php数据库有关问题，

<?php <br />
$user123 = $_POST['user']; <br />
$db = new mysqli($sqln,$sqlu,$sqlp,$sqld) or die("Error in the consult.." . mysqli_error($db)); <br />
$query = "SELECT 'user_email' FROM 'user' WHERE 'user_email' = '$user123'"; <br />
// mysql_select_db($sqld); <br />
mysqli_select_db($db, $sqld); <br />
$result = $db->query($query) or die("Error in the consult.." . mysqli_error($db)); <br />
if ($result == 1){ <br />
echo "<p> 登陆成功 </p>"; <br />
} <br />
elseif ($result == 0){ <br />
echo "<p> 没有找到 </p>"; <br />
} <br />
<br />
echo $_POST["user"]; <br />
$dba = $db->affected_rows; <br />
echo $dba; <br />
mysqli_close($db); <br />
?>