--q2.sql--

 WITH wscs as
 (SELECT sold_date_sk, sales_price
  FROM (SELECT ws_sold_date_sk sold_date_sk, ws_ext_sales_price sales_price
        FROM web_sales
        UNION ALL
       SELECT cs_sold_date_sk sold_date_sk, cs_ext_sales_price sales_price
        FROM catalog_sales) x),
 wswscs AS
 (SELECT d_week_seq,
        sum(case when (d_day_name='Sunday') then sales_price else null end) sun_sales,
        sum(case when (d_day_name='Monday') then sales_price else null end) mon_sales,
        sum(case when (d_day_name='Tuesday') then sales_price else  null end) tue_sales,
        sum(case when (d_day_name='Wednesday') then sales_price else null end) wed_sales,
        sum(case when (d_day_name='Thursday') then sales_price else null end) thu_sales,
        sum(case when (d_day_name='Friday') then sales_price else null end) fri_sales,
        sum(case when (d_day_name='Saturday') then sales_price else null end) sat_sales
 FROM wscs, date_dim
 WHERE d_date_sk = sold_date_sk
 GROUP BY d_week_seq)
 SELECT d_week_seq1
       ,round(sun_sales1/sun_sales2,2)
       ,round(mon_sales1/mon_sales2,2)
       ,round(tue_sales1/tue_sales2,2)
       ,round(wed_sales1/wed_sales2,2)
       ,round(thu_sales1/thu_sales2,2)
       ,round(fri_sales1/fri_sales2,2)
       ,round(sat_sales1/sat_sales2,2)
 FROM
 (SELECT wswscs.d_week_seq d_week_seq1
        ,sun_sales sun_sales1
        ,mon_sales mon_sales1
        ,tue_sales tue_sales1
        ,wed_sales wed_sales1
        ,thu_sales thu_sales1
        ,fri_sales fri_sales1
        ,sat_sales sat_sales1
  FROM wswscs,date_dim
  WHERE date_dim.d_week_seq = wswscs.d_week_seq AND d_year = 2001) y,
 (SELECT wswscs.d_week_seq d_week_seq2
        ,sun_sales sun_sales2
        ,mon_sales mon_sales2
        ,tue_sales tue_sales2
        ,wed_sales wed_sales2
        ,thu_sales thu_sales2
        ,fri_sales fri_sales2
        ,sat_sales sat_sales2
  FROM wswscs, date_dim
  WHERE date_dim.d_week_seq = wswscs.d_week_seq AND d_year = 2001 + 1) z
 WHERE d_week_seq1=d_week_seq2-53
 ORDER BY d_week_seq1;
            
