phpmysqli扩展库操作mysql的例子

1、mysqli扩展库操作mysql的dql

connect_error){
        die("连接失败".$mysqli->connect_error);
    }

    //2、操作数据库（发送sql）
    $sql="select *from user1";

    //3、处理结果
    $res =$mysqli->query($sql);
    //var_dump($res);
    //fetch_assoc \fetch_array \fetch_object
    while($row=$res->fetch_row()){

        var_dump($row);

/*        foreach($row as $val){
            echo '--'.$val;
        }
        echo '
';*/
    }
    //4、关闭资源
    $res->free();
    $mysqli->close();
?>

面向过程的例子：

';
    }

    //释放内存
    mysqli_free_result($res);
    mysqli_close($mysqli);
?>

2、mysqli扩展库对mysql的dml操作

connect_error){
        die("连接失败".$mysql->connect_error);
    }

    //增加一条记录
    //$sql="insert into user1 (name,password,email,age) values ('lucy',md5('lucy'),'lucy@163.com',17)";
    //删除一条记录
    //$sql="delete from user1 where id =80";
    //更新一条记录
    $sql="update user1 set age=20 where id=7";

    $res=$mysqli->query($sql);
    if(!$res){
        echo "操作失败".$mysqli->error;
    }else{
        if($mysqli->affected_rows>0){
            echo "成功";
        }else{
            echo "没有行受影响";    
        }
    }

    //关闭资源
    $mysqli->close();
?>

3、进行封装

mysqli=new MySQLi(self::$host,self::$user,self::$pwd,self::$db);
            if($this->mysqli->connect_error){
                die("连接失败".$this->mysqli->connect_error);
            }
            //设置字符集
            $this->mysqli->query("set names utf8");
        }

        //dql operate
        function execute_dql($sql){

            $res =$this->mysqli->query($sql) or die($this->mysqli->error);
            return $res;        
        }

        //dml operate
        function execute_dml($sql){

            $res =$this->mysqli->query($sql) or die($this->mysqli->error);
            
            if(!$res){
                return 0;//失败
            }else{
                if($this->mysqli->affected_rows>0){
                    return 1;//成功
                }else{
                    return 2;//没有行到影响
                }
            }
        }
    }
?>