However, when I use the following, I can fetch the values from the table / view
 #$SQL_query = qq {SELECT display_order, name, id_parent_category from CATEGORY ORDER BY DISPLAY_ORDER };
    #$SQL_query = qq {SELECT display_order, name, id_parent_category from MY_VIEW };

I tried creating a oracle view for the SQL query which has the outer join and used the following query but still I could not display the values from the array.
    #$SQL_query = qq {SELECT * from VW_CATEGORIES};