MySQL作业 (4) 数据表综合练习

数据表综合练习

  • 题目:
  • 1.查询" 01 "课程比" 02 "课程成绩高的学生的信息及课程分数
    • 1.1查询同时存在" 01 "课程和" 02 "课程的情况
    • 1.2查询存在" 01 "课程但可能不存在" 02 "课程的情况(不存在时显示为 null )
    • 1.3查询不存在" 01 "课程但存在" 02 "课程的情况
  • 2.查询平均成绩大于等于 60 分的同学的学生编号和学生姓名和平均成绩
  • 3.查询在 SC 表存在成绩的学生信息
  • 4.查询所有同学的学生编号、学生姓名、选课总数、所有课程的总成绩(没成绩的显示为 null )
    • 4.1 查有成绩的学生信息
  • 5.查询「李」姓老师的数量
  • 6.查询学过「张三」老师授课的同学的信息
  • 7.查询没有学全所有课程的同学的信息
  • 8.查询至少有一门课与学号为" 01 "的同学所学相同的同学的信
  • 9.查询和" 01 "号的同学学习的课程 完全相同的其他同学的信息
  • 10.查询没学过"张三"老师讲授的任一门课程的学生姓名
  • 11.查询两门及其以上不及格课程的同学的学号,姓名及其平均成绩
  • 12.检索" 01 "课程分数小于 60,按分数降序排列的学生信息
  • 13.按平均成绩从高到低显示所有学生的所有课程的成绩以及平均成绩
  • 14.查询各科成绩最高分、最低分和平均分:
  • 15.按各科成绩进行排序,并显示排名, Score 重复时保留名次空缺
    • 15.1 按各科成绩进行排序,并显示排名, Score 重复时合并名次
  • 16.查询学生的总成绩,并进行排名,总分重复时保留名次空缺
    • 16.1 查询学生的总成绩,并进行排名,总分重复时不保留名次空缺
  • 17.统计各科成绩各分数段人数:课程编号,课程名称,[100-85],[85-70],[70-60],[60-0] 及所占百分比
  • 18.查询各科成绩前三名的记录
  • 19.查询每门课程被选修的学生数
  • 20.查询出只选修两门课程的学生学号和姓名
  • 21.查询男生、女生人数
  • 22.查询名字中含有「风」字的学生信息
  • 23.查询同名同性学生名单,并统计同名人数
  • 24.查询 1990 年出生的学生名单
  • 25.查询每门课程的平均成绩,结果按平均成绩降序排列,平均成绩相同时,按课程编号升序排列
  • 26.查询平均成绩大于等于 85 的所有学生的学号、姓名和平均成绩
  • 27.查询课程名称为「数学」,且分数低于 60 的学生姓名和分数
  • 28.查询所有学生的课程及分数情况(存在学生没成绩,没选课的情况)
  • 29.查询任何一门课程成绩在 70 分以上的姓名、课程名称和分数
  • 30.查询不及格的课程
  • 31.查询课程编号为 01 且课程成绩在 80 分以上的学生的学号和姓名
  • 32.求每门课程的学生人数
  • 33.成绩不重复,查询选修「张三」老师所授课程的学生中,成绩最高的学生信息及其成绩
  • 34.成绩有重复的情况下,查询选修「张三」老师所授课程的学生中,成绩最高的学生信息及其成绩
  • 35.查询不同课程成绩相同的学生的学生编号、课程编号、学生成绩
  • 36.查询每门功成绩最好的前两名
  • 37.统计每门课程的学生选修人数(超过 5 人的课程才统计)。
  • 38.检索至少选修两门课程的学生学号
  • 39.查询选修了全部课程的学生信息
  • 40.查询各学生的年龄,只按年份来算
  • 41.按照出生日期来算,当前月日 < 出生年月的月日则,年龄减一
  • 42.查询本周过生日的学生
  • 43.查询下周过生日的学生
  • 44.查询本月过生日的学生
  • 45.查询下月过生日的学生

题目:

数据表介绍

–1.学生表
Student(SId,Sname,Sage,Ssex)
–SId 学生编号,Sname 学生姓名,Sage 出生年月,Ssex 学生性别

–2.课程表
Course(CId,Cname,TId)
–CId 课程编号,Cname 课程名称,TId 教师编号

–3.教师表
Teacher(TId,Tname)
–TId 教师编号,Tname 教师姓名

–4.成绩表
SC(SId,CId,score)
–SId 学生编号,CId 课程编号,score 分数

学生表 Student
create table Student(SId varchar(10),Sname varchar(10),Sage datetime,Ssex varchar(10));
insert into Student values(‘01’ , ‘赵雷’ , ‘1990-01-01’ , ‘男’);
insert into Student values(‘02’ , ‘钱电’ , ‘1990-12-21’ , ‘男’);
insert into Student values(‘03’ , ‘孙风’ , ‘1990-12-20’ , ‘男’);
insert into Student values(‘04’ , ‘李云’ , ‘1990-12-06’ , ‘男’);
insert into Student values(‘05’ , ‘周梅’ , ‘1991-12-01’ , ‘女’);
insert into Student values(‘06’ , ‘吴兰’ , ‘1992-01-01’ , ‘女’);
insert into Student values(‘07’ , ‘郑竹’ , ‘1989-01-01’ , ‘女’);
insert into Student values(‘09’ , ‘张三’ , ‘2017-12-20’ , ‘女’);
insert into Student values(‘10’ , ‘李四’ , ‘2017-12-25’ , ‘女’);
insert into Student values(‘11’ , ‘李四’ , ‘2012-06-06’ , ‘女’);
insert into Student values(‘12’ , ‘赵六’ , ‘2013-06-13’ , ‘女’);
insert into Student values(‘13’ , ‘孙七’ , ‘2014-06-01’ , ‘女’);

