Re: "SELECT ... FROM DUAL" is not quite as silly as it appears

Oh, one more thing: I see a warning without --enable-cassert in 
create_resultscan_plan, because rte is only used in an Assert.

src/backend/optimizer/plan/createplan.c:3457:17: warning: variable ‘rte’ 
set but not used [-Wunused-but-set-variable]
   RangeTblEntry *rte;

-- 
Alexander Kuzmenkov
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company