学生信息管理系统内容：
学生表student(Sno,Sname,Ssex,Sage,Sdept)
课程表course(Cno,Cname,Cpno,Ccredit)
学生选课表SC(Sno,Cno,Grade)
一、 创建数据库并使用
mysql> use dx;
Database changed
二、 创建数据库表并显示数据课表结构
学生选课表SC(Sno,Cno,Grade)
mysql> create table SC
-> (Sno varchar(255),
-> Cno varchar(255),
-> Grade smallint
-> );
Query OK, 0 rows affected (0.06 sec)
mysql> desc sc;
+-------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+--------------+------+-----+---------+-------+
| Sno | varchar(255) | YES | | NULL | |
| Cno | varchar(255) | YES | | NULL | |
| Grade | smallint(6) | YES | | NULL | |
+-------+--------------+------+-----+---------+-------+
3 rows in set (0.05 sec)
mysql>
学生表student(Sno,Sname,Ssex,Sage,Sdept)
mysql> create table student(Sno varchar(255),Sname varchar(255),Sage int,Sdept varchar(255));
Query OK, 0 rows affected (0.08 sec)
mysql> desc student;
+-------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+--------------+------+-----+---------+-------+
| Sno | varchar(255) | YES | | NULL | |
| Sname | varchar(255) | YES | | NULL | |
| Sage | int(11) | YES | | NULL | |
| Sdept | varchar(255) | YES | | NULL | |
+-------+--------------+------+-----+---------+-------+
4 rows in set (0.01 sec)
mysql>
课程表course(Cno,Cname,Cpno,Ccredit)
mysql> create table course(Cno varchar(255),Cname varchar(255),Cpno int,Ccredit varchar(255));
Query OK, 0 rows affected (0.09 sec)
mysql> desc course;
+---------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------+--------------+------+-----+---------+-------+
| Cno | varchar(255) | YES | | NULL | |
| Cname | varchar(255) | YES | | NULL | |
| Cpno | int(11) | YES | | NULL | |
| Ccredit | varchar(255) | YES | | NULL | |
+---------+--------------+------+-----+---------+-------+
4 rows in set (0.01 sec)
显示数据库中是数据库表：
mysql> show tables;
+--------------+
| Tables_in_dx |
+--------------+
| course |
| sc |
| student |
+--------------+
3 rows in set (0.00 sec)
三、 在数据库表中插入数据
在数据库表SC中插入数据：
mysql> insert into SC values('20161018','1',90);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('20161019','2',90);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('20161020','3',100);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SC values('20161021','4',89);
Query OK, 1 row affected (0.00 sec)
mysql> select * from SC;
+----------+------+-------+
| Sno | Cno | Grade |
+----------+------+-------+
| 20161018 | 1 | 90 |
| 20161019 | 2 | 90 |
| 20161020 | 3 | 100 |
| 20161021 | 4 | 89 |
+----------+------+-------+
4 rows in set (0.00 sec)
其他数据库表插入数据也一样，不过需要注意的是变量的形式（字符型、整型、浮点数）
mysql> select * from student;
+----------+-------+------+------+-------+
| Sno | Sname | Ssex | Sage | Sdept |
+----------+-------+------+------+-------+
| 20161018 | 里勇 | 男 | 20 | CS |
| 20161019 | 刘成 | 女 | 19 | IS |
| 20161020 | 王敏 | 女 | 19 | MA |
| 20161021 | 张里 | 男 | 18 | MA |
+----------+-------+------+------+-------+
4 rows in set (0.00 sec)
mysql> select Sno,Sname from student;
+----------+-------+
| Sno | Sname |
+----------+-------+
| 20161018 | 里勇 |
| 20161019 | 刘成 |
| 20161020 | 王敏 |
| 20161021 | 张里 |
+----------+-------+
4 rows in set (0.00 sec)
mysql> select Sname,2016-Sage from student;
+-------+-----------+
| Sname | 2016-Sage |
+-------+-----------+
| 里勇 | 1996 |
| 刘成 | 1997 |
| 王敏 | 1997 |
| 张里 | 1998 |
+-------+-----------+
4 rows in set (0.00 sec)
mysql> select * from course;
+-----+----------+------+---------+
| Cno | Cname | Cpno | Ccredit |
+-----+----------+------+---------+
| 1 | 高数 | 1 | 6 |
| 2 | 大物 | 2 | 4 |
| 3 | 数电 | 3 | 6 |
| 4 | 大学英语 | 4 | 5 |
| 5 | 数据库 | 5 | 3 |
+-----+----------+------+---------+
