SQL练习题,MySQL数据库查询语句经典例题练习，附带答案和运行效果截图以供参考

请按照以下顺序创建这4张表

1.首先

创建student和teacher表

2.其次

创建score成绩表和course课程表

注意:

1.假如 student表和 teacher表没有创建出来，在创建 score表或者 course表的时候， 当设置外键的时候会提示字段或表不存在。
2.所以需要首先创建出来 student和 teacher表，在创建 score和 course表

数据库中共有4张表，每张表的详细情况如下

1、student学生表属性

属性名	数据类型	长度	是否为空	注释
Sno	char	3	否	学号(主键)
Sname	char	8	否	学生姓名
Ssex	char	2	否	学生性别
Sbirthday	datetime	0	是	学生生日
Sclass	char	5	是	学生所在班级

2、course课程表属性

属性名	数据类型	长度	是否为空	注释
Cno	char	5	否	课程号(主键)
Cname	varchar	10	否	课程名称
Tno	char	3	否	教工号(外键)

3、score成绩表属性

属性名	数据类型	长度	是否为空	注释
Sno	char	3	否	学号(主键)
Cno	char	5	否	课程号(主键+外键)
Degree	decimal	10	是	成绩

4、teacher教师表属性

属性名	数据类型	长度	是否为空	注释
Tno	char	3	否	教工号(主键)
Tname	char	4	否	教工姓名
Tsex	char	2	否	教工性别
Tbirthday	datetime	0	是	教工生日
Prof	char	6	是	教工职称
Depart	varchar	10	否	教工所在专业

---

表格中的数据如下所示：

1、student表数据

Sno	Sname	Ssex	Sbirthday	Sclass
108	曾华	男	1977-09-01	95033
105	匡明	男	1975-10-02	95031
107	王丽	女	1976-01-23	95033
101	李军	男	1976-02-20	95033
109	王芳	女	1975-02-10	95031
103	陆君	男	1974-06-03	95031

2、course表数据

Cno	Cname	Tno
3-105	计算机导论	825
3-245	操作系统	804
6-166	数字电路	856
9-888	高等数学	831

3、score表数据

Sno	Cno	Degree
103	3-245	86
105	3-245	75
109	3-245	68
103	3-105	92
105	3-105	88
109	3-105	76
101	3-105	64
107	3-105	91
108	3-105	78
101	6-116	85
107	6-116	79
108	6-116	81

4、teacher表数据

Tno	Tname	Tsex	Tbirthday	Prof	Depart
804	李诚	男	1958-12-02	副教授	计算机系
856	张旭	男	1969-03-12	讲师	电子工程系
825	王萍	女	1972-05-05	助教	计算机系
831	刘冰	女	1977-08-14	助教	电子工程系

---

以下每条查询语句都会附带上查询结果的截图

1、 查询student表中的所有的Sname、Ssex和Class列。

SELECT
    Sname,
    Ssex,
    Sclass
FROM
    student;

2、 查询教师所有的单位即不重复的Depart列

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

SELECT
    *
FROM
    score
WHERE
    Degree BETWEEN 60
AND 80;

5、查询Score表中成绩为85，86或88的所有记录。

SELECT
    *
FROM
    score
WHERE
    Degree = 85
OR Degree = 86
OR Degree = 88;

6、查询student表中“95031”班或性别为“女”的同学的所有记录

SELECT
    *
FROM
    student
WHERE
    Sclass = 95031
OR Ssex = '女';

7、以Sclass降序查询student表的所有记录

SELECT
    *
FROM
    student
ORDER BY
    Sclass DESC;

8、以Cno升序、Degree降序查询score表的所有记录

SELECT
    *
FROM
    score
ORDER BY
    Cno,
    Degree DESC;

9、查询“95031”班的学生人数

SELECT
    COUNT(Sclass) AS 学生人数
FROM
    student
WHERE
    Sclass = 95031;

10、查询score表中的最高分的学生学号和课程号

SELECT
    MAX(Degree) Cno,
    Sno
FROM
    score;

11、查询每门课的平均成绩和Cno

SELECT
    AVG(Degree),
    Cno
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

SELECT
    AVG(Degree) AS 平均分
FROM
    score
WHERE
    Cno = (
        SELECT
            Cno
        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

SELECT DISTINCT
    Sno
FROM
    score
WHERE
    Degree BETWEEN 70
AND 90;

14、查询所有学生的Sname、Cno和Degree列

SELECT
    student.Sname,
    score.Cno,
    score.Degree
FROM
    student,
    score 
WHERE
    student.Sno = score.Sno;

15、查询所有学生的Sno、Cname和Degree列

SELECT
    student.Sname,
    score.Sno,
    score.Degree
FROM
    score,
    course,
    student
WHERE
    score.Cno = course.Cno
AND student.Sno = score.Sno;

16、查询所有学生的Sname、Cname和Degree列

SELECT
    student.Sname,
    course.Cname,
    score.Degree
FROM
    student,
    score,
    course
WHERE
    student.Sno = score.Sno
AND score.Cno = course.Cno

17、查询“95033”班学生的平均分。

SELECT
    student.Sclass,
    AVG(score.Degree)
FROM
    score,
    student
WHERE
    score.Sno = student.Sno
AND student.Sclass = 95033
GROUP BY
    student.Sclass;

19、查询选修“3-105”课程且成绩高于“109”号同学成绩的所有同学的记录

SELECT
    *
FROM
    score
WHERE
    Degree IN (
        SELECT
            Degree
        FROM
            score
        WHERE
            Degree > (
                SELECT
                    Degree
                FROM
                    score
                WHERE
                    Cno = '3-105'
                AND Sno = 109
            )
    )
ORDER BY
    Degree ASC;

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

SELECT
    *
FROM
    score
WHERE
    Degree NOT IN (SELECT MAX(Degree) FROM score)
AND Sno IN (
    SELECT
        Sno
    FROM
        score
    GROUP BY
        Sno
    HAVING
        COUNT(*) >= 2
)

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
            Degree
        FROM
            score
        WHERE
            Sno = 109
        AND Cno = '3-105'
    )
ORDER BY
    Degree;

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

SELECT
    Sno,
    Sname,
    Sbirthday
FROM
    student
WHERE
    YEAR (Sbirthday) = (
        SELECT
            YEAR (Sbirthday)
        FROM
            student
        WHERE
            Sno = 107
    )

23、查询选修了”张旭”教师的课程的学生成绩Degree，学号Sno，课号Cno

SELECT 
        *
    FROM
        score,
        teacher,
        course
    WHERE
        teacher.Tname = '张旭'
    AND teacher.Tno = course.Tno
    AND course.Cno = score.Cno

24、查询选修人数多于5人的课程所对应的教师的姓名

SELECT
    teacher.Tname
FROM
    teacher,
    course,
    score
WHERE
    score.Cno = (
        SELECT
            score.Cno
        FROM
            score
        GROUP BY
            score.Cno
        HAVING
            COUNT(*) >= 5
    )
AND course.Cno = score.Cno
AND course.Tno = teacher.Tno
GROUP BY
    teacher.Tname;

25、查询95033班和95031班全体学生的记录

SELECT DISTINCT
    *
FROM
    student,
    score,
    course
WHERE
    (
        student.Sclass = 95033
        OR student.Sclass = 95031
    )
AND student.Sno = score.Sno
AND score.Cno = course.Cno
ORDER BY
    student.Sclass;

26、查询成绩在85分以上的课程的Cno

SELECT DISTINCT
    score.Cno
FROM
    score
WHERE
    Degree > 85;

27、查询出”计算机系”教师所教课程的成绩表Sno,Sname,Ssex,Sclass,Cno,Degree,Cname

SELECT
    student.Sno,
    student.Sname,
    student.Ssex,
    student.Sclass,
    score.Cno,
    score.Degree,
    course.Cname
FROM
    student,
    score,
    course,
    teacher
WHERE
    teacher.Depart = '计算机系'
AND teacher.Tno = course.Tno
AND course.Cno = score.Cno
AND student.Sno = score.Sno;

28、查询“计算机系”与“电子工程系“不同职称的教师的Tname和Prof

SELECT
    Tname,
    Prof
FROM
    teacher
WHERE
    Prof NOT IN (
        SELECT
            Prof
        FROM
            teacher
        WHERE
            Depart = '计算机系'
        AND Prof IN (
            SELECT
                Prof
            FROM
                teacher
            WHERE
                Depart = '电子工程系'
        )
    )

29、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、Degree和Sname.

