2013/3/27 Tom Lane <tgl@xxxxxxxxxxxxx>: > Gavin Flower <GavinFlower@xxxxxxxxxxxxxxxxx> writes: >> The rule appears to be, >> where N_x & N_y are the number of entries returned for x & y: >> N_result = is the smallest positive integer that has N_x & N_y as factors. > > Right: if there are multiple set-returning functions in a SELECT list, > the number of rows you get is the least common multiple of their > periods. (See the logic in ExecTargetList that cycles the SRFs until > they all report "done" at the same time.) I guess there's some value > in this for the case where they all have the same period, but otherwise > it's kind of bizarre. It's been like that since Berkeley days though, > so I doubt we'll consider changing it now. Rather, it'll just be > quietly deprecated in favor of putting SRFs into FROM (with LATERAL > where needed). Thanks for the clarification, I was half-worried there was some fundamental set theory or something which had passed me by. Regards Ian Barwick -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