mysql> create table Student(SId varchar(10),Sname varchar(10),Sage datetime,Ssex varchar(10));
Query OK, 0 rows affected (0.03 sec)mysql> insert into Student values('01' , '赵雷' , '1990-01-01' , '男');
Query OK, 1 row affected (0.01 sec)
mysql> insert into Student values('02' , '钱电' , '1990-12-21' , '男');
Query OK, 1 row affected (0.00 sec)
mysql> insert into Student values('03' , '孙风' , '1990-12-20' , '男');
Query OK, 1 row affected (0.00 sec)
mysql> insert into Student values('04' , '李云' , '1990-12-06' , '男');
Query OK, 1 row affected (0.00 sec)
mysql> insert into Student values('05' , '周梅' , '1991-12-01' , '女');
Query OK, 1 row affected (0.01 sec)
mysql> insert into Student values('06' , '吴兰' , '1992-01-01' , '女');
Query OK, 1 row affected (0.00 sec
mysql> insert into Student values('07' , '郑竹' , '1989-01-01' , '女');
Query OK, 1 row affected (0.00 sec)
mysql> insert into Student values('09' , '张三' , '2017-12-20' , '女');
Query OK, 1 row affected (0.01 sec)
mysql> insert into Student values('10' , '李四' , '2017-12-25' , '女');
Query OK, 1 row affected (0.01 sec)
mysql> insert into Student values('11' , '李四' , '2012-06-06' , '女');
Query OK, 1 row affected (0.01 sec)
mysql> insert into Student values('12' , '赵六' , '2013-06-13' , '女');
Query OK, 1 row affected (0.01 sec)
mysql> insert into Student values('13' , '孙七' , '2014-06-01' , '女');
Query OK, 1 row affected (0.01 sec)mysql> select * from Student;
+------+-------+---------------------+------+
| SId  | Sname | Sage                | Ssex |
+------+-------+---------------------+------+
| 01   | 赵雷  | 1990-01-01 00:00:00 ||
| 02   | 钱电  | 1990-12-21 00:00:00 ||
| 03   | 孙风  | 1990-12-20 00:00:00 ||
| 04   | 李云  | 1990-12-06 00:00:00 ||
| 05   | 周梅  | 1991-12-01 00:00:00 ||
| 06   | 吴兰  | 1992-01-01 00:00:00 ||
| 07   | 郑竹  | 1989-01-01 00:00:00 ||
| 09   | 张三  | 2017-12-20 00:00:00 ||
| 10   | 李四  | 2017-12-25 00:00:00 ||
| 11   | 李四  | 2012-06-06 00:00:00 ||
| 12   | 赵六  | 2013-06-13 00:00:00 ||
| 13   | 孙七  | 2014-06-01 00:00:00 ||
+------+-------+---------------------+------+
12 rows in set (0.00 sec)mysql>

科目表 Course
create table Course(CId varchar(10),Cname nvarchar(10),TId varchar(10));
insert into Course values(‘01’ , ‘语文’ , ‘02’);
insert into Course values(‘02’ , ‘数学’ , ‘01’);
insert into Course values(‘03’ , ‘英语’ , ‘03’);

mysql> create table Course(CId varchar(10),Cname nvarchar(10),TId varchar(10));
Query OK, 0 rows affected, 1 warning (0.02 sec)mysql> insert into Course values('01' , '语文' , '02');
Query OK, 1 row affected (0.01 sec)
mysql> insert into Course values('02' , '数学' , '01');
Query OK, 1 row affected (0.01 sec)
mysql> insert into Course values('03' , '英语' , '03');
Query OK, 1 row affected (0.00 sec)mysql> select * from Course;
+------+-------+------+
| CId  | Cname | TId  |
+------+-------+------+
| 01   | 语文  | 02   |
| 02   | 数学  | 01   |
| 03   | 英语  | 03   |
+------+-------+------+
3 rows in set (0.00 sec)mysql>

教师表 Teacher
create table Teacher(TId varchar(10),Tname varchar(10));
insert into Teacher values(‘01’ , ‘张三’);
insert into Teacher values(‘02’ , ‘李四’);
insert into Teacher values(‘03’ , ‘王五’);

mysql> create table Teacher(TId varchar(10),Tname varchar(10));
Query OK, 0 rows affected (0.02 sec)mysql> insert into Teacher values('01' , '张三');
Query OK, 1 row affected (0.00 sec)
mysql> insert into Teacher values('02' , '李四');
Query OK, 1 row affected (0.00 sec)
mysql> insert into Teacher values('03' , '王五');
Query OK, 1 row affected (0.01 sec)mysql> select * from Teacher;
+------+-------+
| TId  | Tname |
+------+-------+
| 01   | 张三  |
| 02   | 李四  |
| 03   | 王五  |
+------+-------+
3 rows in set (0.00 sec)mysql>

成绩表 SC
create table SC(SId varchar(10),CId varchar(10),score decimal(18,1));
insert into SC values(‘01’ , ‘01’ , 80);
insert into SC values(‘01’ , ‘02’ , 90);
insert into SC values(‘01’ , ‘03’ , 99);
insert into SC values(‘02’ , ‘01’ , 70);
insert into SC values(‘02’ , ‘02’ , 60);
insert into SC values(‘02’ , ‘03’ , 80);
insert into SC values(‘03’ , ‘01’ , 80);
insert into SC values(‘03’ , ‘02’ , 80);
insert into SC values(‘03’ , ‘03’ , 80);
insert into SC values(‘04’ , ‘01’ , 50);
insert into SC values(‘04’ , ‘02’ , 30);
insert into SC values(‘04’ , ‘03’ , 20);
insert into SC values(‘05’ , ‘01’ , 76);
insert into SC values(‘05’ , ‘02’ , 87);
insert into SC values(‘06’ , ‘01’ , 31);
insert into SC values(‘06’ , ‘03’ , 34);
insert into SC values(‘07’ , ‘02’ , 89);
insert into SC values(‘07’ , ‘03’ , 98);