SELECT
    student.Sno,
    student.Sname,
    score.Cno,
    score.Degree
FROM
    student,
    score
WHERE
    score.Degree > (
        SELECT DISTINCT
            MAX(score.Degree)
        FROM
            score
        WHERE
            score.Cno = '3-245'
    )
AND score.Cno = '3-105'
AND score.Sno = student.Sno

30、查询所有教师和同学的name、sex和birthday

SELECT
    student.Sname,
    student.Ssex,
    student.Sbirthday
FROM
    student
UNION
    SELECT
        teacher.Tname,
        teacher.Tsex,
        teacher.Tbirthday
    FROM
        teacher;

31、查询所有“女”教师和“女”同学的name、sex和birthday

SELECT
    student.Sname,
    student.Ssex,
    student.Sbirthday
FROM
    student
WHERE
    student.Ssex = '女'
UNION
    SELECT
        teacher.Tname,
        teacher.Tsex,
        teacher.Tbirthday
    FROM
        teacher
    WHERE
        teacher.Tsex = '女';

32、查询成绩比该课程平均成绩低的同学的成绩表Sno，Sname，Cno，Degree

SELECT
    student.Sno,
    student.Sname,
    Cno,
    Degree
FROM
    student,
    score AS scoreA
WHERE
    Degree < (
        SELECT
            AVG(Degree)
        FROM
            score AS scoreB
        WHERE
            scoreA.Cno = scoreB.Cno
        GROUP BY
            Cno
    )
AND student.Sno = scoreA.Sno
ORDER BY
    scoreA.Cno;

33、查询所有任课教师的Tname和Depart

SELECT DISTINCT
    teacher.Tname,
    teacher.Depart
FROM
    teacher,
    course,
    score
WHERE
    teacher.Tno = course.Tno
AND course.Cno = score.Cno;

34、查询所有未讲课的教师的Tname和Depart

SELECT DISTINCT
    teacher.Tname,
    teacher.Depart
FROM
    teacher
WHERE
    teacher.Tname NOT IN (
        SELECT DISTINCT
            teacher.Tname
        FROM
            teacher,
            course,
            score
        WHERE
            teacher.Tno = course.Tno
        AND course.Cno = score.Cno
    )

35、查询至少有2名男生的班级号Sclass

SELECT
    student.Sclass
FROM
    student
WHERE
    student.Ssex = '男'
GROUP BY
    student.Sclass
HAVING
    COUNT(1) > 1

36、查询至少有2名男生的课程的课程号Cno

SELECT
    score.Cno
FROM
    score,
    student
WHERE
    student.Ssex = '男'
GROUP BY
    score.Cno
HAVING
    COUNT(1) > 1

36、查询不姓王的同学信息

SELECT
    *
FROM
    student
WHERE
    student.Sname NOT IN (
        SELECT
            student.Sname
        FROM
            student
        WHERE
            student.Sname LIKE '王%'
    )
GROUP BY
    student.Sname
ORDER BY
    student.Sclass;

37、查询Student表中每个学生的姓名Sname和年龄

SELECT
    student.Sname,
    YEAR (NOW()) - YEAR (student.Sbirthday) AS 年龄
FROM
    student

38、查询Student表中最大和最小的日期值Sbirthday

SELECT
    MIN(student.Sbirthday) AS 最大,
    MAX(student.Sbirthday) AS 最小
FROM
    student;

39、以班号和年龄从大到小的顺序查询Student表中的全部记录

SELECT
    *
FROM
    student
ORDER BY
    student.Sclass DESC,
    student.Sbirthday ASC;

40、查询“男”教师及其所上的课程

SELECT
    teacher.Tno,
    teacher.Tname,
    teacher.Tsex,
    course.Cname
FROM
    teacher,
    course
WHERE
    teacher.Tsex = '男'
AND teacher.Tno = course.Tno;

41、查询最高分同学的Sno、Cno和Degree列

SELECT DISTINCT
    score.Sno,
    score.Cno,
    score.Degree
FROM
    score
WHERE
    score.Degree IN (
        SELECT
            MAX(score.Degree)
        FROM
            score
    )

42、查询和“李军”同性别的所有同学的Sname

SELECT
    student.Sname,
    student.Ssex
FROM
    student
WHERE
    student.Ssex IN (
        SELECT
            student.Ssex
        FROM
            student
        WHERE
            student.Sname = '李军'
    )

43、查询和“李军”同性别并同班的同学Sname.

SELECT
    student.Sname,
    student.Ssex,
    student.Sclass
FROM
    student
WHERE
    student.Ssex IN (
        SELECT
            student.Ssex
        FROM
            student
        WHERE
            student.Sname = '李军'
    )
AND student.Sclass IN (
    SELECT
        student.Sclass
    FROM
        student
    WHERE
        student.Sname = '李军'
)

44、查询所有选修“计算机导论”课程的“男”同学的成绩表

SELECT
    student.Sno,
    student.Sname,
    student.Ssex,
    course.Cname,
    score.Degree
FROM
    student,
    score,
    course
WHERE
    course.Cname = '计算机导论'
AND student.Ssex = '男'
AND student.Sno = score.Sno
AND course.Cno = score.Cno
GROUP BY
    student.Sname
ORDER BY
    student.Sno;