Check User Name: Isn't happening

Question

I have a registration page in JavaScript that is working fine except for the fact that I need it to check username against the database to insure that usernames do not get duplicated in the database. Because it does not check username I come to realize that user’s information is getting mixed up if the username are the same.  I am sure I am not doing this correctly because I have not used JavaScript before…. So I than created an Insert Record on the registration:
Submit Values From: Form 1
Connection: Rescue
Insert Table: user_registration
Columns: ‘ID’Gets Value From “FORM.username as Integer’
Submit as: Integer
After insert, go to: myprofile.php
After creating the Insert Record I created the Check New Username:
Username Field: username
If already exist, go to: register.php
So I tested to see if what I added worked and it does not.  What does happen- is when I create a new record in which the user has the same username that is all ready in the database…it allows me to create a duplicate username in the database and then send me to the following blank screen with the URL: http://www.rescuealerts.com/forms/user_registration/user_registration.php. Instead of sending me back to registration page to try again. I also realize I need to program in a message stating that username is unavailable try again but I hadn’t gotten to that point because I am first trying to get the Check New Username to work.  Please find below the code for the Insert Record, the Check New Username and the registration input form.
Insert Record and Check New Username Code:
<?php require_once('Connections/rescue.php'); ?>
<?php
if (!function_exists("GetSQLValueString")) {
function GetSQLValueString($theValue, $theType, $theDefinedValue = "", $theNotDefinedValue = "")
  if (PHP_VERSION < 6) {
    $theValue = get_magic_quotes_gpc() ? stripslashes($theValue) : $theValue;
  $theValue = function_exists("mysql_real_escape_string") ? mysql_real_escape_string($theValue) : mysql_escape_string($theValue);
  switch ($theType) {
    case "text":
      $theValue = ($theValue != "") ? "'" . $theValue . "'" : "NULL";
      break;   
    case "long":
    case "int":
      $theValue = ($theValue != "") ? intval($theValue) : "NULL";
      break;
    case "double":
      $theValue = ($theValue != "") ? doubleval($theValue) : "NULL";
      break;
    case "date":
      $theValue = ($theValue != "") ? "'" . $theValue . "'" : "NULL";
      break;
    case "defined":
      $theValue = ($theValue != "") ? $theDefinedValue : $theNotDefinedValue;
      break;
  return $theValue;
// *** Redirect if username exists
$MM_flag="MM_insert";
if (isset($_POST[$MM_flag])) {
  $MM_dupKeyRedirect="register.php";
  $loginUsername = $_POST['username'];
  $LoginRS__query = sprintf("SELECT ID FROM user_registration WHERE ID=%s", GetSQLValueString($loginUsername, "int"));
  mysql_select_db($database_rescue, $rescue);
  $LoginRS=mysql_query($LoginRS__query, $rescue) or die(mysql_error());
  $loginFoundUser = mysql_num_rows($LoginRS);
  //if there is a row in the database, the username was found - can not add the requested username
  if($loginFoundUser){
    $MM_qsChar = "?";
    //append the username to the redirect page
    if (substr_count($MM_dupKeyRedirect,"?") >=1) $MM_qsChar = "&";
    $MM_dupKeyRedirect = $MM_dupKeyRedirect . $MM_qsChar ."requsername=".$loginUsername;
    header ("Location: $MM_dupKeyRedirect");
    exit;
$editFormAction = $_SERVER['PHP_SELF'];
if (isset($_SERVER['QUERY_STRING'])) {
  $editFormAction .= "?" . htmlentities($_SERVER['QUERY_STRING']);
if ((isset($_POST["MM_insert"])) && ($_POST["MM_insert"] == "form1")) {
  $insertSQL = sprintf("INSERT INTO user_registration (ID) VALUES (%s)",
                       GetSQLValueString($_POST['username'], "text"));
  mysql_select_db($database_rescue, $rescue);
  $Result1 = mysql_query($insertSQL, $rescue) or die(mysql_error());
  $insertGoTo = "myprofile.php";
  if (isset($_SERVER['QUERY_STRING'])) {
    $insertGoTo .= (strpos($insertGoTo, '?')) ? "&" : "?";
    $insertGoTo .= $_SERVER['QUERY_STRING'];
  header(sprintf("Location: %s", $insertGoTo));
?>
Registration Code:
<script src='http://www.rescuealerts.com/forms/user_registration/scripts/gen_validatorv5.js' type='text/javascript'></script>
<script src='http://www.rescuealerts.com/forms/user_registration/scripts/sfm_captcha_validator.js' type='text/javascript'></script>
<script src='http://www.rescuealerts.com/forms/user_registration/scripts/sfm-png-fix.js' type='text/javascript'></script>
<link rel='stylesheet' type='text/css' href='http://www.rescuealerts.com/forms/user_registration/style/user_registration.css'/>
<form id='user_registration' method='post' action='http://www.rescuealerts.com/forms/user_registration/user_registration.php' accept-charset='UTF-8'>
   <div id='user_registration_errorloc' class='error_strings' style='width:500px;text-align:left'></div>
  <div id='user_registration_outer_div' style='width:500px;height:1120px'>
      <div style='position:relative; font-weight: normal;' id='user_registration_inner_div'>
         <input type='hidden' name='sfm_form_submitted' value='yes'/>
         <div id='heading_container'>
            <div id='heading'>Please Enter Your Information Here:</div>
         </div>
         <div id='Image2_container'>
            <img class='sfm_image_in_form' src='http://www.rescuealerts.com/forms/user_registration/images/rescue_logo_3 copy.jpg' width='128' height='24' alt='Rescue Alerts Logo'/>
         </div>
         <div id='register_name_container'>
            <input type='text' name='register_name' id='register_name' size='20' class='sfm_textbox'/>
         </div>
         <div id='label39_container'>
            <label id='label39' for='register_name' class='sfm_form_label'>Name:</label>
         </div>
         <div id='register_semail_container'>
            <input type='text' name='register_semail' id='register_semail' size='20' class='sfm_textbox'/>
         </div>
         <div id='register_pemail_container'>
            <input type='text' name='register_pemail' id='register_pemail' size='20' class='sfm_textbox'/>
         </div>
         <div id='label2_container'>
            <label id='label2' for='register_pemail' class='sfm_form_label'>Primary Email:</label>
         </div>
         <div id='label3_container'>
            <label id='label3' for='register_semail' class='sfm_form_label'>Secondary Email:</label>
         </div>
         <div id='register_cellphone_container'>
            <input type='text' name='register_cellphone' id='register_cellphone' size='20' class='sfm_textbox'/>
         </div>
         <div id='register_phone_container'>
            <input type='text' name='register_phone' id='register_phone' size='20' class='sfm_textbox'/>
         </div>
         <div id='label4_container'>
            <label id='label4' for='register_phone' class='sfm_form_label'>Home Phone:</label>
         </div>
         <div id='label5_container'>
            <label id='label5' for='register_cellphone' class='sfm_form_label'>Cell Phone:</label>
         </div>
         <div id='register_pass_container'>
            <input type='password' name='register_pass' id='register_pass' size='20' class='sfm_textbox'/>
         </div>
         <div id='register_login_container'>
            <input type='text' name='register_login' id='register_login' size='20' class='sfm_textbox'/>
         </div>
         <div id='label6_container'>
            <label id='label6' for='register_pass' class='sfm_form_label'>User Password:</label>
         </div>
         <div id='label38_container'>
            <label id='label38' for='register_login' class='sfm_form_label'>User Login:</label>
         </div>
         <div id='heading1_container'>
            <div id='heading1'>Enter Emergency Contact  Information Here:</div>
         </div>
         <div id='label14_container'>
            <div id='label14'>Contact 1:</div>
         </div>
         <div id='con1_cell_container'>
            <input type='text' name='con1_cell' id='con1_cell' size='20' class='sfm_textbox'/>
         </div>
         <div id='con1_name_container'>
            <input type='text' name='con1_name' id='con1_name' size='20' class='sfm_textbox'/>
         </div>
         <div id='label11_container'>
            <label id='label11' for='con1_cell' class='sfm_form_label'>Cell Phone:</label>
         </div>
         <div id='label40_container'>
           <label id='label40' for='con1_name' class='sfm_form_label'>Name:</label>
         </div>
         <div id='con1_land_container'>
            <input type='text' name='con1_land' id='con1_land' size='20' class='sfm_textbox'/>
         </div>
         <div id='label10_container'>
            <label id='label10' for='con1_land' class='sfm_form_label'>Land Line:</label>
         </div>
         <div id='con1_email_container'>
            <input type='text' name='con1_email' id='con1_email' size='20' class='sfm_textbox'/>
         </div>
         <div id='label12_container'>
            <label id='label12' for='con1_email' class='sfm_form_label'>Email:</label>
         </div>
         <div id='label15_container'>

