03jdbc的crud練習

//添加
package cn.itcast.jdbc;

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

/**

• account表 添加一條記錄 insert 語句

*/
public class JDBCDemo2 {

public static void main(String[] args) {
    Statement stmt = null;//放到try內部就是局部變量
    Connection conn = null;
    try {
        //1. 註冊驅動
        Class.forName("com.mysql.jdbc.Driver");
        //2. 定義sql
        String sql = "insert into account values(null,'王五',3000)";
        //3.獲取Connection對象
        conn = DriverManager.getConnection("jdbc:mysql:///db3", "root", "root");
        //4.獲取執行sql的對象 Statement
        stmt = conn.createStatement();
        //5.執行sql
        int count = stmt.executeUpdate(sql);//影響的行數
        //6.處理結果
        System.out.println(count);
        if(count > 0){
            System.out.println("添加成功！");
        }else{
            System.out.println("添加失敗！");
        }

    } catch (ClassNotFoundException e) {
        e.printStackTrace();
    } catch (SQLException e) {
        e.printStackTrace();
    }finally {
        //stmt.close();
        //7. 釋放資源
        //避免空指針異常
        if(stmt != null){
            try {
                stmt.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }

        if(conn != null){
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }


}

}