mysql> create table SC(SId varchar(10),CId varchar(10),score decimal(18,1));
Query OK, 0 rows affected (0.02 sec)mysql> insert into SC values('01' , '01' , 80);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('01' , '02' , 90);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('01' , '03' , 99);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('02' , '01' , 70);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('02' , '02' , 60);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('02' , '03' , 80);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('03' , '01' , 80);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('03' , '02' , 80);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('03' , '03' , 80);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('04' , '01' , 50);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('04' , '02' , 30);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('04' , '03' , 20);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('05' , '01' , 76);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('05' , '02' , 87);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('06' , '01' , 31);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('06' , '03' , 34);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('07' , '02' , 89);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('07' , '03' , 98);
Query OK, 1 row affected (0.01 sec)mysql> select * from SC;
+------+------+-------+
| SId  | CId  | score |
+------+------+-------+
| 01   | 01   |  80.0 |
| 01   | 02   |  90.0 |
| 01   | 03   |  99.0 |
| 02   | 01   |  70.0 |
| 02   | 02   |  60.0 |
| 02   | 03   |  80.0 |
| 03   | 01   |  80.0 |
| 03   | 02   |  80.0 |
| 03   | 03   |  80.0 |
| 04   | 01   |  50.0 |
| 04   | 02   |  30.0 |
| 04   | 03   |  20.0 |
| 05   | 01   |  76.0 |
| 05   | 02   |  87.0 |
| 06   | 01   |  31.0 |
| 06   | 03   |  34.0 |
| 07   | 02   |  89.0 |
| 07   | 03   |  98.0 |
+------+------+-------+
18 rows in set (0.00 sec)mysql>

1.查询" 01 “课程比” 02 "课程成绩高的学生的信息及课程分数

mysql> select * from Student RIGHT JOIN (->     select t1.SId, class1, class2 from->           (select SId, score as class1 from sc where sc.CId = '01')as t1,->           (select SId, score as class2 from sc where sc.CId = '02')as t2->     where t1.SId = t2.SId AND t1.class1 > t2.class2-> )r-> on Student.SId = r.SId;
+------+-------+---------------------+------+------+--------+--------+
| SId  | Sname | Sage                | Ssex | SId  | class1 | class2 |
+------+-------+---------------------+------+------+--------+--------+
| 02   | 钱电  | 1990-12-21 00:00:00 || 02   |   70.0 |   60.0 |
| 04   | 李云  | 1990-12-06 00:00:00 || 04   |   50.0 |   30.0 |
+------+-------+---------------------+------+------+--------+--------+
2 rows in set (0.01 sec)mysql> select * from  (->     select t1.SId, class1, class2->     from->         (SELECT SId, score as class1 FROM sc WHERE sc.CId = '01') AS t1,->         (SELECT SId, score as class2 FROM sc WHERE sc.CId = '02') AS t2->     where t1.SId = t2.SId and t1.class1 > t2.class2-> ) r-> LEFT JOIN Student-> ON Student.SId = r.SId;
+------+--------+--------+------+-------+---------------------+------+
| SId  | class1 | class2 | SId  | Sname | Sage                | Ssex |
+------+--------+--------+------+-------+---------------------+------+
| 02   |   70.0 |   60.0 | 02   | 钱电  | 1990-12-21 00:00:00 ||
| 04   |   50.0 |   30.0 | 04   | 李云  | 1990-12-06 00:00:00 ||
+------+--------+--------+------+-------+---------------------+------+
2 rows in set (0.00 sec)mysql>

1.1查询同时存在" 01 “课程和” 02 "课程的情况

mysql> select * from->     (select * from sc where sc.CId = '01') as t1,->     (select * from sc where sc.CId = '02') as t2-> where t1.SId = t2.SId;
+------+------+-------+------+------+-------+
| SId  | CId  | score | SId  | CId  | score |
+------+------+-------+------+------+-------+
| 01   | 01   |  80.0 | 01   | 02   |  90.0 |
| 02   | 01   |  70.0 | 02   | 02   |  60.0 |
| 03   | 01   |  80.0 | 03   | 02   |  80.0 |
| 04   | 01   |  50.0 | 04   | 02   |  30.0 |
| 05   | 01   |  76.0 | 05   | 02   |  87.0 |
+------+------+-------+------+------+-------+
5 rows in set (0.00 sec)mysql>

1.2查询存在" 01 “课程但可能不存在” 02 "课程的情况(不存在时显示为 null )

mysql> select * from-> (select * from sc where sc.CId = '02') as t2-> right join-> (select * from sc where sc.CId = '01') as t1-> on t1.SId = t2.SId;
+------+------+-------+------+------+-------+
| SId  | CId  | score | SId  | CId  | score |
+------+------+-------+------+------+-------+
| 01   | 02   |  90.0 | 01   | 01   |  80.0 |
| 02   | 02   |  60.0 | 02   | 01   |  70.0 |
| 03   | 02   |  80.0 | 03   | 01   |  80.0 |
| 04   | 02   |  30.0 | 04   | 01   |  50.0 |
| 05   | 02   |  87.0 | 05   | 01   |  76.0 |
| NULL | NULL |  NULL | 06   | 01   |  31.0 |
+------+------+-------+------+------+-------+
6 rows in set (0.00 sec)mysql>

1.3查询不存在" 01 “课程但存在” 02 "课程的情况

mysql> select * from sc-> where sc.SId not in (->     select SId from sc->     where sc.CId = '01'-> )-> AND sc.CId= '02';
+------+------+-------+
| SId  | CId  | score |
+------+------+-------+
| 07   | 02   |  89.0 |
+------+------+-------+
1 row in set (0.00 sec)mysql>

