How to sort the result from string_agg() / order by string_agg on oracle 10g

 Hi there now day i will share how to order by string_agg() result
and here it's the simple code :

select string_agg(prod,' | ') FROM
  (SELECT product as prod FROM tblproducts ORDER BY product )MAIN;

source : https://stackoverflow.com/questions/24906826/how-to-sort-the-result-from-string-agg