WITH ws AS
  (SELECT d_year AS ws_sold_year,
          ws_item_sk,
          ws_bill_customer_sk ws_customer_sk,
          sum(ws_quantity) ws_qty,
          sum(ws_wholesale_cost) ws_wc,
          sum(ws_sales_price) ws_sp
   FROM web_sales
   LEFT JOIN web_returns ON wr_order_number=ws_order_number
   AND ws_item_sk=wr_item_sk
   JOIN date_dim ON ws_sold_date_sk = d_date_sk
   WHERE wr_order_number IS NULL
   GROUP BY d_year,
            ws_item_sk,
            ws_bill_customer_sk ),
     cs AS
  (SELECT d_year AS cs_sold_year,
          cs_item_sk,
          cs_bill_customer_sk cs_customer_sk,
          sum(cs_quantity) cs_qty,
          sum(cs_wholesale_cost) cs_wc,
          sum(cs_sales_price) cs_sp
   FROM catalog_sales
   LEFT JOIN catalog_returns ON cr_order_number=cs_order_number
   AND cs_item_sk=cr_item_sk
   JOIN date_dim ON cs_sold_date_sk = d_date_sk
   WHERE cr_order_number IS NULL
   GROUP BY d_year,
            cs_item_sk,
            cs_bill_customer_sk ),
     ss AS
  (SELECT d_year AS ss_sold_year,
          ss_item_sk,
          ss_customer_sk,
          sum(ss_quantity) ss_qty,
          sum(ss_wholesale_cost) ss_wc,
          sum(ss_sales_price) ss_sp
   FROM store_sales
   LEFT JOIN store_returns ON sr_ticket_number=ss_ticket_number
   AND ss_item_sk=sr_item_sk
   JOIN date_dim ON ss_sold_date_sk = d_date_sk
   WHERE sr_ticket_number IS NULL
   GROUP BY d_year,
            ss_item_sk,
            ss_customer_sk )
SELECT ss_sold_year,
       ss_item_sk,
       ss_customer_sk,
       round((ss_qty*1.00)/(coalesce(ws_qty,0)+coalesce(cs_qty,0)),2) ratio,
       ss_qty store_qty,
       ss_wc store_wholesale_cost,
       ss_sp store_sales_price,
       coalesce(ws_qty,0)+coalesce(cs_qty,0) other_chan_qty,
       coalesce(ws_wc,0)+coalesce(cs_wc,0) other_chan_wholesale_cost,
       coalesce(ws_sp,0)+coalesce(cs_sp,0) other_chan_sales_price
FROM ss
LEFT JOIN ws ON (ws_sold_year=ss_sold_year
                 AND ws_item_sk=ss_item_sk
                 AND ws_customer_sk=ss_customer_sk)
LEFT JOIN cs ON (cs_sold_year=ss_sold_year
                 AND cs_item_sk=ss_item_sk
                 AND cs_customer_sk=ss_customer_sk)
WHERE (coalesce(ws_qty,0)>0
       OR coalesce(cs_qty, 0)>0)
  AND ss_sold_year=2000
ORDER BY ss_sold_year,
         ss_item_sk,
         ss_customer_sk,
         ss_qty DESC,
         ss_wc DESC,
         ss_sp DESC,
         other_chan_qty,
         other_chan_wholesale_cost,
         other_chan_sales_price,
         ratio
LIMIT 100;