Re: set-valued function called in context that cannot accept a set

On Mar 6, 2009, at 3:27 PM, Raymond O'Donnell wrote:

> When a function returns SETOF something, you need to treat it as if it
> were a table, thus:
>
> select * from unnest2(...);

Except that isn't true if the function is written in C.

CREATE OR REPLACE FUNCTION unnest(anyarray)
RETURNS SETOF anyelement AS 'unnest'
LANGUAGE 'C' IMMUTABLE;

SELECT unnest(...);

works just fine using the above defined C function.

So my question is really, what's the difference and why doesn't this
work with PL/PGSQL functions?

eric