jdbc链接数据库

package itheima;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;

public class jdbcdemo {
    public static void main(String[] args) throws Exception {

        //1.注册驱动
        Class.forName("com.mysql.cj.jdbc.Driver");

        //2.获取链接
        String url="jdbc:mysql://localhost:3306/db1?useSSL=false&serverTimezone=UTC";
        String username="root";
        String password="123456789";
        Connection conn = DriverManager.getConnection(url, username, password);

        //定义sql语句
        String sql = "update account set money = 3000 where id=1";

        //4.获取sql执行的对象 Statement
        Statement stmt = conn.createStatement();
        
        //执行sql
        int count = stmt.executeUpdate(sql);//受影响的行数

        //处理结果
        System.out.println(count);

        //释放资源
        stmt.close();
        conn.close();
    }
}