Marko Tiikkaja <marko.tiikk...@cs.helsinki.fi> writes: > On 2010-11-08 7:26 PM +0200, Tom Lane wrote: >> The alternative is to artificially serialize the DML CTEs, which >> while it does have some advantages doesn't seem like a win overall.
> We've discussed this before and the consensus was that as long as we > don't change the results, we can optimize the materialization away. No, because the problem is mainly about what might happen if user-defined functions choose to look at the target tables. We can't really tell what triggers are going to do, to take one item that the planner has no access to. I think we have to decide up front which implementation behavior it's going to be, and if we go with serialized queries, we'll be stuck with that. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers