2008/12/26 Ivan Sergio Borgonovo <mail@xxxxxxxxxxxxxxx>: > On Fri, 26 Dec 2008 15:46:48 +0100 > "Pavel Stehule" <pavel.stehule@xxxxxxxxx> wrote: > >> count has only one argument, > > then what was changed between 8.1 and 8.2 to change the docs? > None of the functions listed in: > http://www.postgresql.org/docs/8.2/static/functions-aggregate.html > seems to support > aggregate(distinct exp [,exp]) http://www.postgresql.org/docs/8.2/interactive/functions-aggregate.html http://www.postgresql.org/docs/8.2/interactive/functions-aggregate.html#FUNCTIONS-AGGREGATE-STATISTICS-TABLE > > Does the change reflect the change in the possibility to write user > defined aggregates that support more then one distinct expression? CREATE AGGREGATE name ( input_data_type [ , ... ] ) ( SFUNC = sfunc, STYPE = state_data_type [ , FINALFUNC = ffunc ] [ , INITCOND = initial_condition ] [ , SORTOP = sort_operator ] ) you are able to write multi param aggregates. regards Pavel Stehule > > The first thing that comes to my mind to emulate > count(distinct a,b) > would be to > > create table test.dist (a int, b int); > insert into test.dist values(1,0); > insert into test.dist values(1,0); > insert into test.dist values(1,1); > insert into test.dist values(0,0); > select count(*) from (select distinct a,b from test.dist ) a; > > but still I can't think of anything that would work with > aggregate(distinct a,b) > not just count. > > -- > Ivan Sergio Borgonovo > http://www.webthatworks.it > > > -- > Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-general > -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
