mysql练习总结

nkion
2024年 6月 27日

整理45道mysql的经典练习题。

题目：

【数据库和表设计 --学生表 | 课程表 | 成绩表 | 教师表】

CREATE TABLE students(

sno VARCHAR(3) NOT NULL,

sname VARCHAR(4) NOT NULL,

ssex VARCHAR(2) NOT NULL,

sbirthday DATE NOT NULL,

class VARCHAR(5)

);

CREATE TABLE courses(

cno VARCHAR(5) NOT NULL,

cname VARCHAR(10) NOT NULL,

tno VARCHAR(10) NOT NULL

);

CREATE TABLE scores (

sno VARCHAR(3) NOT NULL,

cno VARCHAR(5) NOT NULL,

degree NUMERIC(10, 1) NOT NULL

);

CREATE TABLE teachers (

tno VARCHAR(3) NOT NULL,

tname VARCHAR(4) NOT NULL,

tsex VARCHAR(2) NOT NULL,

tbirthday DATETIME NOT NULL,

prof VARCHAR(6) NOT NULL,

depart VARCHAR(10) NOT NULL

);

select * from STUDENTS;

INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (108 ,'曾华' ,'男' ,'1977-09-01',95033);

INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (105 ,'匡明' ,'男' ,'1975-10-02',95031);

INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (107 ,'王丽' ,'女' ,'1976-01-23',95033);

INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (101 ,'李军' ,'男' ,'1976-02-20',95033);

INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (109 ,'王芳' ,'女' ,'1975-02-10',95031);

INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (103 ,'陆君' ,'男' ,'1974-06-03',95031);

select * from COURSES;

INSERT INTO COURSES(CNO,CNAME,TNO)VALUES ('3-105' ,'计算机导论',825);

INSERT INTO COURSES(CNO,CNAME,TNO)VALUES ('3-245' ,'操作系统' ,804);

INSERT INTO COURSES(CNO,CNAME,TNO)VALUES ('6-166' ,'数据电路' ,856);

INSERT INTO COURSES(CNO,CNAME,TNO)VALUES ('9-888' ,'高等数学' ,100);

select * from SCORES;

INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (103,'3-245',86);

INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (105,'3-245',75);

INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (109,'3-245',68);

INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (103,'3-105',92);

INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (105,'3-105',88);

INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (109,'3-105',76);

INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (101,'3-105',64);

INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (107,'3-105',91);

INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (108,'3-105',78);

INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (101,'6-166',85);

INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (107,'6-106',79);

INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (108,'6-166',81);

select * from teachers;

INSERT INTO TEACHERS(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART) VALUES (804,'李诚','男','1958-12-02','副教授','计算机系');

INSERT INTO TEACHERS(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART) VALUES (856,'张旭','男','1969-03-12','讲师','电子工程系');

INSERT INTO TEACHERS(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART) VALUES (825,'王萍','女','1972-05-05','助教','计算机系');

INSERT INTO TEACHERS(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART) VALUES (831,'刘冰','女','1977-08-14','助教','电子工程系');

【要求】

1、查询Student表中的所有记录的Sname、Ssex和Class列。

2、查询教师所有的单位即不重复的Depart列。

3、查询Student表的所有记录。

4、查询Score表中成绩在60到80之间的所有记录

5、查询Score表中成绩为85，86或88的记录。

6、查询Student表中“95031”班或性别为“女”的同学记录。

7、以Class降序查询Student表的所有记录。

8、以Cno升序、Degree降序查询Score表的所有记录。

9、查询“95031”班的学生人数。

10、查询Score表中的最高分的学生学号和课程号。

11、查询‘3-105’号课程的平均分。

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。

13、查询最低分大于70，最高分小于90的Sno列。

14、查询所有学生的Sname、Cno和Degree列。

15、查询所有学生的Sno、Cname和Degree列。

16、查询所有学生的Sname、Cname和Degree列。

17、查询“95033”班所的课程的平均分。

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。

20、查询score中选学一门以上课程的同学中分数为非最高分成绩的记录。

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。

22、查询和学号为107的同学同年出生的所有学生的Sno、Sname和Sbirthday列。

23、查询“张旭“教师任课的学生成绩。

24、查询选修某课程的同学人数多于5人的教师姓名。

25、查询95033班和95031班全体学生的记录。

26、查询存在有85分以上成绩的课程Cno.

