云想衣裳花想容，春风拂槛露华浓。
若非群玉山头见，会向瑶台月下逢。
现在有一教学管理系统，具体的关系模式如下：
Student (no, name, sex, birthday, class)
Teacher (no, name, sex, birthday, prof, depart)
Course (cno, cname, tno)
Score (no, cno, degree)
其中表中包含如下数据：
Course表：
Score表：
Student表：
Teacher表：
根据上面描述完成下面问题：
（注意：注意保存脚本，尤其是DDL和DML，以便进行数据还原）
DDL
1.写出上述表的建表语句。
命令：
create table Student (no int, name varchar(30), sex char(2), birthday datetime, class int);
create table Teacher (no int, name varchar(30), sex char(2), birthday datetime, prof varchar(20), depart varchar(30));
create table Course (cno varchar(10), cname varchar(30), tno int);
create table Score (no int, cno varchar(10), degree float);
DML
2.给出相应的INSERT语句来完成题中给出数据的插入。
命令：
insert into Student values(5001,'李勇','男','1987-07-22 00:00:00.000',95001);
insert into Student values(5002,'刘晨','女','1987-11-15 00:00:00.000',95002);
insert into Student values(5003,'王敏','女','1987-10-5 00:00:00.000',95001);
insert into Student values(5004,'李好尚','男','1987-9-25 00:00:00.000',95003);
insert into Student values(5005,'李军','男','1987-7-17 00:00:00.000',95004);
insert into Student values(5006,'范新位','女','1987-6-18 00:00:00.000',95005);
insert into Student values(5007,'张霞东','女','1987-8-29 00:00:00.000',95006);
insert into Student values(5008,'赵薇','男','1987-6-15 00:00:00.000',95007);
insert into Student values(5009,'钱民将','女','1987-6-23 00:00:00.000',95008);
insert into Student values(5010,'孙俪','女','1987-9-24 00:00:00.000',95002);
insert into Student values(108,'赵里','男','1987-6-15 00:00:00.000',95007);
insert into Student values(109,'丘处机','男','1987-6-23 00:00:00.000',95008);
insert into Student values(107,'杨康','男','1987-9-24 00:00:00.000',95001);
insert into Teacher values('1','李卫','男','1957-11-5','教授','电子工程');
insert into Teacher values('2','刘备','男','1967-10-9','副教授','math');
insert into Teacher values('3','关羽','男','1977-9-20','讲师','cs');
insert into Teacher values('4','李修','男','1957-6-25','教授','elec');
insert into Teacher values('5','诸葛亮','男','1977-6-15','教授','计算机系');
insert into Teacher values('6','殷素素','女','1967-1-5','副教授','cs');
insert into Teacher values('7','周芷若','女','1947-2-23','教授','cs');
insert into Teacher values('8','赵云','男','1980-6-15','副教授','计算机系');
insert into Teacher values('9','张敏','女','1985-5-5','助教','cs');
insert into Teacher values('10','黄蓉','女','1967-3-22','副教授','cs');
insert into Teacher values('11','张三','男','1967-3-22','副教授','cs');
insert into Course values('3-101','数据库',1);
insert into Course values('5-102','数学',3);
insert into Course values('3-103','信息系统',4);
insert into Course values('3-104','操作系统',6);
insert into Course values('3-105','数据结构',4);
insert into Course values('3-106','数据处理',5);
insert into Course values('4-107','Pascal语言',5);
insert into Course values('4-108','c++',7);
insert into Course values('4-109','Java',8);
insert into Course values('3-245','数据挖掘',10);
insert into Course values('3-111','软件工程',11);
insert into Score values(5001,'3-105',69);
insert into Score values(5001,'5-102',55);
insert into Score values(5003,'4-108',85);
insert into Score values(5004,'3-105',77);
insert into Score values(5005,'3-245',100);
insert into Score values(5006,'3-105',53);
