Pavel Stehule:
The session variables can be used in queries, but should be used in
PL/pgSQL expressions, and then the mandatory usage in FROM clause will
do lot of problems and unreadable code like
DO $$
BEGIN
RAISE NOTICE '% %', (SELECT x FROM x), (SELECT a,b FROM y);
END
$$
This requirement does variables unusable in PL
I already proposed earlier to only require listing them in FROM when
there is actually a related FROM.
In this case you could still write:
RAISE NOTICE '% %', x, (SELECT a,b FROM y);
(assuming only x is a variable here)
Best,
Wolfgang