27、查询出“计算机系“教师所教课程的成绩表。

28、查询“计算机系”与“电子工程系“不同职称的教师的Tname和Prof。

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。

30、查询选修编号为“3-105”且成绩高于任意选修编号为“3-245”课程的同学的Cno、Sno和Degree.

31、查询所有教师和同学的name、sex和birthday.

32、查询所有“女”教师和“女”同学的name、sex和birthday.

33、查询成绩比该课程平均成绩低的同学的成绩表。

34、查询所有任课教师的Tname和Depart.

35 查询所有未讲课的教师的Tname和Depart.

36、查询至少有2名男生的班号。

37、查询Student表中不姓“王”的同学记录。

38、查询Student表中每个学生的姓名和年龄。

39、查询Student表中最大和最小的Sbirthday日期值。

40、以班号和年龄从大到小的顺序查询Student表中的全部记录。

41、查询“男”教师及其所上的课程。

42、查询最高分同学的Sno、Cno和Degree列。

43、查询和“李军”同性别的所有同学的Sname.

44、查询和“李军”同性别并同班的同学Sname.

45、查询所有选修“计算机导论”课程的“男”同学的成绩表

我的答案：

SELECT sname,ssex,class from students; -- #1

SELECT count(*),depart FROM teachers GROUP BY depart; -- #2

SELECT * from students; -- #3

SELECT *FROM scores WHERE degree>60 and degree<80; -- #4

SELECT * FROM scores WHERE degree in(85,86,88); -- #5

SELECT * FROM students WHERE class=95031 || ssex='女'; -- #6

SELECT * FROM students ORDER BY class DESC; -- #7

SELECT * FROM scores ORDER BY cno ASC, degree DESC; -- #8

SELECT COUNT(*) AS '95031班的人数' FROM students WHERE class=95031; -- #9

SELECT sno,cno FROM scores WHERE degree=(SELECT MAX(degree) FROM scores); -- #10

SELECT sno,cno FROM scores ORDER BY degree DESC LIMIT 1; -- #11

SELECT AVG(degree)FROM scores WHERE cno IN(SELECT cno FROM scores GROUP BY cno HAVING COUNT(cno)>5 AND LEFT(cno,1)='3');
-- #12

SELECT AVG(DEgree) FROM scores WHERE cno in(SELECT cno FROM scores WHERE cno LIKE '3%' GROUP BY cno HAVING COUNT(*) >= 5); -- #13

SELECT sno,degree FROM scores WHERE degree>70 AND degree<90; -- #14

SELECT students.sname,scores.cno,scores.degree from students INNER JOIN scores ON students.sno=scores.sno; -- #15

SELECT scores.sno,courses.cname,scores.degree FROM scores INNER JOIN courses ON scores.cno=courses.cno; -- #16

SELECT students.sname,courses.cname,scores.degree FROM students INNER JOIN scores ON students.sno=scores.sno
INNER JOIN courses ON scores.cno=courses.cno; -- #17

SELECT AVG(degree) FROM scores INNER JOIN students ON scores.sno=students.sno WHERE class='95033'; -- #18

SELECT * FROM scores WHERE cno='3-105' AND (SELECT max(degree) FROM scores WHERE sno=109); -- #19

SELECT sno,degree,count(*) as '选课门数' FROM scores WHERE degree<(SELECT MAX(degree) FROM scores) GROUP BY sno HAVING 选课门数>1 ; -- #20

SELECT * FROM scores WHERE degree>(SELECT degree FROM scores WHERE sno=109 and cno='3-105'); -- #21