2.查询平均成绩大于等于 60 分的同学的学生编号和学生姓名和平均成绩

mysql> select student.SId,sname,ss from student,(->     select SId, AVG(score) as ss from sc->     GROUP BY SId->     HAVING AVG(score)> 60->     )r-> where student.sid = r.sid;
+------+-------+----------+
| SId  | sname | ss       |
+------+-------+----------+
| 01   | 赵雷  | 89.66667 |
| 02   | 钱电  | 70.00000 |
| 03   | 孙风  | 80.00000 |
| 05   | 周梅  | 81.50000 |
| 07   | 郑竹  | 93.50000 |
+------+-------+----------+
5 rows in set (0.00 sec)mysql> select Student.SId, Student.Sname, r.ss from Student right join(->       select SId, AVG(score) AS ss from sc->       GROUP BY SId->       HAVING AVG(score)> 60-> )r on Student.SId = r.SId;
+------+-------+----------+
| SId  | Sname | ss       |
+------+-------+----------+
| 01   | 赵雷  | 89.66667 |
| 02   | 钱电  | 70.00000 |
| 03   | 孙风  | 80.00000 |
| 05   | 周梅  | 81.50000 |
| 07   | 郑竹  | 93.50000 |
+------+-------+----------+
5 rows in set (0.00 sec)mysql> select s.SId,ss,Sname from(-> select SId, AVG(score) as ss from sc-> GROUP BY SId-> HAVING AVG(score)> 60-> )r left join-> (select Student.SId, Student.Sname from-> Student)s on s.SId = r.SId;
+------+----------+-------+
| SId  | ss       | Sname |
+------+----------+-------+
| 01   | 89.66667 | 赵雷  |
| 02   | 70.00000 | 钱电  |
| 03   | 80.00000 | 孙风  |
| 05   | 81.50000 | 周梅  |
| 07   | 93.50000 | 郑竹  |
+------+----------+-------+
5 rows in set (0.00 sec)mysql>

3.查询在 SC 表存在成绩的学生信息

4.查询所有同学的学生编号、学生姓名、选课总数、所有课程的总成绩(没成绩的显示为 null )

mysql> select s.sid, s.sname,r.coursenumber,r.scoresum-> from (->     (select student.sid,student.sname->     from student->     )s->     left join->     (select->         sc.sid, sum(sc.score) as scoresum, count(sc.cid) as coursenumber->         from sc->         group by sc.sid->     )r->    on s.sid = r.sid-> );
+------+-------+--------------+----------+
| sid  | sname | coursenumber | scoresum |
+------+-------+--------------+----------+
| 01   | 赵雷  |            3 |    269.0 |
| 02   | 钱电  |            3 |    210.0 |
| 03   | 孙风  |            3 |    240.0 |
| 04   | 李云  |            3 |    100.0 |
| 05   | 周梅  |            2 |    163.0 |
| 06   | 吴兰  |            2 |     65.0 |
| 07   | 郑竹  |            2 |    187.0 |
| 09   | 张三  |         NULL |     NULL |
| 10   | 李四  |         NULL |     NULL |
| 11   | 李四  |         NULL |     NULL |
| 12   | 赵六  |         NULL |     NULL |
| 13   | 孙七  |         NULL |     NULL |
+------+-------+--------------+----------+
12 rows in set (0.00 sec)mysql>

4.1 查有成绩的学生信息

mysql> select * from student-> where exists (select sc.sid from sc where student.sid = sc.sid);
+------+-------+---------------------+------+
| SId  | Sname | Sage                | Ssex |
+------+-------+---------------------+------+
| 01   | 赵雷  | 1990-01-01 00:00:00 ||
| 02   | 钱电  | 1990-12-21 00:00:00 ||
| 03   | 孙风  | 1990-12-20 00:00:00 ||
| 04   | 李云  | 1990-12-06 00:00:00 ||
| 05   | 周梅  | 1991-12-01 00:00:00 ||
| 06   | 吴兰  | 1992-01-01 00:00:00 ||
| 07   | 郑竹  | 1989-01-01 00:00:00 ||
+------+-------+---------------------+------+
7 rows in set (0.00 sec)mysql> select * from student-> where student.sid in (select sc.sid from sc);
+------+-------+---------------------+------+
| SId  | Sname | Sage                | Ssex |
+------+-------+---------------------+------+
| 01   | 赵雷  | 1990-01-01 00:00:00 ||
| 02   | 钱电  | 1990-12-21 00:00:00 ||
| 03   | 孙风  | 1990-12-20 00:00:00 ||
| 04   | 李云  | 1990-12-06 00:00:00 ||
| 05   | 周梅  | 1991-12-01 00:00:00 ||
| 06   | 吴兰  | 1992-01-01 00:00:00 ||
| 07   | 郑竹  | 1989-01-01 00:00:00 ||
+------+-------+---------------------+------+
7 rows in set (0.00 sec)mysql>

5.查询「李」姓老师的数量

mysql> select count(*)-> from teacher-> where tname like '李%';
+----------+
| count(*) |
+----------+
|        1 |
+----------+
1 row in set (0.00 sec)mysql>

6.查询学过「张三」老师授课的同学的信息

mysql> select student.* from student,teacher,course,sc-> where->     student.sid = sc.sid->     and course.cid=sc.cid->     and course.tid = teacher.tid->     and tname = '张三';
+------+-------+---------------------+------+
| SId  | Sname | Sage                | Ssex |
+------+-------+---------------------+------+
| 01   | 赵雷  | 1990-01-01 00:00:00 ||
| 02   | 钱电  | 1990-12-21 00:00:00 ||
| 03   | 孙风  | 1990-12-20 00:00:00 ||
| 04   | 李云  | 1990-12-06 00:00:00 ||
| 05   | 周梅  | 1991-12-01 00:00:00 ||
| 07   | 郑竹  | 1989-01-01 00:00:00 ||
+------+-------+---------------------+------+
6 rows in set (0.00 sec)mysql>

7.查询没有学全所有课程的同学的信息

mysql> select * from student-> where student.sid not in (->   select sc.sid from sc->   group by sc.sid->   having count(sc.cid)= (select count(cid) from course)-> );
+------+-------+---------------------+------+
| SId  | Sname | Sage                | Ssex |
+------+-------+---------------------+------+
| 05   | 周梅  | 1991-12-01 00:00:00 ||
| 06   | 吴兰  | 1992-01-01 00:00:00 ||
| 07   | 郑竹  | 1989-01-01 00:00:00 ||
| 09   | 张三  | 2017-12-20 00:00:00 ||
| 10   | 李四  | 2017-12-25 00:00:00 ||
| 11   | 李四  | 2012-06-06 00:00:00 ||
| 12   | 赵六  | 2013-06-13 00:00:00 ||
| 13   | 孙七  | 2014-06-01 00:00:00 ||
+------+-------+---------------------+------+
8 rows in set (0.00 sec)mysql>

