一个基于mysql的登陆验证程序_PHP

     /******************************************************
     file name: login.php3
     Login Check
     编码： PHP 4
     作者： Kevin Lee

     Database: MySQL。
     Host: localhost Database : mydb
     Table structure for table 'user'
--------------------------------------------------------
CREATE TABLE user (
   id smallint(6) NOT NULL auto_increment,
   user varchar(12) NOT NULL,
   passwd varchar(12) NOT NULL,
   name varchar(20),
   email varchar(30),
   level char(1),
   status char(1),
   UNIQUE id (id)
);
--------------------------------------------------------


    *******************************************************/
?>


  $db_id = mysql_pconnect("localhost", "root", "");
  $sql="select id, user, passwd from user where user='".$name."' and passwd='".$pwd."'";
  $result = mysql_db_query("mydb",$sql);
  $row = mysql_fetch_array($result);
  $id = $row[id] ;

  if ($id!="") {
    session_start();
    session_register("yn");
    $yn="yes"  ;
    echo "";
    echo "你已经成功登陆。。。"."

";
    echo "

"."窗口10秒钟后自动关闭"."";
    echo "";

  }
  else {
  echo "帐号或密码错误！！！";
  echo "

";
  echo "

";
  echo "back";
  echo "" ;
  }
?>