Robert Haas <robertmh...@gmail.com> writes: > As to why it causes us pain, I don't have a full picture of that. > Target list construction is one problem: we build all these target > lists for intermediate notes during planning and they're long enough > -- if the user has a bunch of columns -- and planning is cheap enough > for some queries that the sheer time to construct the list shows up > noticeably in profiles.
Well, the tlist data structure is just about completely separate from the TupleTableSlot mechanisms. I'm more prepared to believe that we could improve on the former, though I don't have any immediate ideas about how. regards, tom lane