Re: select into composite type / return

Gary Stainburn <gary(dot)stainburn(at)ringways(dot)co(dot)uk> writes:
> I have a function that takes 7 numerical inputs, performs calculations,
> and then returns a composite type.

> create type breakdown as
>   f1    numeric(9,2),
>   f2    numeric(9,2),
>   f3    numeric(9,2),
>   f4    numeric(9,2),
>   f5    numeric(9,2),
>   f6    numeric(9,2)
> );

> create function do_breakdown(
>   v1 numeric(9,2),
>   v2 numeric(9,2),
>   v3 numeric(9,2),
>   v4 numeric(9,2),
>   v5 numeric(9,2),
>   v6 numeric(9,2),
>   v7 numeric(9,2)
> ) returns breakdown as $$
> DECLARE
>   D breakdown;
> BEGIN
>  -- calculate breakdown
>   return D;
> END;
> $$
> LANGUAGE PLPGSQL;

> This works great, returning one row with the separate columns.

> I now want to set up another function which will take a key, retrieve
> the arguments from a table, and call the first function. The problem is
> that I can't get the syntax correct to return the composite type.  I
> have tried

> create function do_breakdown(key text) returns breakdown as $$
> DECLARE
>   v RECORD;
> BEGIN
>   select into v * from stored s where key s.key = key;
>   RETURN do_breakdown(v.f1,v.f2,v.f3,v.f4,v.f5,v.f6);
> END;
> $$
> LANGUAGE PLPGSQL;

> but it returns the whole thing as a single column.

AFAICS these two functions will have exactly the same output behavior,
ie returning a "breakdown" composite type. If they act differently
for you, either you are calling them in different ways or you made
a mistake somewhere. I can't help noticing that the RETURN in the
second function is calling a six-argument function, which is not the
one you showed first. Maybe that version of do_breakdown() returns
something different?

regards, tom lane