Sayfaya güvenlik için şu şekilde bi giriş koydum çalışıyor fakat sürekli hata veriyor

error_log
[18-Dec-2010 18:32:14] PHP Warning:  mysql_fetch_assoc(): supplied argument is not a valid MySQL result resource in /home/xxxxx/public_html/rehber/index.php on line 145
index.php içeriği

<?php
$ourLogin = "altan";
$ourPassword = "101010";

session_start();

if ($_SESSION['login']!=$ourLogin && $_SESSION['password']!=$ourPassword) {


if ($_POST['login']==$ourLogin && $_POST['password']==$ourPassword) {


$_SESSION['login'] = $_POST['login'];
$_SESSION['password'] = $_POST['password'];
header("Location: index.php");


}
else {


echo "
<form action=index.php method=post>


Login:<br>
<input type=text name=login value=''><br>

Password:<br>
<input type=password name=password value=''><br>

<input type=submit value=Giriş >


</form>
";

exit;

}

}
?>	<?php include("ayar.php");?>
<?php
$ara = $_POST['veri'];
$secim = $_POST['select'];

if($secim == "no") { 
    $anahtar = "OgrNo"; 
}elseif($secim == "sinif"){
    $anahtar = "SinifNo";
}elseif($secim == "adi"){
    $anahtar = "Ad";
}elseif($secim == "soyadi"){
    $anahtar = "Soyad";
}


$sorgu = mysql_query("select * from deneme2 WHERE ".$anahtar." LIKE '%".$ara."%'");

?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-9" />
<title>Telefon Rehberi</title>
<style type="text/css">
<!--
.style1 {font-weight: bold}
.style2 {font-weight: bold}
body {
	background-image: url(arka2.png);
}
a:link {
	color: #FFFFFF;
	text-decoration: none;
}
a:visited {
	text-decoration: none;
	color: #FFFFFF;
}
a:hover {
	text-decoration: none;
	color: #FFFFFF;
}
a:active {
	text-decoration: none;
	color: #FFFFFF;
}
-->
</style>
</head>

<body><table align="center">
<form id="form1" name="form1" method="post" action="#">
  <table width="1278" border="0" align="center">
    <tr align="center">
      <th width="346" scope="col"><div align="center">

        <div align="right">
          <input type="text" name="veri" />
          <select name="select">
            <option value="adi" selected="selected">Adı</option>
            <option value="soyadi">Soyadı</option>
            <option value="sinif">Sınıf</option>
            <option value="no">No</option>
          </select>
          <input type="submit" name="Submit" value="Ara" />
          </div>
    </form><?php
$get = $_GET["id"];
?><a href="javascript:print('sayfa.php?id<?= $get; ?>' )">Yazdır</a>
      </th>
      <th width="922" scope="col"></th>
    </tr>
  </table>



<table width="1070" border="1" align="center">
  <tr>
    <th width="44" bgcolor="#CCCCCC" scope="col"> No </th>
    <th width="47" bgcolor="#CCCCCC" scope="col">Sınıf  </th>
    <th width="143" bgcolor="#CCCCCC" scope="col"> Adı </th>
    <th width="95" bgcolor="#CCCCCC" scope="col">Soyadı</th>
    <th width="120" bgcolor="#CCCCCC" scope="col">Telefon No </th>
    <th width="120" bgcolor="#CCCCCC" scope="col">Mobil No </th>
    <th width="119" bgcolor="#CCCCCC" scope="col">Anne Mobil </th>
    <th width="91" bgcolor="#CCCCCC" scope="col">Anne Adı </th>
    <th width="120" bgcolor="#CCCCCC" scope="col">Baba Mobil </th>
    <th width="107" bgcolor="#CCCCCC" scope="col">Baba Adı </th>
  </tr>
<?php 

while($veri = mysql_fetch_assoc($sorgu)){?>
  <tr>
    <th height="2" bgcolor="#FFFFFF" scope="row"><?php echo $veri[OgrNo]; ?></th>
    <td bgcolor="#FFFFFF"><?php echo $veri[SinifNo]; ?></td>
    <td bgcolor="#FFFFFF"><?php echo $veri[Ad]; ?></td>
    <td bgcolor="#FFFFFF"><?php echo $veri[Soyad]; ?></td>
    <td bgcolor="#FFFFFF"><?php echo $veri[Tel]; ?></td>
    <td bgcolor="#FFFFFF"><?php echo $veri[Mobil]; ?></td>
    <td bgcolor="#FFFFFF"><?php echo $veri[AnneMobil]; ?></td>
    <td bgcolor="#FFFFFF"><?php echo $veri[AnneAd]; ?></td>
    <td bgcolor="#FFFFFF"><?php echo $veri[BabaMobil]; ?></td>
    <td bgcolor="#FFFFFF"><?php echo $veri[BabaAd]; ?></td>
  </tr>
  <?php } ?>
</table>
</body>

</html>

hata olduğunu bildirilen satır
while($veri = mysql_fetch_assoc($sorgu)){?>