need help with why tag cloud doesn't work

[webguync]

Hey there, I am trying out some tag cloud code, but something is amiss, as am getting no tags displaying. Using PHP/MYSQL and JQuery.

<?php

//connection information
  $host = "localhost";
  $user = "username";
  $password = "pw";
  $database = "DBName";

//make connection
  $server = mysql_connect($host, $user, $password);
  $connection = mysql_select_db($database, $server);

//query the database
  $query = mysql_query("SELECT * FROM tags");


//start json object
$json = "({ tags:["; 

//loop through and return results
  for ($x = 0; $x < mysql_num_rows($query); $x++) {
    $row = mysql_fetch_assoc($query);

	//continue json object
    $json .= "{tag:'" . $row["tag"] . "',freq:'" . $row["frequency"] . "'}";

	//add comma if not last row, closing brackets if is
	if ($x < mysql_num_rows($query) -1)
		$json .= ",";
	else
		$json .= "]})";
  }

//return JSON with GET for JSONP callback
$response = $_GET["callback"] . $json;
echo $response;

//close connection
mysql_close($server);

?>

and the JS

 

<script type="text/javascript">
		$(function() {

			//get tag feed
			$.getJSON("/tagcloud.php?callback=?", function(data) {

				//create list for tag links
				$("<ul>").attr("id", "tagList").appendTo("#tagCloud");

				//create tags
				$.each(data.tags, function(i, val) {

					//create item
					var li = $("<li>");

					//create link
					$("<a>").text(val.tag).attr({title:"See all pages tagged with " + val.tag, href:"http://localhost/tags/" + val.tag + ".html"}).appendTo(li);

					//set tag size
					li.children().css("fontSize", (val.freq / 10 < 1) ? val.freq / 10 + 1 + "em": (val.freq / 10 > 2) ? "2em" : val.freq / 10 + "em");

					//add to list
					li.appendTo("#tagList");

				});
			});
		});
	</script>

 

when i turn on error reporting I get a lot of undefined index notices for tag and frequency so not sure if that is causing the problem or not.

[GrooN]

Now before reading your code throughout, I have to ask, is there any special reason why you don't use the function json_encode()? ^^ - or did you know if its existence at all?

[webguync]

I didn't know of it's existence. Please explain!

[GrooN]

Well it is not that complicated, it encodes your object into json format ^^

 

You can read more about it here: http://php.net/manual/en/function.json-encode.php

 

And when you use json_encode, you should also know json_decode, which does the opposite