oracle
8.1.6
select r.recommendation_id, r.the_category_name, r.the_subcategory_name, r.the_subsubcategory_name, p.product_name, c.user_class_name
from ec_recommendations_cats_view r, ec_products p, ec_user_classes c
where r.product_id=p.product_id and r.user_class_id = c.user_class_id(+) and r.active_p='t'
order by DECODE(the_category_name,null,0,1), upper(the_category_name),
upper(the_subcategory_name),
upper(the_subsubcategory_name)