Robert Haas <robertmh...@gmail.com> writes: > Yay! I'm excited about this, particularly the possible "pipelining" > stuff, where you can do WITH (DELETE .. RETURNING ..) INSERT ... and > have it be like cool and fast and stuff.
> Or at least I hope you can do that. It's gonna need some work yet. As things stand, the tuples are indeed pipelined through, but the CteScan nodes *also* stash them aside into tuplestores, just in case somebody demands a rescan. Fixing that will require revisiting the exec flags (EXEC_FLAG_REWIND etc). We don't currently distinguish "it's unlikely you'll have to rescan" from "you're guaranteed not to have to rescan", but a CteScan that's covering a ModifyTable has to know the latter to not have to keep hold of copies of the RETURNING tuples. It might be a small enough change to do after alpha starts, but I don't have time for it right now. regards, tom lane -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers