2009/11/9 Andrew Gierth <and...@tao11.riddles.org.uk>: >>>>>> "Heikki" == Heikki Linnakangas <heikki.linnakan...@enterprisedb.com> >>>>>> writes: > > Heikki> Yeah, we need the reinitialization support to handle the generic > case. > > Heikki> One idea is to take a copy of the state datum after each row. > > Some existing aggregates, notably array_agg, rely on the assumption > that this never happens.
I'm carefully coding to keep the existing behavior that when frame start is UNBOUNDED PRECEDING aggregate state is cached. I don't see how the copied state will help in other frame types, but is it rather than that? We assume the frame starting and ending boundary never goes back. Regards, -- Hitoshi Harada -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
