网站建设结课总结,明光市建设局网站,网站建设中期怎么入账,免费咨询电脑维修数据表综合练习 题目#xff1a;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 n… 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 | 男 |
| 02 | 钱电 | 1990-12-21 00:00:00 | 男 |
| 03 | 孙风 | 1990-12-20 00:00:00 | 男 |
| 04 | 李云 | 1990-12-06 00:00:00 | 男 |
| 05 | 周梅 | 1991-12-01 00:00:00 | 女 |
| 06 | 吴兰 | 1992-01-01 00:00:00 | 女 |
| 07 | 郑竹 | 1989-01-01 00:00:00 | 女 |
| 09 | 张三 | 2017-12-20 00:00:00 | 女 |
| 10 | 李四 | 2017-12-25 00:00:00 | 女 |
| 11 | 李四 | 2012-06-06 00:00:00 | 女 |
| 12 | 赵六 | 2013-06-13 00:00:00 | 女 |
| 13 | 孙七 | 2014-06-01 00:00:00 | 女 |
----------------------------------------
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 | 男 | 02 | 70.0 | 60.0 |
| 04 | 李云 | 1990-12-06 00:00:00 | 男 | 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 | 男 |
| 04 | 50.0 | 30.0 | 04 | 李云 | 1990-12-06 00:00:00 | 男 |
--------------------------------------------------------------
2 rows in set (0.00 sec)mysql1.1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)mysql1.2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)mysql1.3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)mysql2.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)mysql3.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)mysql4.1 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 | 男 |
| 02 | 钱电 | 1990-12-21 00:00:00 | 男 |
| 03 | 孙风 | 1990-12-20 00:00:00 | 男 |
| 04 | 李云 | 1990-12-06 00:00:00 | 男 |
| 05 | 周梅 | 1991-12-01 00:00:00 | 女 |
| 06 | 吴兰 | 1992-01-01 00:00:00 | 女 |
| 07 | 郑竹 | 1989-01-01 00:00:00 | 女 |
----------------------------------------
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 | 男 |
| 02 | 钱电 | 1990-12-21 00:00:00 | 男 |
| 03 | 孙风 | 1990-12-20 00:00:00 | 男 |
| 04 | 李云 | 1990-12-06 00:00:00 | 男 |
| 05 | 周梅 | 1991-12-01 00:00:00 | 女 |
| 06 | 吴兰 | 1992-01-01 00:00:00 | 女 |
| 07 | 郑竹 | 1989-01-01 00:00:00 | 女 |
----------------------------------------
7 rows in set (0.00 sec)mysql5.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)mysql6.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.cidsc.cid- and course.tid teacher.tid- and tname 张三;
----------------------------------------
| SId | Sname | Sage | Ssex |
----------------------------------------
| 01 | 赵雷 | 1990-01-01 00:00:00 | 男 |
| 02 | 钱电 | 1990-12-21 00:00:00 | 男 |
| 03 | 孙风 | 1990-12-20 00:00:00 | 男 |
| 04 | 李云 | 1990-12-06 00:00:00 | 男 |
| 05 | 周梅 | 1991-12-01 00:00:00 | 女 |
| 07 | 郑竹 | 1989-01-01 00:00:00 | 女 |
----------------------------------------
6 rows in set (0.00 sec)mysql7.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 | 女 |
| 06 | 吴兰 | 1992-01-01 00:00:00 | 女 |
| 07 | 郑竹 | 1989-01-01 00:00:00 | 女 |
| 09 | 张三 | 2017-12-20 00:00:00 | 女 |
| 10 | 李四 | 2017-12-25 00:00:00 | 女 |
| 11 | 李四 | 2012-06-06 00:00:00 | 女 |
| 12 | 赵六 | 2013-06-13 00:00:00 | 女 |
| 13 | 孙七 | 2014-06-01 00:00:00 | 女 |
----------------------------------------
8 rows in set (0.00 sec)mysql8.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 | 男 |
| 02 | 钱电 | 1990-12-21 00:00:00 | 男 |
| 03 | 孙风 | 1990-12-20 00:00:00 | 男 |
| 04 | 李云 | 1990-12-06 00:00:00 | 男 |
| 05 | 周梅 | 1991-12-01 00:00:00 | 女 |
| 06 | 吴兰 | 1992-01-01 00:00:00 | 女 |
| 07 | 郑竹 | 1989-01-01 00:00:00 | 女 |
----------------------------------------
7 rows in set (0.00 sec)mysql9.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 | 女 |
| 09 | 张三 | 2017-12-20 00:00:00 | 女 |
| 10 | 李四 | 2017-12-25 00:00:00 | 女 |
| 11 | 李四 | 2012-06-06 00:00:00 | 女 |
| 12 | 赵六 | 2013-06-13 00:00:00 | 女 |
| 13 | 孙七 | 2014-06-01 00:00:00 | 女 |
----------------------------------------
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 | 女 |
| 09 | 张三 | 2017-12-20 00:00:00 | 女 |
| 10 | 李四 | 2017-12-25 00:00:00 | 女 |
| 11 | 李四 | 2012-06-06 00:00:00 | 女 |
| 12 | 赵六 | 2013-06-13 00:00:00 | 女 |
| 13 | 孙七 | 2014-06-01 00:00:00 | 女 |
----------------------------------------
6 rows in set (0.00 sec)mysql11.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 score60- GROUP BY sid- HAVING count(score)1)- GROUP BY sid) b on student.sidb.sid;
-----------------------
| SId | Sname | avg |
-----------------------
| 04 | 李云 | 33.33333 |
| 06 | 吴兰 | 32.50000 |
-----------------------
2 rows in set (0.00 sec)mysql12.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 | 男 | 50.0 |
| 06 | 吴兰 | 1992-01-01 00:00:00 | 女 | 31.0 |
-----------------------------------------------
2 rows in set (0.00 sec)mysql13.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)mysql14.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.scorea.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)mysql19.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)mysql20.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(*) |
----------------
| 男 | 4 |
| 女 | 8 |
----------------
2 rows in set (0.00 sec)mysql22.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 | 女 |
| 11 | 李四 | 2012-06-06 00:00:00 | 女 |
----------------------------------------
2 rows in set (0.00 sec)mysql24.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 | 男 |
| 02 | 钱电 | 1990-12-21 00:00:00 | 男 |
| 03 | 孙风 | 1990-12-20 00:00:00 | 男 |
| 04 | 李云 | 1990-12-06 00:00:00 | 男 |
----------------------------------------
4 rows in set (0.00 sec)mysql25.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)mysql28.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)mysql29.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.score70- 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)mysql30.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)mysql31.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 cid01- and score80- and student.sid sc.sid;
-------------
| sid | sname |
-------------
| 01 | 赵雷 |
| 03 | 孙风 |
-------------
2 rows in set (0.00 sec)mysql32.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)mysql33.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 | 男 | 90.0 | 02 |
| 07 | 郑竹 | 1989-01-01 00:00:00 | 女 | 90.0 | 02 |
-----------------------------------------------------
2 rows in set (0.00 sec)mysql35.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)mysql38.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 cc2;
----------
| sid | cc |
----------
| 01 | 3 |
| 02 | 3 |
| 03 | 3 |
| 04 | 3 |
| 05 | 2 |
| 06 | 2 |
| 07 | 2 |
----------
7 rows in set (0.00 sec)mysql39.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 | 男 |
| 06 | 吴兰 | 1992-01-01 00:00:00 | 女 |
| 07 | 郑竹 | 1989-01-01 00:00:00 | 女 |
----------------------------------------
3 rows in set (0.00 sec)45.查询下月过生日的学生