8.查询至少有一门课与学号为" 01 "的同学所学相同的同学的信

mysql> select * from student-> where student.sid in (->     select sc.sid from sc->     where sc.cid in(->         select sc.cid from sc->         where sc.sid = '01'->     )-> );
+------+-------+---------------------+------+
| SId  | Sname | Sage                | Ssex |
+------+-------+---------------------+------+
| 01   | 赵雷  | 1990-01-01 00:00:00 ||
| 02   | 钱电  | 1990-12-21 00:00:00 ||
| 03   | 孙风  | 1990-12-20 00:00:00 ||
| 04   | 李云  | 1990-12-06 00:00:00 ||
| 05   | 周梅  | 1991-12-01 00:00:00 ||
| 06   | 吴兰  | 1992-01-01 00:00:00 ||
| 07   | 郑竹  | 1989-01-01 00:00:00 ||
+------+-------+---------------------+------+
7 rows in set (0.00 sec)mysql>

9.查询和" 01 "号的同学学习的课程 完全相同的其他同学的信息

10.查询没学过"张三"老师讲授的任一门课程的学生姓名

mysql> select * from student->     where student.sid not in(->         select sc.sid from sc where sc.cid in(->             select course.cid from course where course.tid in(->                 select teacher.tid from teacher where tname = "张三"->             )->         )->     );
+------+-------+---------------------+------+
| SId  | Sname | Sage                | Ssex |
+------+-------+---------------------+------+
| 06   | 吴兰  | 1992-01-01 00:00:00 ||
| 09   | 张三  | 2017-12-20 00:00:00 ||
| 10   | 李四  | 2017-12-25 00:00:00 ||
| 11   | 李四  | 2012-06-06 00:00:00 ||
| 12   | 赵六  | 2013-06-13 00:00:00 ||
| 13   | 孙七  | 2014-06-01 00:00:00 ||
+------+-------+---------------------+------+
6 rows in set (0.00 sec)mysql> select * from student-> where student.sid not in(->     select sc.sid from sc,course,teacher->     where->         sc.cid = course.cid->         and course.tid = teacher.tid->         and teacher.tname= "张三"-> );
+------+-------+---------------------+------+
| SId  | Sname | Sage                | Ssex |
+------+-------+---------------------+------+
| 06   | 吴兰  | 1992-01-01 00:00:00 ||
| 09   | 张三  | 2017-12-20 00:00:00 ||
| 10   | 李四  | 2017-12-25 00:00:00 ||
| 11   | 李四  | 2012-06-06 00:00:00 ||
| 12   | 赵六  | 2013-06-13 00:00:00 ||
| 13   | 孙七  | 2014-06-01 00:00:00 ||
+------+-------+---------------------+------+
6 rows in set (0.00 sec)mysql>

11.查询两门及其以上不及格课程的同学的学号,姓名及其平均成绩

mysql> select student.SId, student.Sname,b.avg-> from student RIGHT JOIN-> (select sid, AVG(score) as avg from sc->     where sid in (->               select sid from sc->               where score<60->               GROUP BY sid->               HAVING count(score)>1)->     GROUP BY sid) b on student.sid=b.sid;
+------+-------+----------+
| SId  | Sname | avg      |
+------+-------+----------+
| 04   | 李云  | 33.33333 |
| 06   | 吴兰  | 32.50000 |
+------+-------+----------+
2 rows in set (0.00 sec)mysql>

12.检索" 01 "课程分数小于 60,按分数降序排列的学生信息

mysql> select student.*, sc.score from student, sc-> where student.sid = sc.sid-> and sc.score < 60-> and cid = "01"-> ORDER BY sc.score DESC;
+------+-------+---------------------+------+-------+
| SId  | Sname | Sage                | Ssex | score |
+------+-------+---------------------+------+-------+
| 04   | 李云  | 1990-12-06 00:00:00 ||  50.0 |
| 06   | 吴兰  | 1992-01-01 00:00:00 ||  31.0 |
+------+-------+---------------------+------+-------+
2 rows in set (0.00 sec)mysql>

13.按平均成绩从高到低显示所有学生的所有课程的成绩以及平均成绩

mysql> select *  from sc-> left join (->     select sid,avg(score) as avscore from sc->     group by sid->     )r-> on sc.sid = r.sid-> order by avscore desc;
+------+------+-------+------+----------+
| SId  | CId  | score | sid  | avscore  |
+------+------+-------+------+----------+
| 07   | 02   |  89.0 | 07   | 93.50000 |
| 07   | 03   |  98.0 | 07   | 93.50000 |
| 01   | 01   |  80.0 | 01   | 89.66667 |
| 01   | 02   |  90.0 | 01   | 89.66667 |
| 01   | 03   |  99.0 | 01   | 89.66667 |
| 05   | 01   |  76.0 | 05   | 81.50000 |
| 05   | 02   |  87.0 | 05   | 81.50000 |
| 03   | 01   |  80.0 | 03   | 80.00000 |
| 03   | 02   |  80.0 | 03   | 80.00000 |
| 03   | 03   |  80.0 | 03   | 80.00000 |
| 02   | 01   |  70.0 | 02   | 70.00000 |
| 02   | 02   |  60.0 | 02   | 70.00000 |
| 02   | 03   |  80.0 | 02   | 70.00000 |
| 04   | 01   |  50.0 | 04   | 33.33333 |
| 04   | 02   |  30.0 | 04   | 33.33333 |
| 04   | 03   |  20.0 | 04   | 33.33333 |
| 06   | 01   |  31.0 | 06   | 32.50000 |
| 06   | 03   |  34.0 | 06   | 32.50000 |
+------+------+-------+------+----------+
18 rows in set (0.00 sec)mysql>

14.查询各科成绩最高分、最低分和平均分:

以如下形式显示:课程 ID,课程 name,最高分,最低分,平均分,及格率,中等率,优良率,优秀率
及格为>=60,中等为:70-80,优良为:80-90,优秀为:>=90
要求输出课程号和选修人数,查询结果按人数降序排列,若人数相同,按课程号升序排列

