How get in one query which forum(s)are moderated by which moderator(s)

<?php
define('PUN_ROOT', './');
require PUN_ROOT.'include/common.php';

// Get the array the right way!
$mod_users = array();
$result = $db->query("SELECT id, forum_name, moderators FROM ".$db->prefix."forums WHERE moderators IS NOT NULL")  or error('Unable to fetch forum info', __FILE__, __LINE__, $db->error());;
while ($cur_forum = $db->fetch_assoc($result))
{
    $cur_forum['moderators'] = unserialize($cur_forum['moderators']);
    
    foreach ($cur_forum['moderators'] as $mod_name => $mod_id)
    {
        $mod_users[$mod_name][$cur_forum['id']] = $cur_forum['forum_name'];
    }
}

require PUN_ROOT.'header.php';
?>
<div class="blockform">
    <h2><span>Moderator List</span></h2>
    <div class="box">
    <form method="post" action="thisisfake.php">
<?php
foreach ($mod_users as $mod_name => $forums)
{
?>
        <div class="inform">
            <fieldset>
                <legend><?php echo $mod_name ?></legend>
                <div class="infldset">
<?php
foreach ($forums as $forum_id => $forum_name)
{
?>
                    <label><a href="viewforum.php?id=<?php echo $forum_id ?>"><?php echo $forum_name ?></a></label>
<?php
}
?>
                </div>
            </fieldset>
        </div>
<?php
}
?>
    </form>
    </div>
</div>
<?php
require PUN_ROOT.'footer.php';