query optimering

Hejsa,

Kan denne query optimeres?

// Get server info
$server_query = mysql_query("SELECT id,domain FROM servers WHERE enable='1' AND free_diskspace > buffer*1024*1024 AND free_tmp > buffer*1024*1024 ORDER BY rand() LIMIT 1") or die (mysql_error());
$server_fetch = mysql_fetch_array($server_query);
$server_num = mysql_num_rows($server_query);
$server_id = $server_fetch[id];
$server_domain = $server_fetch[domain];

// Check if free diskspace is blow the buffer size
if($server_num == 0) {

    // Post error message
    $status = 25;
    include "/home/domain/include/status_error.php";
    exit();
}