15.按各科成绩进行排序,并显示排名, Score 重复时保留名次空缺

15.1 按各科成绩进行排序,并显示排名, Score 重复时合并名次

16.查询学生的总成绩,并进行排名,总分重复时保留名次空缺

16.1 查询学生的总成绩,并进行排名,总分重复时不保留名次空缺

17.统计各科成绩各分数段人数:课程编号,课程名称,[100-85],[85-70],[70-60],[60-0] 及所占百分比

18.查询各科成绩前三名的记录

mysql> select * from sc-> where (-> select count(*) from sc as a-> where sc.cid = a.cid and sc.score<a.score-> )< 3-> order by cid asc, sc.score desc;
+------+------+-------+
| SId  | CId  | score |
+------+------+-------+
| 01   | 01   |  80.0 |
| 03   | 01   |  80.0 |
| 05   | 01   |  76.0 |
| 01   | 02   |  90.0 |
| 07   | 02   |  89.0 |
| 05   | 02   |  87.0 |
| 01   | 03   |  99.0 |
| 07   | 03   |  98.0 |
| 02   | 03   |  80.0 |
| 03   | 03   |  80.0 |
+------+------+-------+
10 rows in set (0.00 sec)mysql>

19.查询每门课程被选修的学生数

mysql> select cid, count(sid) from sc-> group by cid;
+------+------------+
| cid  | count(sid) |
+------+------------+
| 01   |          6 |
| 02   |          6 |
| 03   |          6 |
+------+------------+
3 rows in set (0.00 sec)mysql>

20.查询出只选修两门课程的学生学号和姓名

嵌套查询
mysql> select student.sid, student.sname from student-> where student.sid in-> (select sc.sid from sc-> group by sc.sid-> having count(sc.cid)=2-> );
+------+-------+
| sid  | sname |
+------+-------+
| 05   | 周梅  |
| 06   | 吴兰  |
| 07   | 郑竹  |
+------+-------+
3 rows in set (0.00 sec)

21.查询男生、女生人数

mysql> select ssex, count(*) from student-> group by ssex;
+------+----------+
| ssex | count(*) |
+------+----------+
||        4 |
||        8 |
+------+----------+
2 rows in set (0.00 sec)mysql>

22.查询名字中含有「风」字的学生信息

23.查询同名同性学生名单,并统计同名人数

mysql> select sname, count(*) from student-> group by sname-> having count(*)>1;
+-------+----------+
| sname | count(*) |
+-------+----------+
| 李四  |        2 |
+-------+----------+
1 row in set (0.00 sec)mysql> select * from student-> where sname in (-> select sname from student-> group by sname-> having count(*)>1-> );
+------+-------+---------------------+------+
| SId  | Sname | Sage                | Ssex |
+------+-------+---------------------+------+
| 10   | 李四  | 2017-12-25 00:00:00 ||
| 11   | 李四  | 2012-06-06 00:00:00 ||
+------+-------+---------------------+------+
2 rows in set (0.00 sec)mysql>

24.查询 1990 年出生的学生名单

mysql> select *-> from student-> where YEAR(student.Sage)=1990;
+------+-------+---------------------+------+
| SId  | Sname | Sage                | Ssex |
+------+-------+---------------------+------+
| 01   | 赵雷  | 1990-01-01 00:00:00 ||
| 02   | 钱电  | 1990-12-21 00:00:00 ||
| 03   | 孙风  | 1990-12-20 00:00:00 ||
| 04   | 李云  | 1990-12-06 00:00:00 ||
+------+-------+---------------------+------+
4 rows in set (0.00 sec)mysql>

25.查询每门课程的平均成绩,结果按平均成绩降序排列,平均成绩相同时,按课程编号升序排列

26.查询平均成绩大于等于 85 的所有学生的学号、姓名和平均成绩

27.查询课程名称为「数学」,且分数低于 60 的学生姓名和分数

mysql> select student.sname, sc.score from student, sc, course-> where student.sid = sc.sid-> and course.cid = sc.cid-> and course.cname = "数学"-> and sc.score < 60;
+-------+-------+
| sname | score |
+-------+-------+
| 李云  |  30.0 |
+-------+-------+
1 row in set (0.00 sec)mysql>

28.查询所有学生的课程及分数情况(存在学生没成绩,没选课的情况)

mysql> select student.sname, cid, score from student-> left join sc-> on student.sid = sc.sid;
+-------+------+-------+
| sname | cid  | score |
+-------+------+-------+
| 赵雷  | 03   |  99.0 |
| 赵雷  | 02   |  90.0 |
| 赵雷  | 01   |  80.0 |
| 钱电  | 03   |  80.0 |
| 钱电  | 02   |  60.0 |
| 钱电  | 01   |  70.0 |
| 孙风  | 03   |  80.0 |
| 孙风  | 02   |  80.0 |
| 孙风  | 01   |  80.0 |
| 李云  | 03   |  20.0 |
| 李云  | 02   |  30.0 |
| 李云  | 01   |  50.0 |
| 周梅  | 02   |  87.0 |
| 周梅  | 01   |  76.0 |
| 吴兰  | 03   |  34.0 |
| 吴兰  | 01   |  31.0 |
| 郑竹  | 03   |  98.0 |
| 郑竹  | 02   |  89.0 |
| 张三  | NULL |  NULL |
| 李四  | NULL |  NULL |
| 李四  | NULL |  NULL |
| 赵六  | NULL |  NULL |
| 孙七  | NULL |  NULL |
+-------+------+-------+
23 rows in set (0.00 sec)mysql>

29.查询任何一门课程成绩在 70 分以上的姓名、课程名称和分数

mysql> select student.sname, course.cname,sc.score from student,course,sc-> where sc.score>70-> and student.sid = sc.sid-> and sc.cid = course.cid;
+-------+-------+-------+
| sname | cname | score |
+-------+-------+-------+
| 赵雷  | 英语  |  99.0 |
| 赵雷  | 数学  |  90.0 |
| 赵雷  | 语文  |  80.0 |
| 钱电  | 英语  |  80.0 |
| 孙风  | 英语  |  80.0 |
| 孙风  | 数学  |  80.0 |
| 孙风  | 语文  |  80.0 |
| 周梅  | 数学  |  87.0 |
| 周梅  | 语文  |  76.0 |
| 郑竹  | 英语  |  98.0 |
| 郑竹  | 数学  |  89.0 |
+-------+-------+-------+
11 rows in set (0.00 sec)mysql>