insert into Score values(5003,'4-109',45);
insert into Score values(5008,'3-105',98);
insert into Score values(5004,'4-109',68);
insert into Score values(5010,'3-105',88);
insert into Score values(5003,'3-105',98);
insert into Score values(5005,'4-109',68);
insert into Score values(5002,'3-105',88);
insert into Score values(107,'3-105',98);
insert into Score values(108,'4-109',68);
insert into Score values(109,'3-105',88);
insert into Score values(109,'4-109',80);
insert into Score values(107,'3-111',88);
insert into Score values(5003,'3-111',80);
单表查询
3.以class降序输出student的所有记录（student表全部属性）
命令：
select * from Student order by class desc;
4.列出教师所在的单位depart（不重复）。
命令：
select count(depart) from Teacher;
5.列出student表中所有记录的name、sex和class列
命令：
select name, sex, class from Student;
6.输出student中不姓王的同学的姓名。
命令：
select name from Student where name not like '王%';
7.输出成绩为85或86或88或在60-80之间的记录（no,cno,degree）
命令：
select no, cno, degree from Score where degree in(85, 86, 88) or degree between 60 and 80;
8.输出班级为95001或性别为‘女’ 的同学（student表全部属性）
命令：
select * from Student where class = 95001 or sex = '女';
9.以cno升序、degree降序输出score的所有记录。（score表全部属性）
命令：
select * from Score order by cno asc, degree desc;
10.输出男生人数及这些男生分布在多少个班级中
命令：
select count(*), count(distinct class) from Student where sex = '男';
11.列出存在有85分以上成绩的课程编号。
命令：
select cno from Score where degree > 85 group by cno;
12.输出95001班级的学生人数
命令：
select count(*) from Student where class = 95001;
13.输出‘3-105’号课程的平均分
命令：
select avg(degree) from Score where cno = '3-105';
14.输出student中最大和最小的birthday日期值
命令：
select max(birthday), min(birthday) from Student;
15.显示95001和95004班全体学生的全部个人信息（不包括选课）。（student表全部属性）
命令：
select * from Student where class = 95001 or class = 95004;
聚合查询
16.输出至少有5个同学选修的并以3开头的课程的课程号，课程平均分，课程最高分，课程最低分。
命令：select cno, avg(degree), max(degree), min(degree) from Score where cno like '3%' group by cno having count(*) >= 5;
17.输出所选修课程中最低分大于70分且最高分小于90分的学生学号及学生姓名
命令：
select no,name from Student where no in(select no from Score group by no having min(degree) > 70 and max(degree) < 90);
18.显示所教课程选修人数多于5人的教师姓名
命令：
select name from Teacher where no in(select tno from
Course where cno in (select cno from score
group by cno having count(cno) > 5));
19.输出’95001’班级所选课程的课程号和平均分
命令：select cno, avg(degree) from Score where no in (select no from Student where class = 95001) group by cno;
20.输出至少有两名男同学的班级编号。
命令：select class from Student where sex = '男' group by class having count(*) >= 2;
多表查询
21.列出与108号同学同年出生的所有学生的学号、姓名和生日
命令：select a.no, a.name, a.birthday from Student a, Student b where b.no = 108 and year(b.birthday) = year(a.birthday)
22.列出存在有85分以上成绩的课程名称
命令：
select cname from Course where cno in (select cno from Score where degree > 85 group by cno);
select cname from Course, (select cno from Score where Score.degree > 85 group by cno) t where Course.cno = t.cno;
23.列出“计算机系”教师所教课程的成绩表（课程编号，课程名，学生名，成绩）。
命令：
select Score.cno, cname, Student.name, degree from Teacher, Course, Student, Score where Teacher.depart = '计算机系' and Teacher.no = Course.tno and Course.cno = Score.cno and Student.no = Score.no;
24.列出所有可能的“计算机系”与“电子工程系”不同职称的教师配对信息，要求输出每个老师的姓名（name）和（职称）