Answer 1

hjohnson2011 wrote:
I have a registration page in JavaScript that is working fine except for the fact that I need it to check username against the database to insure that usernames do not get duplicated in the database. Because it does not check username I come to realize that user’s information is getting mixed up if the username are the same.  I am sure I am not doing this correctly because I have not used JavaScript before….
When asking for help, you stand a much better chance of getting the answers you need if you create a simple test page to illustrate the problem, rather than posting hundreds of lines of code. A test page helps isolate the problem without being distracted by everything else in your complex form.
What's not clear from your description is what the JavaScript is intended to do. Taking a quick look at the code you have posted here, the Insert Record server behavior handles only the username. Yet your form has dozens of fields. Also, the form's action attribute points to user_registration.php. Is this the same page or a different script? If it's a different script, that's what's inserting the values into the database. The Check User Name server behavior is never called. Or is an external JavaScript file taking the values after validation and using an Ajax call to insert them in the database? Again, this would bypass the Check User Name server behavior.
Having said that, the Check User Name server behavior is, to my mind, worse than useless, because it redirects the user to another page, thereby losing all the user input. The simple solution is to add a UNIQUE index to the username column in the database. This prevents a duplicate entry from being inserted. However, you need to customize the Insert Record server behavior to intercept the MySQL error like this:
  // remove the or die() clause
  $Result1 = mysql_query($insertSQL, $rescue);
  // if the username is already in use
  if (!$Result1 && mysql_errno() == 1062) {
      $error = $_POST['username'] . ' is already in use. Choose another.';
  } elseif (mysql_error()) {
      $error = 'Sorry, there is a problem with the database. Try later.';
  } else {
      $insertGoTo = "myprofile.php";
      if (isset($_SERVER['QUERY_STRING'])) {
        $insertGoTo .= (strpos($insertGoTo, '?')) ? "&" : "?";
        $insertGoTo .= $_SERVER['QUERY_STRING'];
      header(sprintf("Location: %s", $insertGoTo));
  }  // close extra conditional statement
You can then redisplay the page if the username is already taken, and use the $_POST array to preserve the user's input in the form.