno,sname ,2014-year(sbirth) age from student where 2014-year(sbirth)<(select min(2014-year(sbirth)) from student where sclass='计61')and sclass !='计61';
(51)查询与“夏天”在同一个系学习的学生学号、姓名、性别、年龄;
复制代码 代码如下:
select sno,sname,ssex,2014-year(sbirth) age from student where sdept=(select sdept from student where sname='夏天') and sname!='夏天'
(52)建立“计算机系”学生的视图1;
复制代码 代码如下:
create view view_student
as select sno,sname,ssex,sbirth,sclass from student where sclass='13z网络'
as select sno,sname,ssex,sbirth,sclass from student where sclass='13z网络'
(53)建立“计算机系”学生的视图2,并要求进行修改与插入时,仍须保证该视图只有“计算机系”班学生;
复制代码 代码如下:
create view view_student2
as select sno,sname,ssex,sbirth,sclass from student where sclass='13z网络' with check option;
as select sno,sname,ssex,sbirth,sclass from student where sclass='13z网络' with check option;
(54)建立“计算机系”选修了“C001”课程的学生的视图,定义视图名为“v_cs_C001_student1”;
复制代码 代码如下:
create view v_cs_C001_student1
as select student.sno,sname,ssex,sbirth,sclass from Student ,Score where
student.sno=Score.sno and sclass='13z网络' and cno='C001';
as select student.sno,sname,ssex,sbirth,sclass from Student ,Score where
student.sno=Score.sno and sclass='13z网络' and cno='C001';
(55)建立“计算机系”班选修了“C001”课程且成绩在90分以上的学生的视图,定义视图名为“cs_c001_student2”;
复制代码 代码如下:
create view cs_c001_student2
as
select student.sno,sname ,ssex,sbirth,sclass,cno from student,Score where
student.sno=Score.sno and cno='C001' and sclass='13z网络'and student.sno in (select student.sno from student,Score where student.sno=Score.sno and grade>90)
as
select student.sno,sname ,ssex,sbirth,sclass,cno from student,Score where
student.sno=Score.sno and cno='C001' and sclass='13z网络'and student.sno in (select student.sno from student,Score where student.sno=Score.sno and grade>90)
(56)定义一个反映学生年龄的视图,定义视图名为“v_birth_student”;
复制代码 代码如下:
create view v_birth_student
as
select sno,sname,2014-year(sbirth) age from student
as
select sno,sname,2014-year(sbirth) age from student
(57)将学生表中所有女生记录定义为一个视图,视图名为“v_female_student”;
复制代码 代码如下:
create view v_female_student
as
select * from student where ssex='女';
as
select * from student where ssex='女';
(58)将学生的学号及其平均成绩定义为一个视图,视图名为“v_average_student”;
复制代码 代码如下:
create view v_average_student
as
select sno,avg(grade) avscore from Score group by sno;
as
select sno,avg(grade) avscore from Score group by sno;
(59)在“计算机系”学生视图中找出年龄小于22岁的学生;
复制代码 代码如下:
select * from view_student where 2014-year(sbirth)<=22;
(60)利用视图查询“计算机系”选修了“C001”课程的学生;
复制代码 代码如下:
select * from v_cs_C001_student1;
(61)通过(52)中的“计算机系”视图修改某个学生的名字;
复制代码 代码如下:
update view_student set sname='王某某'where sno=04261001;
(62)通过(53)中的“计算机系”视图,插入一个新学生记录。
复制代码 代码如下:
insert into view_student2(sno,sname,ssex,sbirth,sclass) values ('04262004','张某某','男','1987/11/09','计');
(63)通过(53)中的“计算机系”视图,删除一个学生记录。
复制代码 代码如下:
delete from view_student2 where sno='04262004'and sname='张某某';
实验课结束了,相信通过本节课的实践操作,小伙伴们都对数据库表的操作有了更进一步的了解。
以上就是查询数据库表的基本操作,几乎涵盖了各种查询操作所遇到的情况,值得大家亲自操作一下,相信对大家的学习有所帮助。
最后
以上就是机智苗条为你收集整理的数据库表的查询操作实践演练(实验三)的全部内容,希望文章能够帮你解决数据库表的查询操作实践演练(实验三)所遇到的程序开发问题。
如果觉得靠谱客网站的内容还不错,欢迎将靠谱客网站推荐给程序员好友。
本图文内容来源于网友提供,作为学习参考使用,或来自网络收集整理,版权属于原作者所有。
发表评论 取消回复