编写一个JDBC程序,要求如下: 1)查询user表数据进行操作,表设计可参考11.3.2节表 2)使用JDBC分别完成数据的插入、修改、查询和删除操作
时间: 2023-07-15 14:12:23 浏览: 52
以下是一个简单的JDBC程序,满足您的需求:
```java
import java.sql.*;
public class JDBCExample {
static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
static final String DB_URL = "jdbc:mysql://localhost:3306/mydatabase";
static final String USERNAME = "root";
static final String PASSWORD = "password";
public static void main(String[] args) {
Connection conn = null;
Statement stmt = null;
try {
// 注册 JDBC 驱动器
Class.forName(JDBC_DRIVER);
// 打开一个连接
System.out.println("连接到数据库...");
conn = DriverManager.getConnection(DB_URL, USERNAME, PASSWORD);
// 执行查询
System.out.println("创建查询语句...");
stmt = conn.createStatement();
String sql = "SELECT * FROM user";
ResultSet rs = stmt.executeQuery(sql);
// 输出结果
while (rs.next()) {
int id = rs.getInt("id");
String name = rs.getString("name");
String email = rs.getString("email");
System.out.println("ID: " + id + ", Name: " + name + ", Email: " + email);
}
// 插入数据
System.out.println("插入数据...");
sql = "INSERT INTO user VALUES (4, 'Mike', 'mike@example.com')";
int rows = stmt.executeUpdate(sql);
System.out.println(rows + " 行被插入。");
// 修改数据
System.out.println("修改数据...");
sql = "UPDATE user SET email='john@example.com' WHERE name='John'";
rows = stmt.executeUpdate(sql);
System.out.println(rows + " 行