Re: HISTORY updated, 7.3 branded

Tom Lane wrote:
> C functions have always been able to return sets too; you don't honestly
> think that a SQL function can do something a C function can't, do you?

The original dblink is an example.

>
> There are really two independent improvements here: one is the ability
> for plpgsql functions to return sets, and the other is a group of
> improvements that make it easier to use a function-returning-set,
> independently of what language it's written in.
>

As an example, although you *could* return a composite type before, it
was almost useless, because what you actually got returned to you was a
pointer:

test=# create function get_foo() returns setof foo as 'select * from
foo' language sql;
CREATE
test=# select get_foo();
get_foo
-----------
137867648
137867648
137867648
(3 rows)

In order to get the individual columns, you had to do:

test=# select f1(get_foo()), f2(get_foo()), f3(get_foo());
f1 | f2 | f3
----+----+-----
1 | 1 | abc
1 | 2 | def
2 | 1 | ghi
(3 rows)

Pretty ugly, but it did work.

What about this:

Functions returning multiple rows and/or multiple columns are
now much easier to use than before. You can call such a
"table function" in the SELECT FROM clause, treating its output
like a table. Also, plpgsql functions can now return sets.

Joe