以学生-课程数据库为例,使用SQL语言实现数据库的查看、创建、修改、删除、选择等操作
时间: 2024-12-23 17:23:31 浏览: 40
在以学生-课程数据库为例,我们可以使用SQL(Structured Query Language)来操作数据。以下是针对基本操作的一些SQL语句:
1. **创建表(Create Table)**:
```sql
CREATE TABLE Students (
ID INT PRIMARY KEY,
Name VARCHAR(50),
Age INT
);
CREATE TABLE Courses (
ID INT PRIMARY KEY,
CourseName VARCHAR(50),
Teacher VARCHAR(50)
);
```
2. **插入数据(Insert Data)**:
```sql
INSERT INTO Students (ID, Name, Age) VALUES (1, '张三', 18);
INSERT INTO Courses (ID, CourseName, Teacher) VALUES (1, '数学', '李老师');
```
3. **查询数据(Select Data)**:
- 查看所有学生信息:
```sql
SELECT * FROM Students;
```
- 按条件查询特定课程的学生:
```sql
SELECT Students.Name FROM Students JOIN Courses ON Students.ID = Courses.Student_ID WHERE Courses.CourseName = '数学';
```
4. **更新数据(Update Data)**:
```sql
UPDATE Students SET Age = 19 WHERE Name = '张三';
```
5. **删除数据(Delete Data)**:
```sql
DELETE FROM Students WHERE ID = 1;
```
6. **连接操作(Joins)**:
如果有学生选课关系表 `Enrollments`,可以做如下关联查询:
```sql
SELECT Students.Name, Courses.CourseName
FROM Students
JOIN Enrollments ON Students.ID = Enrollments.Student_ID
JOIN Courses ON Courses.ID = Enrollments.Course_ID;
```
以上就是使用SQL对这类数据库进行基本操作的例子。
阅读全文