Re: Joining with result of a plpgsql function

On Wed, 7 May 2008, Matthew T. O'Connor wrote:

> I have a pl/pgsql function, defined as:
>
> CREATE FUNCTION tms.get_tms_summary(id integer)
> RETURNS tms.tms_summary
>
> get_tms_summary returns a composite type, tms_summary, which is
> comprised of several numerics.
>
> What I would like to do is something like:
>
> select f.id, f.name, tms.get_tms_summary(f.id) from foo f;
>
> However this returns only three columns, the third of which is the
> entire complex data type in one column.
>
> I can do: select * from tms.get_tms_summary(99);
>
> But I would really like to be able to combine it with other data and get
> a result set that looked like:
>
> f.id, f.name, tms_summary.col1, tms_summary.col2 ...

Well I think
select f.id, f.name, (tms.get_tms_summary(f.id)).* from foo f;
would expand it out into separate columns, but I think that might also
call it multiple times. You might have better luck combining that with a
subquery like
select id, name, (summary).col1, (summary).col2, ... from
(select id, name, tms.get_tms_summary(f.id) as summary from foo) f;