Help with query which may contain empty variables

SonicReducer

I am creating a search form for users to find restaurants. The parameters are all passed via url from the page with the form to the results page. There are 4 parameters and the user can select any combination of them to do the search. 3 are drop downs and one is a text box (restname).

I tried the code below but I'm not getting any results to show. Any ideas where I'm going wrong?

 <?php require_once('Connections/xxxx.php'); ?>
<?php
mysql_select_db($database_xxxx, $xxxx);
$query = array();

if($_GET['county'] != "none"){
     // Filter results by county
     $query[] = "county='".addslashes($_GET['county'])."'";
}

if($_GET['price'] != "none"){
     // Filter results by cost
     $query[] = "price='".addslashes($_GET['price'])."'";
}

if($_GET['restname'] != "none"){
     // Filter results by name
     $query[] = "restname='".addslashes($_GET['restname'])."'";
}

// This line puts the string " AND " between each element of the array so it becomes something like "county='xxx' AND cost='xxx'"
$where = implode(" AND ",$query);

if(!empty($where)){
     // Run the query and get results
     $results = mysql_query("SELECT * FROM StatewideDining WHERE {$where}") or die(mysql_error()); 

 // Your result resource is $results
}else{
     echo "The user didn't fill out any fields of the form, generate an error";
}
?>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>Untitled Document</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
</head>
<body><br>
<?php do { ;?>
<?php echo $row_results['county']; echo $row_results['restname'];?>
<?php } while($row_results=($result)); ?>


</body>

</html>
<?php
mysql_free_result($results);
?>

Sxooter

1: Don't use add_slashes, it's not hack proof. Use mysql_escape_whatever functions (lookemup, each db has its own) they are safe.
2: Is it acceptable to NOT have any where clause on this application? For some apps that's fine, for others, with say 100,000,000 records, it's just not acceptable to NOT have a where clause. This will determine how you write your application code.
3: Assuming that no where clause is ok, then you can't just assume to have one in your query.

Here's some code, not guaranteed to work exactly, but you'll get the idea:

<?php
if($_GET['county'] != "none"){
     // Filter results by county
     $query[] = "county='".mysql_real_escape($_GET['county'])."'"; # Not sure of the function name.  it's something like that

if($_GET['price'] != "none"){
     // Filter results by cost
     $query[] = "price='".mysql_real_escape($_GET['price'])."'";
}

if($_GET['restname'] != "none"){
     // Filter results by name
     $query[] = "restname='".mysql_real_escape$_GET['restname'])."'";
}

$q = "select * from table ";
if (count($query)>0){
    $q.="where ";
    $q.=implode(" AND ",$query);
}
?>