5 rows in set (0.04 sec)
四、将数据库表进行改名
mysql> select Sname as 姓名,'Year of Birth:',2016-Sage 出生年份,lower(Sdept) 学院 from student;
+------+----------------+----------+------+
| 姓名 | Year of Birth: | 出生年份 | 学院 |
+------+----------------+----------+------+
| 里勇 | Year of Birth: | 1996 | cs |
| 刘成 | Year of Birth: | 1997 | is |
| 王敏 | Year of Birth: | 1997 | ma |
| 张里 | Year of Birth: | 1998 | ma |
+------+----------------+----------+------+
4 rows in set (0.00 sec)
五、 对数据库表进行各种操作
mysql> select Sno from SC;
+----------+
| Sno |
+----------+
| 20161018 |
| 20161019 |
| 20161020 |
| 20161021 |
+----------+
4 rows in set (0.00 sec)
mysql> select distinct Grade from SC;
+-------+
| Grade |
+-------+
| 90 |
| 100 |
| 89 |
+-------+
3 rows in set (0.00 sec)
mysql> select distinct Sno from SC where Grade > 90;
+----------+
| Sno |
+----------+
| 20161020 |
+----------+
1 row in set (0.00 sec)
mysql> select Sname,Ssex
-> from student
-> where Sdept = 'IS' or Sdept = 'MA' or Sdept = 'CS';
+-------+------+
| Sname | Ssex |
+-------+------+
| 里勇 | 男 |
| 刘成 | 女 |
| 王敏 | 女 |
| 张里 | 男 |
+-------+------+
4 rows in set (0.00 sec)
mysql> select count(*) from student;
+----------+
| count(*) |
+----------+
| 4 |
+----------+
1 row in set (0.00 sec)
mysql> select avg(Grade) from SC;
+------------+
| avg(Grade) |
+------------+
| 92.2500 |
+------------+
1 row in set (0.00 sec)
mysql> select Cno,count(Sno)
-> from SC
-> group by Cno;
+------+------------+
| Cno | count(Sno) |
+------+------------+
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
+------+------------+
4 rows in set (0.00 sec)
mysql> select Cno,avg(Grade)
-> from SC
-> group by Cno;
+------+------------+
| Cno | avg(Grade) |
+------+------------+
| 1 | 90.0000 |
| 2 | 90.0000 |
| 3 | 100.0000 |
| 4 | 89.0000 |
+------+------------+
4 rows in set (0.00 sec)
mysql> select student.*,sc.*
-> from student,sc
-> where student.Sno = sc.Sno;
+----------+-------+------+------+-------+----------+------+-------+
| Sno | Sname | Ssex | Sage | Sdept | Sno | Cno | Grade |
+----------+-------+------+------+-------+----------+------+-------+
| 20161018 | 里勇 | 男 | 20 | CS | 20161018 | 1 | 90 |
| 20161019 | 刘成 | 女 | 19 | IS | 20161019 | 2 | 90 |
| 20161020 | 王敏 | 女 | 19 | MA | 20161020 | 3 | 100 |
| 20161021 | 张里 | 男 | 18 | MA | 20161021 | 4 | 89 |
+----------+-------+------+------+-------+----------+------+-------+
4 rows in set (0.00 sec)
mysql> select student.Sno,Sname,Ssex,Sage,Sdept,Cno,Grade
-> from student,sc
-> where student.Sno = sc.Sno;
+----------+-------+------+------+-------+------+-------+
| Sno | Sname | Ssex | Sage | Sdept | Cno | Grade |
+----------+-------+------+------+-------+------+-------+
| 20161018 | 里勇 | 男 | 20 | CS | 1 | 90 |
| 20161019 | 刘成 | 女 | 19 | IS | 2 | 90 |
| 20161020 | 王敏 | 女 | 19 | MA | 3 | 100 |
| 20161021 | 张里 | 男 | 18 | MA | 4 | 89 |
+----------+-------+------+------+-------+------+-------+
4 rows in set (0.00 sec)
mysql> select student.Sno,Sname,Cname,Grade
-> from student,sc,course
-> where student.Sno = sc.Sno and sc.Cno = course.Cno;
+----------+-------+----------+-------+
| Sno | Sname | Cname | Grade |
+----------+-------+----------+-------+
| 20161018 | 里勇 | 高数 | 90 |
| 20161019 | 刘成 | 大物 | 90 |
| 20161020 | 王敏 | 数电 | 100 |
| 20161021 | 张里 | 大学英语 | 89 |
+----------+-------+----------+-------+
4 rows in set (0.00 sec)
mysql>
这篇博文主要是利用数据库对学生信息进行管理，它可以利用各种操作对学生信息进行增删减查，非常的方便！！！
当然最重要的是你自己动手去做，不然一切免谈，也不要指望着别人。。。嘻嘻嘻。。。送我个赞呗。。。
各位老铁们，给我个三连击呗，可以让更多的人看到这篇文章，同时也激励一下我
各位老铁们，给我个三连击呗，可以让更多的人看到这篇文章，同时也激励一下我
各位老铁们，给我个三连击呗，可以让更多的人看到这篇文章，同时也激励一下我
原创文章 58
获赞 115
访问量 1万+