Typecho 获取网站标签总数目

/**
* 获取标签数目
* 
* 语法: <?php echo tagsNum(); ?>
* 
* @access protected
* @return integer
*/
function tagsNum($display = true)
{
        $db = Typecho_Db::get();
        $total_tags = $db->fetchObject($db->select(array('COUNT(mid)' => 'num'))
              ->from('table.metas')
              ->where('table.metas.type = ?', 'tag'))->num;
        if($display) {
            echo $total_tags;
        } else {
            return $total_tags;
        }
}