30.查询不及格的课程

mysql> select cid from sc-> where score< 60-> group by cid;
+------+
| cid  |
+------+
| 01   |
| 02   |
| 03   |
+------+
3 rows in set (0.00 sec)mysql> select DISTINCT sc.CId-> from sc-> where sc.score <60;
+------+
| CId  |
+------+
| 01   |
| 02   |
| 03   |
+------+
3 rows in set (0.00 sec)mysql>

31.查询课程编号为 01 且课程成绩在 80 分以上的学生的学号和姓名

mysql> select student.sid,student.sname-> from student,sc-> where cid="01"-> and score>=80-> and student.sid = sc.sid;
+------+-------+
| sid  | sname |
+------+-------+
| 01   | 赵雷  |
| 03   | 孙风  |
+------+-------+
2 rows in set (0.00 sec)mysql>

32.求每门课程的学生人数

mysql> select sc.CId,count(*) as 学生人数-> from sc-> GROUP BY sc.CId;
+------+----------+
| CId  | 学生人数 |
+------+----------+
| 01   |        6 |
| 02   |        6 |
| 03   |        6 |
+------+----------+
3 rows in set (0.00 sec)mysql>

33.成绩不重复,查询选修「张三」老师所授课程的学生中,成绩最高的学生信息及其成绩

34.成绩有重复的情况下,查询选修「张三」老师所授课程的学生中,成绩最高的学生信息及其成绩

mysql> select student.*, sc.score, sc.cid from student, teacher, course,sc-> where teacher.tid = course.tid-> and sc.sid = student.sid-> and sc.cid = course.cid-> and teacher.tname = "张三"-> and sc.score = (->     select Max(sc.score)->     from sc,student, teacher, course->     where teacher.tid = course.tid->     and sc.sid = student.sid->     and sc.cid = course.cid->     and teacher.tname = "张三"-> );
+------+-------+---------------------+------+-------+------+
| SId  | Sname | Sage                | Ssex | score | cid  |
+------+-------+---------------------+------+-------+------+
| 01   | 赵雷  | 1990-01-01 00:00:00 ||  90.0 | 02   |
| 07   | 郑竹  | 1989-01-01 00:00:00 ||  90.0 | 02   |
+------+-------+---------------------+------+-------+------+
2 rows in set (0.00 sec)mysql>

35.查询不同课程成绩相同的学生的学生编号、课程编号、学生成绩

36.查询每门功成绩最好的前两名

37.统计每门课程的学生选修人数(超过 5 人的课程才统计)。

mysql> select sc.cid, count(sid) as cc from sc-> group by cid-> having cc >5;
+------+----+
| cid  | cc |
+------+----+
| 01   |  6 |
| 02   |  6 |
| 03   |  6 |
+------+----+
3 rows in set (0.00 sec)mysql>

38.检索至少选修两门课程的学生学号

mysql> select sid, count(cid) as cc from sc-> group by sid-> having cc>=2;
+------+----+
| sid  | cc |
+------+----+
| 01   |  3 |
| 02   |  3 |
| 03   |  3 |
| 04   |  3 |
| 05   |  2 |
| 06   |  2 |
| 07   |  2 |
+------+----+
7 rows in set (0.00 sec)mysql>

39.查询选修了全部课程的学生信息

40.查询各学生的年龄,只按年份来算

41.按照出生日期来算,当前月日 < 出生年月的月日则,年龄减一

42.查询本周过生日的学生

43.查询下周过生日的学生

44.查询本月过生日的学生

mysql> select *-> from student-> where MONTH(student.Sage)=MONTH(CURDATE());
+------+-------+---------------------+------+
| SId  | Sname | Sage                | Ssex |
+------+-------+---------------------+------+
| 01   | 赵雷  | 1990-01-01 00:00:00 ||
| 06   | 吴兰  | 1992-01-01 00:00:00 ||
| 07   | 郑竹  | 1989-01-01 00:00:00 ||
+------+-------+---------------------+------+
3 rows in set (0.00 sec)

45.查询下月过生日的学生

本文来自互联网用户投稿,该文观点仅代表作者本人,不代表本站立场。本站仅提供信息存储空间服务,不拥有所有权,不承担相关法律责任。如若转载,请注明出处:http://www.mzph.cn/news/635555.shtml

如若内容造成侵权/违法违规/事实不符,请联系多彩编程网进行投诉反馈email:809451989@qq.com,一经查实,立即删除!

相关文章

2024年阿里云优惠券和代金券领取,活动整理服务器价格表

2024阿里云优惠活动&#xff0c;免费领取阿里云优惠代金券&#xff0c;阿里云优惠活动大全和云服务器优惠价格表&#xff0c;阿里云ECS服务器优惠价99元一年起&#xff0c;轻量服务器优惠价61元一年&#xff0c;阿里云服务器网aliyunfuwuqi.com分享阿里云优惠券免费领取、优惠活…

智能数据采集网关如何助力制造企业生产提效

随着工业4.0的推进&#xff0c;制造业正面临着一场数据革命。某高端制造企业为了提高生产效率、降低运营成本&#xff0c;决定引入智能数据采集网关&#xff0c;以实现生产过程的智能化管理。 该高端制造企业主要从事精密机械零件的生产。在传统生产模式下&#xff0c;生产过程…

Python算法题集_字母异位词分组

本文为Python算法题集之一的代码示例 题目49&#xff1a;字母异位词分组 说明&#xff1a;给你一个字符串数组&#xff0c;请你将 字母异位词 组合在一起&#xff0c;可以按任意顺序返回结果列表 字母异位词 &#xff1a;是由重新排列原单词所有字母得到的新单词 使用同步数…

GCC 内联汇编

LINUX下的汇编入门 AT&T风格 汇编 和GCC风格汇编 汇编代码的调试 前面写了三篇,是自我摸索三篇,摸着石头过河,有些或许是错误的细节,不必在意! 今天我们直接用GCC编译C语言代码,且在C语言里面内嵌AT&T风格的汇编! 前三篇大家了解即可,我们重点放在内嵌汇编里,简单快…

Java设计模式-单例模式(2)

大家好&#xff0c;我是馆长&#xff01;从今天开始馆长开始对java设计模式的创建型模式中的单例、原型、工厂方法、抽象工厂、建造者的单例模式进行讲解和说明。 单例模式&#xff08;Singleton&#xff09; 定义 某个类只能生成一个实例&#xff0c;该类提供了一个全局访问…

AI如何助力制造业变革?

