Issue #3170 resolved
use of singletons in 0.9 causes non-intuitive folding of constants
from sqlalchemy import select, null from sqlalchemy.sql.elements import Null print select([null(), null()]) print select([Null(), Null()])
SELECT NULL AS anon_1 SELECT NULL AS anon_1, NULL AS anon_2
this is due to the singleton.
it's totally a regression, so this is critical that something is figured out.