Mark Hills <Mark(dot)Hills(at)framestore(dot)com> writes:
> One of our most-used queries performs poorly (taking over 2 seconds) and a
> tiny amount of refactoring shows it can be fast (less than 1ms) by
> transforming the OR case (which spans two tables) into a UNION.
I'd suggest going with the UNION. We are unlikely to make the planner
look for such cases, because usually such a transformation would be a
net loss. It seems like rather a corner case that it's a win even on
your example.
regards, tom lane