03jdbc的crud练习

//添加
package cn.itcast.jdbc;

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

/**

• account表 添加一条记录 insert 语句

*/
public class JDBCDemo2 {

public static void main(String[] args) {    Statement stmt = null;//放到try内部就是局部变量    Connection conn = null;    try {        //1. 注册驱动        Class.forName("com.mysql.jdbc.Driver");        //2. 定义sql        String sql = "insert into account values(null,'王五',3000)";        //3.获取Connection对象        conn = DriverManager.getConnection("jdbc:mysql:///db3", "root", "root");        //4.获取执行sql的对象 Statement        stmt = conn.createStatement();        //5.执行sql        int count = stmt.executeUpdate(sql);//影响的行数        //6.处理结果        System.out.println(count);        if(count > 0){            System.out.println("添加成功！");        }else{            System.out.println("添加失败！");        }    } catch (ClassNotFoundException e) {        e.printStackTrace();    } catch (SQLException e) {        e.printStackTrace();    }finally {        //stmt.close();        //7. 释放资源        //避免空指针异常        if(stmt != null){            try {                stmt.close();            } catch (SQLException e) {                e.printStackTrace();            }        }        if(conn != null){            try {                conn.close();            } catch (SQLException e) {                e.printStackTrace();            }        }    }}

}