On 2/20/15 3:09 PM, Tomas Vondra wrote: > The 'combine' function gets two such 'state' values, while transition > gets 'state' + next value.
I think the combine function is not actually a property of the aggregate, but a property of the transition function. If two aggregates have the same transition function, they will also have the same combine function. The combine function really just says, how do you combine two series of these function calls. Say maybe this should be put into pg_proc instead. (Or you make the transition functions transition operators and put the info into pg_operator instead, which is where function call optimization information is usually kept.) -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
