WITH
  web_v1 AS (
   SELECT
     "ws_item_sk" "item_sk"
   , "d_date"
   , "sum"("sum"("ws_sales_price")) OVER (PARTITION BY "ws_item_sk" ORDER BY "d_date" ASC ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) "cume_sales"
   FROM
     web_sales
   , date_dim
   WHERE ("ws_sold_date_sk" = "d_date_sk")
      AND ("d_month_seq" BETWEEN 1200 AND (1200 + 11))
      AND ("ws_item_sk" IS NOT NULL)
   GROUP BY "ws_item_sk", "d_date"
) 
, store_v1 AS (
   SELECT
     "ss_item_sk" "item_sk"
   , "d_date"
   , "sum"("sum"("ss_sales_price")) OVER (PARTITION BY "ss_item_sk" ORDER BY "d_date" ASC ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) "cume_sales"
   FROM
     store_sales
   , date_dim
   WHERE ("ss_sold_date_sk" = "d_date_sk")
      AND ("d_month_seq" BETWEEN 1200 AND (1200 + 11))
      AND ("ss_item_sk" IS NOT NULL)
   GROUP BY "ss_item_sk", "d_date"
) 
SELECT *
FROM
  (
   SELECT
     "item_sk"
   , "d_date"
   , "web_sales"
   , "store_sales"
   , "max"("web_sales") OVER (PARTITION BY "item_sk" ORDER BY "d_date" ASC ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) "web_cumulative"
   , "max"("store_sales") OVER (PARTITION BY "item_sk" ORDER BY "d_date" ASC ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) "store_cumulative"
   FROM
     (
      SELECT
        (CASE WHEN ("web"."item_sk" IS NOT NULL) THEN "web"."item_sk" ELSE "store"."item_sk" END) "item_sk"
      , (CASE WHEN ("web"."d_date" IS NOT NULL) THEN "web"."d_date" ELSE "store"."d_date" END) "d_date"
      , "web"."cume_sales" "web_sales"
      , "store"."cume_sales" "store_sales"
      FROM
        (web_v1 web
      FULL JOIN store_v1 store ON ("web"."item_sk" = "store"."item_sk")
         AND ("web"."d_date" = "store"."d_date"))
   )  x
)  y
WHERE ("web_cumulative" > "store_cumulative")
ORDER BY "item_sk" ASC, "d_date" ASC
LIMIT 100
;