使用prepareStatement连接数据库实现增、删、改、查

时间:2022-07-28
本文章向大家介绍使用prepareStatement连接数据库实现增、删、改、查,主要内容包括其使用实例、应用技巧、基本知识点总结和需要注意事项,具有一定的参考价值,需要的朋友可以参考一下。

一、代码

自己建的数据库表如下图:

package d03_system;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

/**
 * zt
 * 2020/8/20
 * 15:05
 * 使用prepareStatement实现增、删、改、查
 */
public class JdbcDemo5 {
    public static void main(String[] args) throws Exception {
        //1.注册驱动
        Class.forName("com.mysql.jdbc.Driver");
        //2.创建链接
        Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/gp2002?useSSL=false&characterEncoding=utf8", "root", "root");
        //3.创建命令
        PreparedStatement pstat = conn.prepareStatement("insert into user(name,password) values (?,?)");
        //4.参数赋值
        /*pstat.setString(1, "萧炎");
        pstat.setString(2, "123");
        //5.执行
        int i = pstat.executeUpdate();
        System.out.println("执行结果(~ ̄▽ ̄)~ :"+i);*/

        //循环添加数据
        /*for (int i = 0; i < 10; i++) {
            pstat.setString(1, "萧炎"+i);
            pstat.setString(2, "123");
            int i1 = pstat.executeUpdate();
            System.out.println("执行结果(~ ̄▽ ̄)~ :"+i1);
        }*/

        //删除
        /*PreparedStatement pstat2 = conn.prepareStatement("delete from user where id>=?");
        pstat2.setInt(1, 6);
        int i3 = pstat2.executeUpdate();
        System.out.println("执行结果(~ ̄▽ ̄)~ :"+i3);*/

        //更新
        /*PreparedStatement pstat3 = conn.prepareStatement("update user set password='1234' where id = ?");
        pstat3.setInt(1, 3);
        int i4 = pstat3.executeUpdate();
        System.out.println("执行结果(~ ̄▽ ̄)~ :"+i4);*/

        //查询
        PreparedStatement pstat4 = conn.prepareStatement("select id,name,password from user");
        ResultSet rs = pstat4.executeQuery();
        while(rs.next()){
            int id = rs.getInt("id");
            String name = rs.getString("name");
            String password = rs.getString("password");
            System.out.println(id+"..."+name+"..."+password+"...");
        }


        //6.关闭
        pstat.close();
        conn.close();


    }
}

二、运行结果

1...大明...123...
2...夏雨荷...123...
3...萧炎...1234...
4...萧炎...123...
5...萧炎0...123...

Process finished with exit code 0