On Tue, Dec 15, 2009 at 10:28:49PM +0100, Pavel Stehule wrote: > Hello > > I am looking on new feature - ORDER clause in aggregate, and I thing, > so we are able to effectively implement some non standard, but well > known aggregates. > > a) function median - it is relative frequent request - with usually > slow implementation
Makes a lot of sense. I suspect we'll have to provide several different medians, as there are several precise, useful, and conflicting definitions. Some examples below: http://www.simple-talk.com/sql/t-sql-programming/median-workbench/ > b) function listagg (it is analogy of group_concat from MySQL) - it > should simplify report generating and some other This is redundant, as it's equivalent to array_to_string(array_agg()). If it's done as syntactic sugar over that, it's fine. If it's a separate implementation, it's a bad idea. Probably best as an optional module of some kind. Cheers, David. -- David Fetter <da...@fetter.org> http://fetter.org/ Phone: +1 415 235 3778 AIM: dfetter666 Yahoo!: dfetter Skype: davidfetter XMPP: david.fet...@gmail.com iCal: webcal://www.tripit.com/feed/ical/people/david74/tripit.ics Remember to vote! Consider donating to Postgres: http://www.postgresql.org/about/donate -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
