| select product_class.product_family as c0 from product as product, product_class as product_class, sales_fact_1997 as sales_fact_1997, time_by_day as time_by_day where product.product_class_id = product_class.product_class_id and sales_fact_1997.product_id = product.product_id and sales_fact_1997.time_id = time_by_day.time_id and time_by_day.the_year = 1997 group by product_class.product_family having NOT((sum(sales_fact_1997.store_cost) is null)) order by product_class.product_family ASC NULLS LAST; |