Something

    if(preg_match('/[A-Za-z]+/',$hostname)){
    $hostname_sql = "UPDATE `ip_information` SET dns_name = '$hostname' WHERE ip = '$ip2edit'";
    mysql_query($hostname_sql,$connection) or die(mysql_error());
    $verify .= "You changed the hostname to $hostname.<br>\n";
    }

      if(preg_match('/[A-Za-z]+/',$details)){
      $details_sql = "UPDATE `ip_information` SET details = '$details' WHERE ip = '$ip2edit'";
      mysql_query($details_sql,$connection) or die(mysql_error());
      $verify .= "You changed the details to $details.<br>\n";
      }

        if(preg_match('/[0-9]+/',$date)){
        $date_sql = "UPDATE `ip_information` SET last_mod = '$date' WHERE ip = '$ip2edit'";
        mysql_query($date_sql,$connection) or die(mysql_error());
        $verify .= "You changed the date to $date.<br>\n";
        }