Re: Hybrid Hash/Nested Loop joins and caching results from subplans

Hi,

On 2020-05-20 23:44:27 +1200, David Rowley wrote:
> I've attached a patch which implements this. The new node type is
> called "Result Cache". I'm not particularly wedded to keeping that
> name, but if I change it, I only want to do it once. I've got a few
> other names I mind, but I don't feel strongly or confident enough in
> them to go and do the renaming.

I'm not convinced it's a good idea to introduce a separate executor node
for this. There's a fair bit of overhead in them, and they will only be
below certain types of nodes afaict. It seems like it'd be better to
pull the required calls into the nodes that do parametrized scans of
subsidiary nodes. Have you considered that?

Greetings,

Andres Freund