On Thu, Sep 12, 2019 at 11:35 PM Antonin Houska <a...@cybertec.at> wrote:
> Richard Guo <ri...@pivotal.io> wrote: > > > On Wed, Sep 11, 2019 at 3:25 PM Antonin Houska <a...@cybertec.at> > > wrote: > > > > > > Nevertheless, I don't know how to overcome the problems that I > > mentioned > > upthread. > > > > > > Do you mean the problem "the WHERE clause of the subquery didn't > > participate in the SEMI JOIN evaluation"? Good news is it has been > > fixed > > by commit 043f6ff0 as I mentioned upthread. > > Do you say that my old patch (rebased) no longer breaks the regression > tests? > I think so. > > (I noticed your other email in the thread which seems to indicate that > you're > no lo longer interested to work on the feature, but asking out of > curiosity.) > Tom pointed out that even if we pull up the subquery with the help of LATERAL, we cannot make sure we will end up with a better plan, since LATERAL pretty much constrains things to use a nestloop. Hmm, I think what he said makes sense. Thanks Richard
