get_results("SELECT * FROM $wpdb->categories WHERE category_count > 0 ORDER BY cat_name DESC"); // query database for categories with at least one post; foreach($categories as $category) : // start loop to display category list ?>

cat_name; ?> cat_ID; endif; if( (is_category() || is_single()) && ($category->cat_ID === $cat) ) : // current category query is same as category presently in the loop ?>

have_posts()) : $catq->the_post(); // start posts in category loop ?>