How to refresh a database query using jQuery - php

Question

I'm working on a real basic chat that is mostly php powered. I'd like to use jQuery to check for new messages and update the #cbox div every few seconds. So far I have tried accomplishing that using the code below. For a frame of reference, this is my first time including jQuery into any of my scripts, so the problem is likely a very simple error that I am overlooking in my newbishness.
The problem I'm running into is the #cbox div displays blank, it doesn't seem to be calling to chat_post.php at all. I will post that code as well, in case the problem is with that and not with my jQuery. To fix, I tried also including <div id='cbox'> in chat_post.php, but that yielded no results. At this point, I'm pretty much grasping at straws.
<div id='sb_content'>
<center><div id='chat'>
<div id='ribbon' style='position: relative; margin-top:-50px; margin-left:-32px;'><center><span class='ribbon'>chat box</span></center></div>
<div style='margin-top: -20px;'><center><span style='text-shadow: 0 0 0.2em #000;' class='admin'>admin</span> || <span style='text-shadow: 0 0 0.2em #000;' class='mod'>mod</span></center></div>
<div id="cbox">
<script>
$(document).ready(function() {
setInterval(function(){getUpdates()}, 2000);
});
function getUpdates() {
$("#cbox").load("chat_post.php");
}
</script>
</div>
<form name="message" method='post' action="chat_post.php" id="cbox_input">
<input name="usermsg"id='usermsg' type="text" size="63" maxlength="255" />
</form>
</div></center>
</div>
chat_post.php
<div id='cbox' align='left'>
<?php
$username = $_SESSION['login'];
$ug = $_SESSION['user_group'];
// Display messages
$sql = <<<SQL
SELECT *
FROM `chat_entries`
ORDER BY `ts` DESC
LIMIT 0,50
SQL;
$result = $db->query($sql);
$count = $result->num_rows;
if ($count != 0){
while ($row = mysqli_fetch_array($result)) {
$c_name = $row['author'];
$c_text = $row['text'];
$c_ts = $row['ts'];
$c_id = $row['id'];
$sqlm = <<<SQL
SELECT *
FROM `users`
WHERE username = '$c_name'
SQL;
$resultm = $db->query($sqlm);
$countm = $resultm->num_rows;
if ($count != 0){
while ($rowm = mysqli_fetch_array($resultm)) {
$c_level = $rowm['user_group'];
}
}
if ($c_level == 'mod') {
echo "
<a href='/user/" . $c_name . "' class='mod'>" . $c_name . "</a>
";
}
if ($c_level == 'admin') {
echo "
<a href='/user/" . $c_name . "' class='admin'>" . $c_name . "</a>
";
}
if ($c_level == 'member') {
echo "
<a href='/user/" . $c_name . "' class='member'>" . $c_name . "</a>
";
}
if ($c_level == 'guest') {
echo "
<i>" . $c_name . "</i>
";
}
echo "
: " . $c_text . "<div id='cbox_div'>";
echo "<span style='float:left;'><i>" . $c_ts . "</i></span>";
echo "<span style='float:right;'>";
if ($ug == 'mod' || $ug == 'admin'){
echo " <a href='#'>Delete</a> || <a href='#'>Block</a> ||";
}
if ($_SESSION['login']) {
echo "Report</span></div>
";
}
}
}
?>

Answer 1

After removing the extra id on chat_post.php, my code worked just fine. Funny how something so simple can really mess things up. (: Thank you everyone for your help!