return next in recursive function

I have found that when I use the RETURN NEXT command in recursive function,
not all records are returned. The only records I can obtain from function
are records from the highest level of recursion. Does exist some
work-around?

Thanks
Petr Bravenec

example:
create table foo (
uid int4,
pid int4
);

insert into foo values (1,0);
insert into foo values (2,0);
insert into foo values (3,0);
insert into foo values (4,1);
insert into foo values (5,1);
insert into foo values (6,5);
insert into foo values (7,5);
insert into foo values (8,2);

create or replace function foo (integer)
returns setof foo as '
declare pid alias for $1;
declare rec RECORD;
BEGIN
FOR rec in select * from foo
where foo.pid=pid LOOP
return next rec;
raise warning ''uid=% pid=%'',rec.uid,rec.pid;
select into rec * from foo (rec.uid);
END LOOP;
return null;
end;
' language 'plpgsql';

select * from foo(0);

The output:
WARNING: uid=1 pid=0
WARNING: uid=4 pid=1
WARNING: uid=5 pid=1
WARNING: uid=6 pid=5
WARNING: uid=7 pid=5
WARNING: uid=2 pid=0
WARNING: uid=8 pid=2
WARNING: uid=3 pid=0
uid | pid
-----+-----
1 | 0
2 | 0
3 | 0

The warnings show how the output should look.

PgSQL version 7.3.4

--

email: pbravenec(at)solartec(dot)cz
telefon: 777 566 384
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