Tom Lane wrote: > "Kevin Grittner" <kevin.gritt...@wicourts.gov> writes: >> You do, but it's been pretty rare in my experience, and we're >> considering alternatives which give a lot less flexibility that this. > > I dunno about "considering". We've already wasted vastly more time on > this than it's worth. AFAIR there has never been one single user > request for the ability to partially constrain join order. I think we > should do an enable_join_ordering boolean and quit wasting brainpower on > the issue.
I think I've found it useful in the past[1], but I also think we already have a way to give postgres such hints using subselects and "offset 0". Instead of SAP-DB's > select * from (t1 join t2 on <whatever>) join t3 on <whatever>; ISTM we can already do > select * from (select t1 join t2 on <whatever> offset 0) as a join t3 on > <whatever>; which seems like a reasonably way of hinting which parenthesis can be reordered and which can't. Would these new proposals give (guc's or syntax hacks) anything that I can't already do? [1] http://archives.postgresql.org/pgsql-performance/2007-12/msg00088.php -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
