--q23a.sql--

 with frequent_ss_items as
 (select substr(i_item_desc,1,30) itemdesc,i_item_sk item_sk,d_date solddate,count(*) cnt
  from store_sales, date_dim, item
  where ss_sold_date_sk = d_date_sk
    and ss_item_sk = i_item_sk
    and d_year in (2000, 2000+1, 2000+2,2000+3)
  group by substr(i_item_desc,1,30),i_item_sk,d_date
  having count(*) >4),
 max_store_sales as
 (select max(csales) tpcds_cmax
  from (select c_customer_sk,sum(ss_quantity*ss_sales_price) csales
        from store_sales, customer, date_dim
        where ss_customer_sk = c_customer_sk
         and ss_sold_date_sk = d_date_sk
         and d_year in (2000, 2000+1, 2000+2,2000+3)
        group by c_customer_sk) x),
 best_ss_customer as
 (select c_customer_sk,sum(ss_quantity*ss_sales_price) ssales
  from store_sales, customer
  where ss_customer_sk = c_customer_sk
  group by c_customer_sk
  having sum(ss_quantity*ss_sales_price) > (95/100.0) *
    (select * from max_store_sales))
 select sum(sales)
 from (select cs_quantity*cs_list_price sales
       from catalog_sales, date_dim
       where d_year = 2000
         and d_moy = 2
         and cs_sold_date_sk = d_date_sk
         and cs_item_sk in (select item_sk from frequent_ss_items)
         and cs_bill_customer_sk in (select c_customer_sk from best_ss_customer)
      union all
      (select ws_quantity*ws_list_price sales
       from web_sales, date_dim
       where d_year = 2000
         and d_moy = 2
         and ws_sold_date_sk = d_date_sk
         and ws_item_sk in (select item_sk from frequent_ss_items)
         and ws_bill_customer_sk in (select c_customer_sk from best_ss_customer))) x
 limit 100