Re: [HACKERS] Fwd: Weird issues when reading UDT from stored function

On 17/02/11 04:23, Tom Lane wrote:
> Florian Pflug <fgp@phlo.org> writes:
>> Hm, I've browsed through the code and it seems that the current behaviour
>> was implemented on purpose.
>
> Yes, it's 100% intentional.  The idea is to allow function authors to
> use OUT-parameter notation (in particular, the convention of assigning
> to a named variable to set the result) without forcing them into the
> overhead of returning a record when all they want is to return a scalar.
> So a single OUT parameter is *supposed* to work just like a function
> that does "returns whatever" without any OUT parameters.
>
> Even if you think this was a bad choice, which I don't, it's far too
> late to change it.

Any suggestions about how the JDBC driver can express the query to get
the behavior that it wants? Specifically, the driver wants to call a
particular function with N OUT or INOUT parameters (and maybe some other
IN parameters too) and get a resultset with N columns back.

The current approach is to say "SELECT * FROM f(params) AS RESULT" which
works in all cases *except* for the case where there is exactly one OUT
parameter and it has a record/UDT type.

Oliver