Re: SQL procedures

On 10/31/17 14:23, Tom Lane wrote:
> Putting 0 in prorettype seems like a pretty bad idea.

It seemed like the natural thing to do, since we use a zero OID to
indicate "nothing" in many other places.

> Why not use VOIDOID for the prorettype value?

We need a way to distinguish functions that are callable by SELECT and
procedures that are callable by CALL.

> Or if there is some reason why "void" isn't the
> right pseudotype, maybe you should invent a new one, analogous to the
> "trigger" and "event_trigger" pseudotypes.

I guess that would be doable, but I think it would make things more
complicated without any gain that I can see. In the case of the
pseudotypes you mention, those are the actual types mentioned in the
CREATE FUNCTION command. If we invented a new pseudotype, that would
run the risk of existing code creating nonsensical reverse compilations
like CREATE FUNCTION RETURNS PROCEDURE. Catalog queries using
prorettype == 0 would behave sensibly by default. For example, an inner
or outer join against pg_type would automatically make sense.

--
Peter Eisentraut http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services