Philippe Girolami <philippe.girolami@sensorly.com> writes:
> Hello,
> Using postgres 9.1.9, I have a view that uses a window function. I then query that view with a predicate on one of
thecolumns. Unfortunately, the predicate doesn't get pushed down into the view.
> Given that the predicate applies to a column that's being partitionned on, why wouldn't the optimizer push the
predicatedown ?
Because there is zero optimization around window functions right now.
It certainly isn't smart enough to decide that it'd be safe to push
down a constraint that only mentions partitioning columns.
regards, tom lane