text: /*Verwendung des ALL-Operators*/
  /*https://www.oracletutorial.com/oracle-basics/oracle-all/*/
  
  /*Return values greater than the maximum list_price of category 1*/
  SELECT product_name, list_price
  FROM products p1
  WHERE p1.list_price > ALL( SELECT p2.list_price
                             FROM products p2
                             WHERE category_id = 1 )
  ORDER BY product_name;
  
  
  /*Find the average list_price of each category*/
  SELECT category_id, ROUND(AVG(list_price),2) avg_list_price
  FROM products
  GROUP BY category_id
  ORDER BY category_id;
  
  /*Fin products with list_prices greater than the highest price of the average price list*/
  SELECT product_name, list_price
  FROM products
  WHERE list_price > ALL ( SELECT AVG(list_price)
                           FROM products
                           GROUP BY category_id )
  ORDER BY list_price;
  
  --SELECT MAX(list_price) FROM products WHERE category_id = 1                           
  