Joe,
> We are attempting to move a couple of systems from Oracle to Postgres but
can not do so without application rewrites due to the current use of views
with UNIONs and the criticality of the performances of these views.
>
> I was wondering if a decision has been made on the optimization with the
UNION clause in views. There are many documents in the SQL archive showing
that the "push down" is not occuring and thus the use of UNION's in views is
limited to case where the data set is small or performance is not a
consideration. I also looked through the TODO list and didn't see anything
(of course I could have missed references).
I'd take this up on PGSQL-HACKERS. The UNION VIEW optimization, last I
checked, was stalled mainly because nobody wanted to work on it. Maybe you
can?
--
-Josh BerkusAglio Database SolutionsSan Francisco