2. 给出相应的INSERT语句来完成题中给出数据的插入。
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;
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数据库sql
4. 列出教师所在的单位depart(不重复)。
命令:select distinct 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 except select name from Student where name like '王%';或
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数据库sql
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=85 or degree=86 or degree=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';
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数据库sql
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 distinct cno from Score where degree>85;
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(cast(degree as float)) 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(cast(degree as float)),MAX(degree),MIN(degree) from Score where cno like '3%' group by cno having COUNT(cno)>5; 或者:
select cno,AVG(cast(DEGREE as float)),MAX(degree),MIN(DEGREE) from Score group by cno having COUNT(cno)>=5 and cno like '3%'
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 Student.no,name from Student join Score on
Student.no=Score.no
group
by
Student.no,name
having
MAX(Score.degree)<90 and MIN(Score.degree)>70;
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 join Course on Teacher.no=Course.tno
where Course.cno in(select cno from Score group by cno having COUNT(Score.cno)>5);
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数据库sql
19. 输出’95001’班级所选课程的课程号和平均分
命令:select cno,avg(cast(degree as float)) from Score where no
in(select no from Student where class=95001) group by cno;
或者:
select cno,AVG(cast(degree as float)) from Score join Student on Score.no=Student.no group by cno,class having class='95001'
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(class)>=2;
或者:select a.class from (select * from Student where sex='男') a group by a.class having COUNT(a.class)>=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 no,name,birthday from Student where year(birthday)
=(select year(birthday) from Student where no=108);
或者:select b.no,b.name,b.birthday from Student a join Student b on datediff(YEAR,a.birthday,b.birthday)=0 and a.no='108'
22. 列出存在有85分以上成绩的课程名称
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数据库sql
命令:select cname from Course where cno in (select distinct cno from
Score where degree>85);或
select distinct cname from Course join Score on Course.cno=Score.cno where degree>85;
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 Course.cno,cname,Student.name,DEGREE from Teacher join
Course on Teacher.no=Course.tno join Score on Course.cno=Score.cno join Student on Score.no=Student.no where Teacher.depart='计算机系';
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
select a.name,a.prof,b.name,b.prof from (select
name,prof,depart from Teacher where depart='计算机系' or depart='电子工程系') a join (select name,prof,depart from Teacher where depart='电子工程系' or depart='计算机系') b on not a.prof=b.prof and not a.depart=b.depart;
令:
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 join Student b on not a.class=b.class and a.birthday=b.birthday;
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 join Course on
Teacher.no=Course.tno join Score on Course.cno=Score.cno join Student on Score.no=Student.no where Teacher.name='张三';
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数据库sql
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 join Course on Teacher.no=Course.tno join Score on 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 left join Score on
Student.no=Score.no;
select name,Student.no,DEGREE from Student join Score on Student.no=Score.no;
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数据库sql
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 join Course on
Teacher.no=Course.tno;
select distinct name,depart from Teacher join Course on Teacher.no=Course.tno join Score on Course.cno=Score.cno;
30. 输出男教师所上课程名称。
命令:select cname from Teacher join Course on Teacher.no=Course.tno where Teacher.sex='男';
31. 出与“李军”同性别的所有同学的name。
命令:select name from Student where sex=(select sex from Student where 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 join Student on Score.no=Student.no
join Course on Score.cno=Course.cno where sex='男' and cname='数据结构';
33. 列出选修编号为‘3-105’课程并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 Course.cno,Score.no,DEGREE from Course join Score on
Course.cno=Score.cno join Student on Score.no=Student.no where Course.cno='3-105' and Score.degree>(select max(degree) from Score where Score.cno='3-111');
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 in(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 Student.no,name from Student join Score on Student.no
=Score.no where Score.cno='3-105' and degree>(select degree from Score where no='109' and cno='3-105');
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,a.avg_degree from Score join (select
cno,AVG(cast(degree as float)) from Score group by cno) a(cno,avg_degree)
on
Score.cno=a.cno
where
Score.degree
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数据库sql
37. 列出没有实际授课的教师的姓名和系别
命令:select name,depart from Teacher except select name,depart from
Teacher join Course on Teacher.no=Course.tno join Score on 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 cno='3-105' and degree>(select MAX(degree) from Score where cno='4-109');
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,a.avg_degree-b.avg_degree as
difference from (select Student.no,name,avg(degree) from Student join Score
on
Student.no=Score.no
group
by
Student.no,name)
a(no,name,avg_degree) join (select Student.no,name,avg(degree) from Student join Score on Student.no=Score.no group by Student.no,name) b(no,name,avg_degree) on a.avg_degree>b.avg_degree;