[subquery_factoring_clause] 
SELECT [hint] [ { DISTINCT | UNIQUE } | ALL ] select_list 
FROM table_reference [, table_reference]... 
[WHERE condition]
[{ hierarchical_query_clause | group_by_clause } 
   [ hierarchical_query_clause | group_by_clause ]...]
[ UNION | UNION ALL | INTERSECT | MINUS } ( subquery )] 
[order_by_clause]

For information on the symbols and conventions of Backus-Naur Form (BNF) syntax, see Appendix A.