命令：select a.name, a.prof, b.name, b.prof from Teacher a, Teacher b where a.depart in ('计算机系', '电子工程') and b.depart in('计算机系', '电子工程') and a.prof != b.prof and a.depart != b.depart;
25.列出所有处于不同班级中，但具有相同生日的学生，要求输出每个学生的学号和姓名。（提示：使用datediff函数，具体用法可以参考：http://hcmfys.javaeye.com/blog/588844）
命令：select a.no, a.name, b.no, b.name from Student a, Student b where a.class != b.class and datediff(day, a.birthday, b.birthday) = 0;
26.显示‘张三’教师任课的学生姓名，课程名，成绩
命令：select Student.name, cname, degree from Teacher, Student, Course, Score where Teacher.name = '张三' and Teacher.no = Course.tno and Course.cno = Score.cno and Student.no = Score.no;
27.列出所讲课已被选修的教师的姓名和系别
命令：select distinct name, depart from Teacher, Course, Score where Teacher.no = Course.tno and Course.cno = Score.cno;
28.输出所有学生的name、no和degree。（degree为空的不输出和为空的输出两种情况）。
命令：select name, Student.no, degree from Student, Score where Student.no = Score.no;
select name, Student.no, degree from Student left join Score on Student.no = Score.no;
29.列出所有任课教师的name和depart。（从课程选修和任课两个角度考虑）
命令：select distinct name, depart from Teacher, Course where Teacher.no = Course.tno;
select distinct name, depart from Teacher, Course, Score where Teacher.no = Course.tno and Score.cno = Course.cno;
30.输出男教师所上课程名称。
命令：
select cname from Teacher, Course where Teacher.sex = '男' and Course.tno = Teacher.no;
31.出与“李军”同性别的所有同学的name。
命令：
select a.name from Student a, Student b where a.sex = b.sex and b.name = '李军';
32.输出选修“数据结构”课程的男同学的成绩。
命令：
select degree from Score, Course, Student where Score.cno = Course.cno and Course.cname = '数据结构' and Student.no = Score.no and Student.sex = '男';
33.列出选修编号为‘3-105’课程且该门课程成绩比课程‘3-111’的最高分要高的cno,no和degree。
命令：select Score.cno, no, degree from Score, (select cno, max(degree) maxdegree from Score group by cno) t where Score.cno = '3-105' and t.cno = '3-111' and Score.degree > t.maxdegree;
子查询
34.输出score中成绩最高的学号和课程号
命令：select no, cno from Score where degree = (select max(degree) from Score);
35.输出选修3-105课程，其成绩高于109号同学在此课程所得成绩的所有同学的学号，姓名
命令：select a.no, Student.name from Score a, Score b, Student where a.cno = '3-105' and b.cno = '3-105'and b.no = 109 and a.degree > b.degree and a.no = Student.no;
36.列出成绩比该课程平均成绩低的同学的学号，成绩和该门课的平均成绩
命令：
select no, degree, avg_degree from Score, (select cno, avg(degree) avg_degree from Score group by cno) t where Score.degree < t.avg_degree and Score.cno = t.cno;
37.列出没有实际授课的教师的姓名和系别
命令：select distinct name, depart from Teacher where no not in (select tno from Course, Score where Course.cno = Score.cno);
38.列出选修了编号为‘3-105’课程且其成绩高于‘4-109’课程最高成绩的同学的 课程编号，学号和成绩
命令：
select cno, no, degree from Score where degree > (select max(degree) from Score where cno = '4-109') and cno = '3-105';
39.**列出符合下述条件的所有可能的同学配对（sno1,sname1,sno2,sname2,difference）。其中要求学号为sno1的sname1同学的所学课程的平均分大于学号为sno2的sname2同学的所学课程平均分，两个同学的课程平均分的差值difference为（sno1同学平均分-sno2同学平均分）
命令：
select a.no, a.name, b.no, b.name, c.avgdegree - d.avgdegree difference from Student a, Student b, (select no, avg(degree) avgdegree from Score group by no) c,(select no, avg(degree) avgdegree from Score group by no) d where a.no = c.no and b.no = d.no and c.avgdegree > d.avgdegree;
