为什么只有数字工作正常时Alpha数字抛出错误？ [重复]

When I use "55555555555555555" it returns the values, when I use "A5555555555555555" I get Warning: mysql_fetch_array() expects parameter 1 to be resource, boolean given in C:\xampp\htdocs\bidTobuy2.php on line 35 []

<?php
$VIN = "A5555555555555555";

$result = mysql_query("SELECT VIN, Bid, BoughtFrom, Mileage from tblevaluated WHERE VIN     = $VIN");



  $json_response = array();
  ////line 35: 
  while ($row = mysql_fetch_array($result, MYSQL_ASSOC)) { 
  $row_array['BoughtFrom'] = $row['BoughtFrom'];
  $row_array['Bid'] = $row['Bid'];   
  $row_array['miles'] = $row['Mileage']; 


    array_push($json_response,$row_array);

}

echo json_encode($json_response);

?>

</div>

strings vs numbers, man. need to quote them.

$result = mysql_query("SELECT VIN, Bid, BoughtFrom, Mileage from tblevaluated WHERE VIN = '$VIN'");

The quotes at the end need to be moved in

$result = mysql_query("SELECT VIN, Bid, BoughtFrom, Mileage from tblevaluated WHERE VIN     = $VIN");

Should be

$sql = "SELECT VIN, Bid, BoughtFrom, Mileage from tblevaluated WHERE VIN  = '" . $VIN . "'";
$result = mysql_query($sql);

Edit: Yeah, as they said, strings definitely need to be wrapped. Updated.