当前&#xff0c;制造业企业正在转型发展&#xff0c;发力智能制造&#xff0c;以实现降低成本、提高效率和提高客户满意度的目标。这其中人工智能&#xff08;AI&#xff09;被认为是最重要的一项技术。AI技术可以优化制造流程&#xff0c;大大提高生产力&#xff0c;帮助企业…

houdini rnn

1.3.RNN模型_哔哩哔哩_bilibili 此公式来自于吴恩达P1.3视频 按公式推测rnn内部结构,如有错误&#xff0c;敬请指正

【话题】边缘计算的挑战和机遇

边缘计算是一种新的计算范式&#xff0c;其核心是在网络边缘处理数据&#xff0c;而不是传统的中心式云计算模式。这种计算方式的兴起得益于物联网&#xff08;IoT&#xff09;的普及和丰富的云服务的成功。 机遇&#xff1a; 响应时间优化&#xff1a;由于数据处理更接近数据…

解决系统开发中的跨域问题:CORS、JSONP、Nginx

文章目录 一、概述1.问题场景2.浏览器的同源策略3.解决思路 二、一点准备工作1.创建前端工程12.创建后端工程3.创建前端工程24.跨域问题 三、方法1&#xff1a;使用CORS四、方法2&#xff1a;JSONP五、方法3&#xff1a;Nginx1.安装和启动&#xff08;windows&#xff09;2.使用…

初识VUE

文章目录 Vue是什么1.创建一个Vue实例2.插值表达式{{ }}3.Vue的响应式特性4.开发者工具的安装 Vue是什么 概念&#xff1a;Vue是一个用于构建用户界面的渐进式框架 ①构建用户界面&#xff1a;基于数据渲染出用户看到的界面 ②渐进式&#xff1a;循序渐进 ③ 框架&#xff1…

Flask用于生产环境

Flask是一个用Python编写的轻量级Web应用框架&#xff0c;可以用于开发和部署Web服务。要安装Flask&#xff0c;您需要以下步骤&#xff1a; - 安装Python和pip&#xff0c;如果您还没有的话。 - 创建一个虚拟环境&#xff0c;以便隔离您的Flask应用程序和其他Python项目。 - …

MySQL经典面试题

目录 1、查询课程名称为“数据库”&#xff0c;且分数低于60分的学生姓名和分数 2、对所有性别为“女”的学生&#xff0c;同时课程名为“高等数学”的分数统一加5 3、删除姓名为“张翰”&#xff08;学号1&#xff09;课程名为“数据库”的课程成绩 4、统计2021年11月每天…

6.4.4释放音频

6.4.4释放音频 许多Flash动画里的音乐或歌曲非常好听&#xff0c;能不能在没有源文件的情况下把里面的声音文件取出来呢&#xff1f;利用Swf2VideoConverter2可以轻松做到这一点。 1&#xff0e;单击“添加”按钮&#xff0c;在弹出的下拉菜单中选择“添加文件”&#xff0c;…

金蝶云星空表单插件获取单据体数据

文章目录 金蝶云星空表单插件获取单据体数据 金蝶云星空表单插件获取单据体数据 使用标识报错 var thisEntry this.View.Model.DataObject["FEntity"] as DynamicObjectCollection;应该使用实体属性 var thisEntry this.View.Model.DataObject["BillEntry&q…

搜索经典题——填充 9*9矩阵

题目&#xff1a;给定一个九行九列矩阵&#xff0c;填充矩阵元素&#xff0c;要求&#xff1a; 1、每一行每一列&#xff0c;每个小九宫格&#xff08;图片画粗的地方就是&#xff09;不能包含相同元素 2、每一行&#xff0c;每一列&#xff0c;每个小九宫格均会完整出现1-9的数…

面试题目,你对前端工程化的了解

前端工程化是通过工具和流程来提高软件开发效率、降低维护成本以及改善项目可维护性的方法。在前端领域&#xff0c;前端工程化通常包括以下方面内容 版本控制 使用 git 来管理代码的版本&#xff0c;追踪变更&#xff0c;协作开发等项目脚手架 使用项目的脚手架进行项目的初始…

【Python爬虫】项目案例讲解,一步步教你爬取淘宝商品数据!

前言 随着互联网时代的到来&#xff0c;人们更加倾向于互联网购物&#xff0c;某宝又是电商行业的巨头&#xff0c;在某宝平台中有很多商家数据&#xff0c;今天带大家使用pythonselenium工具获取这些公开的商家数据 环境介绍&#xff1a; python 3.6pycharmseleniumcsvtime…

SpringBoot自动装配原理及分析

一、什么是自动装配 在使用SpringBoot的时候&#xff0c;会自动将Bean装配到IOC容器中。例如我们在使用Redis数据库的时候&#xff0c;会引入依赖spring-boot-starter-data-redis。在引入这个依赖后&#xff0c;服务初始化的时候&#xff0c;会将操作Redis需要的组件注入到Ioc…

vue3 项目中 arguments 对象获取失败问题

问题 在 vue3 项目中 获取到的 arguments 对象与传入实参不符&#xff0c;打印出函数中的 arguments 对象显示如下&#xff1a; 原因 作者仔细回看代码才发现&#xff0c;自己一直用的是 vue3 的组合式写法&#xff0c;函数都是箭头函数&#xff0c;而箭头函数不存在 argumen…

故障诊断传感器的位置会影响振动信号分类的精度吗?

问题描述&#xff1a;故障诊断传感器的位置会影响振动信号分类的精度吗&#xff1f; 问题解答&#xff1a; 是的&#xff0c;故障诊断中传感器的位置确实可能会影响振动信号分类的精度。 首先&#xff0c;传感器的位置决定了能够采集到的振动信号的特性。如果传感器靠近故障…