Viktor Bojović <viktor.bojovic@gmail.com> writes:
> I tried to write this part below, but something is wrong (ERROR: function
> grafika.pov_sphere(character varying, numeric, numeric, numeric, numeric,
> character varying) does not exist) so I wanted to ask if someone knows how
> to solve this problem.
Well, it's right: you didn't create such a function. The aggregate
transition function has to take the state datatype as its first
argument. You can't just plug these two randomly-chosen functions
into an aggregate definition and expect the system to intuit what you
want done. I think what you actually need is a transition function
that works something like
if ($1 is null) return agg_pov_sphere($2,$3,...);else return concat($1, agg_pov_sphere($2,$3,...));
regards, tom lane