SELECT sno,sname,sbirthday FROM students WHERE year(sbirthday)=(SELECT YEAR(sbirthday) FROM students WHERE sno=107); -- #22

SELECT degree FROM scores INNER JOIN courses ON scores.cno=courses.cno
INNER JOIN teachers ON teachers.tno=courses.tno WHERE teachers.tname='张旭'; -- #23

SELECT teachers.tname,count(*) AS '同学数量' FROM scores INNER JOIN courses ON scores.cno=courses.cno
INNER JOIN teachers ON teachers.tno=courses.tno GROUP BY teachers.tname HAVING 同学数量>5; -- #24

SELECT * FROM students WHERE class=95033 ||class=95031; -- #25

SELECT cno,degree FROM scores GROUP BY cno HAVING degree>85; -- #26

SELECT cname,degree FROM scores INNER JOIN courses ON scores.cno=courses.cno
INNER JOIN teachers ON courses.tno=teachers.tno WHERE teachers.tname in(SELECT tname FROM teachers WHERE depart='计算机系'); -- #27

SELECT tname,prof FROM teachers WHERE depart in('计算机系','电子工程系') GROUP BY prof; -- #28

SELECT cno,sno,degree FROM scores WHERE cno='3-105'AND degree>(SELECT degree FROM scores
WHERE cno='3-245' ORDER BY degree ASC LIMIT 1) ORDER BY degree DESC; -- #29

SELECT cno,sno,degree FROM scores WHERE cno='3-105'AND degree>(SELECT degree FROM scores WHERE cno='3-245'
ORDER BY degree DESC LIMIT 1) ORDER BY degree DESC; -- #30

SELECT students.sname,students.ssex,students.sbirthday,teachers.tname,teachers.tsex,teachers.tbirthday FROM students
INNER JOIN scores ON students.sno=scores.sno INNER JOIN courses ON scores.cno=courses.cno
INNER JOIN teachers ON courses.tno=teachers.tno; -- #31

SELECT sname,scores.cno,scores.degree,avg_scores.avgdg FROM students INNER JOIN scores ON students.sno=scores.sno
INNER JOIN(SELECT cno,avg(degree) AS avgdg FROM scores GROUP BY cno)AS avg_scores ON scores.cno=avg_scores.cno
WHERE scores.degree<avg_scores.avgdg; -- #33

SELECT tname, depart FROM teachers; -- #34

SELECT tname, depart FROM teachers LEFT JOIN courses ON teachers.tno=courses.tno
LEFT JOIN scores ON courses.cno=scores.cno WHERE courses.tno is NULL; -- #35

select class from students where ssex = '男' group by class having count(ssex) >= 2; -- #36

SELECT * from students WHERE sname NOT LIKE '王%'; -- #37

SELECT sname,year(CURDATE())-year(sbirthday) FROM students; -- #38

SELECT MAX(sbirthday),MIN(sbirthday) FROM students; -- #39

SELECT *,year(CURDATE())-year(sbirthday)AS age FROM students ORDER BY class DESC,age DESC; -- #40

SELECT tname,cname from teachers INNER JOIN courses ON teachers.tno=courses.tno WHERE tsex='男'; -- #41

SELECT sno,cno,degree FROM scores ORDER BY degree DESC LIMIT 1; -- #42

SELECT sname,ssex FROM students WHERE ssex=(SELECT ssex FROM students WHERE sname='李军'); -- #43

SELECT sname,class FROM students WHERE ssex=(SELECT ssex FROM students WHERE sname='李军')
AND class=(SELECT class FROM students WHERE sname='李军'); -- #44

SELECT sname,degree FROM students INNER JOIN scores ON students.sno=scores.sno
INNER JOIN courses ON scores.cno=courses.cno WHERE ssex='男' AND cname='计算机导论'; -- #45

比较有代表性的，8，12，22，24，2733，35，37，44，45。

留着自己复习。

没有评论在学术类其他

欢迎你

nkion 的个人博客

mysql练习总结

题目：

我的答案：

比较有代表性的，8，12，22，24，2733，35，37，44，45。

留着自己复习。