On Thu, Dec 5, 2019 at 05:45:24PM +1300, Thomas Munro wrote: > My patch set (rebased upthread) was extremely primitive, with no new > planner concepts, and added only a very simple new executor node > method: ExecReady(). Append used that to try to ask its children if > they'd like some time to warm up. By default, ExecReady() says "I > don't know what you're talking about, go away", but FDWs can provide > an implementation that says "yes, please call me again when this fd is > ready" or "yes, I am ready, please call ExecProc() now". It doesn't > deal with anything more complicated than that, and in particular it > doesn't work if there are extra planner nodes in between Append and > the foreign scan. (It also doesn't mix particularly well with > parallelism, as mentioned.) > > The reason I reposted this unambitious work is because Stephen keeps > asking me why we don't consider the stupidly simple thing that would > help with simple foreign partition-based queries today, instead of > waiting for someone to redesign the entire executor, because that's > ... really hard.
I agree with Stephen's request. We have been waiting for the executor rewrite for a while, so let's just do something simple and see how it performs. -- Bruce Momjian <br...@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + As you are, so once was I. As I am, so you will be. + + Ancient Roman grave inscription +
