WITH
  all_sales AS (
   SELECT
     "d_year"
   , "i_brand_id"
   , "i_class_id"
   , "i_category_id"
   , "i_manufact_id"
   , "sum"("sales_cnt") "sales_cnt"
   , "sum"("sales_amt") "sales_amt"
   FROM
     (
      SELECT
        "d_year"
      , "i_brand_id"
      , "i_class_id"
      , "i_category_id"
      , "i_manufact_id"
      , ("cs_quantity" - COALESCE("cr_return_quantity", 0)) "sales_cnt"
      , ("cs_ext_sales_price" - COALESCE("cr_return_amount", DECIMAL '0.0')) "sales_amt"
      FROM
        (((catalog_sales
      INNER JOIN item ON ("i_item_sk" = "cs_item_sk"))
      INNER JOIN date_dim ON ("d_date_sk" = "cs_sold_date_sk"))
      LEFT JOIN catalog_returns ON ("cs_order_number" = "cr_order_number")
         AND ("cs_item_sk" = "cr_item_sk"))
      WHERE ("i_category" = 'Books')
UNION       SELECT
        "d_year"
      , "i_brand_id"
      , "i_class_id"
      , "i_category_id"
      , "i_manufact_id"
      , ("ss_quantity" - COALESCE("sr_return_quantity", 0)) "sales_cnt"
      , ("ss_ext_sales_price" - COALESCE("sr_return_amt", DECIMAL '0.0')) "sales_amt"
      FROM
        (((store_sales
      INNER JOIN item ON ("i_item_sk" = "ss_item_sk"))
      INNER JOIN date_dim ON ("d_date_sk" = "ss_sold_date_sk"))
      LEFT JOIN store_returns ON ("ss_ticket_number" = "sr_ticket_number")
         AND ("ss_item_sk" = "sr_item_sk"))
      WHERE ("i_category" = 'Books')
UNION       SELECT
        "d_year"
      , "i_brand_id"
      , "i_class_id"
      , "i_category_id"
      , "i_manufact_id"
      , ("ws_quantity" - COALESCE("wr_return_quantity", 0)) "sales_cnt"
      , ("ws_ext_sales_price" - COALESCE("wr_return_amt", DECIMAL '0.0')) "sales_amt"
      FROM
        (((web_sales
      INNER JOIN item ON ("i_item_sk" = "ws_item_sk"))
      INNER JOIN date_dim ON ("d_date_sk" = "ws_sold_date_sk"))
      LEFT JOIN web_returns ON ("ws_order_number" = "wr_order_number")
         AND ("ws_item_sk" = "wr_item_sk"))
      WHERE ("i_category" = 'Books')
   )  sales_detail
   GROUP BY "d_year", "i_brand_id", "i_class_id", "i_category_id", "i_manufact_id"
) 
SELECT
  "prev_yr"."d_year" "prev_year"
, "curr_yr"."d_year" "year"
, "curr_yr"."i_brand_id"
, "curr_yr"."i_class_id"
, "curr_yr"."i_category_id"
, "curr_yr"."i_manufact_id"
, "prev_yr"."sales_cnt" "prev_yr_cnt"
, "curr_yr"."sales_cnt" "curr_yr_cnt"
, ("curr_yr"."sales_cnt" - "prev_yr"."sales_cnt") "sales_cnt_diff"
, ("curr_yr"."sales_amt" - "prev_yr"."sales_amt") "sales_amt_diff"
FROM
  all_sales curr_yr
, all_sales prev_yr
WHERE ("curr_yr"."i_brand_id" = "prev_yr"."i_brand_id")
   AND ("curr_yr"."i_class_id" = "prev_yr"."i_class_id")
   AND ("curr_yr"."i_category_id" = "prev_yr"."i_category_id")
   AND ("curr_yr"."i_manufact_id" = "prev_yr"."i_manufact_id")
   AND ("curr_yr"."d_year" = 2002)
   AND ("prev_yr"."d_year" = (2002 - 1))
   AND ((CAST("curr_yr"."sales_cnt" AS DECIMAL(17,2)) / CAST("prev_yr"."sales_cnt" AS DECIMAL(17,2))) < DECIMAL '0.9')
ORDER BY "sales_cnt_diff" ASC, "sales_amt_diff" ASC
LIMIT 100
;