Re: Postgres 11 procedures and result sets

On Mon, Oct 1, 2018 at 6:57 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Jan Kohnert <nospam001-lists@jan-kohnert.de> writes:
> > I have a question regarding the new stored procedures in Postgres 11 (I tested
> > beta4):
> > I'd like to know if it is somehow possible to get a (or possibly more) result
> > set from selects within the SP, as it is possible in MariaDB, MySQL, or SQL
> > Server.
>
> Not there as of v11, other than the refcursor approach you already know
> about.  We hope to have something nicer worked out for v12.  There
> are a lot of compatibility issues to sort through :-(

There are a few other ways of dealing with this.

If the data being returned isn't very large, you can stuff multiple
'datasets' into a single json.  I do this all the time today, with
functions.  Yet another tactic is to create temp tables (maybe ON
COMMIT DROP) and refer to those tables after calling the procedure.  I
would strongly consider this if the returned data was large and the
function/procedure was not called at a high rate (making system
catalog thrash in issue).  I would probably use these tactics,
especially the json style return, even after multi-result style
invocation were to drop.

merlin