SELECT channels.channel_desc, calendar_month_desc,  
       countries.country_iso_code, 
       TO_CHAR(SUM(amount_sold), '9,999,999,999') SALES$ 
FROM SH.sales, SH.customers, SH.times, SH.channels, SH.countries 
WHERE sales.time_id=times.time_id  
  AND sales.cust_id=customers.cust_id  
  AND customers.country_id = countries.country_id 
  AND sales.channel_id = channels.channel_id  
  AND channels.channel_desc IN ('Direct Sales', 'Internet')  
  AND times.calendar_month_desc IN ('2000-09', '2000-10')  
  AND countries.country_iso_code IN ('GB', 'US') 
GROUP BY  
  ROLLUP(channels.channel_desc, calendar_month_desc, countries.country_iso_code)