PHP + MySQL categories not displayed as should be

Question

I have no clue as to why but sub-categories "forums" of my script aren't being groped to there respective category. Instead the sub-category forces the script to repeat the Category code.

As show in the image below there is a category Test, in that category theres Test and Bugs. However Bugs is slip into 2nd table which it should not be as both Test categories are one, but instead its made to look like there are two categories in the database called Test. What is wrong in my code that Bugs is being pushed into copy-Category "Test" instead of it being right under Test - Just a simple test forum?

And here is the code.

<?php

include 'connect.php';
include 'header.php';

$sql = "SELECT
            categories.cat_id,
            categories.cat_name,
            forums.forum_id,
            forums.forum_cat,
            forums.forum_name,
            forums.forum_desc,
            COUNT(forums.forum_id) AS forums
        FROM
            categories
        LEFT JOIN
            forums
        ON
            forums.forum_cat = categories.cat_id
        GROUP BY
            forums.forum_name, forums.forum_desc, forums.forum_id
        ORDER BY
            categories.cat_id ASC
        ";

$result = mysql_query($sql);

if(!$result)
{
    echo 'The categories could not be displayed, please try again later.';
}
else
{
    if(mysql_num_rows($result) == 0)
    {
        echo 'No categories defined yet.';
    }
    else
    {
        //prepare the table         
        while($row = mysql_fetch_assoc($result))
        {   

        echo '<table border="1">
              <tr>
                <th>' . $row['cat_name'] . '</th><th></th>
                </tr>';     
            echo '<tr>';

                echo '<td class="leftpart">';
                    echo '<h3><a href="viewforum.php?id=' . $row['forum_id'] . '">' . $row['forum_name'] . '</a></h3>' . $row['forum_desc'];
                echo '</td>';
                echo '<td class="rightpart">';

                //fetch last topic for each cat
                    $topicsql = "SELECT
                                    topic_id,
                                    topic_subject,
                                    topic_date,
                                    topic_cat
                                FROM
                                    topics
                                WHERE
                                    topic_cat = " . $row['forum_id'] . "
                                ORDER BY
                                    topic_date
                                DESC
                                LIMIT
                                    1";

                    $topicsresult = mysql_query($topicsql);

                    if(!$topicsresult)
                    {
                        echo 'Last topic could not be displayed.';
                    }
                    else
                    {
                        if(mysql_num_rows($topicsresult) == 0)
                        {
                            echo 'no topics';
                        }
                        else
                        {
                            while($topicrow = mysql_fetch_array($topicsresult))
                            echo '<a href="viewtopic.php?id=' . $topicrow['topic_id'] . '">' . $topicrow['topic_subject'] . '</a> at ' . date('d-m-Y', strtotime($topicrow['topic_date']));
                        }
                    }
                echo '</td>';
            echo '</tr>';
            echo '</br>';
        }
    }
}

include 'footer.php';
?>

Table structure

Categories

cat_id     | int(8) | primary | auto incr
cat_name   | var(255)

|2|Damm
|3|Hmm
|1|Test

Forums

forum_id   | int(8) | primary | auto_incr
forum_cat  | int(8) <-- forum cat "category" is just ID of category it belongs to
forum_name | var(255)
forum_desc | var(255)

|1|1|Test|Just a simple forum test
|2|3|Lol
|3|1|Bugs|Bugs and related go here

Topics

topic_id   | int(8) | primary | auto_incr
topic_subject | var(255)
topic_date    | datetime
topic_cat     | int(8) 
topic_by      | int(8)

|1|Test|2012-07-31 23:12:47|1|1

I personally tried different things but still can't figure out why this is happening.

Answer 1

You will have results along the lines of

cat_id 1, forum_id 1
cat_id 1, forum_id 2
cat_id 1, forum_id 3
cat_id 2, forum_id 4

But you output everything in one loop, so what you need to do is remember the last header shown, and only show a new header if you're in a new category.

The below is an example, not perfect, but will give you a start

// Start the table here - outside the loop
echo '<table border="1">  

// Here's how you track if you need the header
$lastCatID = -1

// Now loop
while($row = mysql_fetch_assoc($result))  
{     
    // Only show cat header on condition
    if ($lastCatID <> $row['cat_id']) {
        echo '
          <tr>  
            <th>' . $row['cat_name'] . '</th><th></th>  
            </tr>';

        // Note that you've shows this header so you don't show it again.
        $lastCatID = $row['cat_id'];
    }

    // Now output the rest       
    echo '<tr>';  
    echo '<td class="leftpart">';  
        etc....
    echo '</tr>';  
}

// Now close the table now you're all done looping.
echo '</table>';

Hope that helps. You should be able to expand from there to fit your styles.