Florian Pflug wrote:
> On Feb17, 2011, at 01:14 , Oliver Jowett wrote:
>> 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.
>
> There's no sane way to do that, I fear. You could of course look up the
> function definition in the catalog before actually calling it, but with
> overloading and polymorphic types finding the right pg_proc entry seems
> awfully complex.
>
> Your best option is probably to just document this caveat...
Well, the JDBC driver does know how many OUT parameters there are before
execution happens, so it could theoretically do something different for
1 OUT vs. many OUT parameters.
The problem is that currently the translation of the JDBC "{ call }"
escape happens early on, well before we know which parameters are OUT
parameters. Moving that translation later is, at best, tricky, so I was
hoping there was one query form that would handle all cases.
Oliver