Re: Removing INNER JOINs

On Wed, Dec 3, 2014 at 11:47 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> Atri Sharma <atri(dot)jiit(at)gmail(dot)com> writes:
> > On Wed, Dec 3, 2014 at 11:38 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> >> I think the right approach for now is to emulate the GEQO precedent as
> >> closely as possible. Build all the single-relation Paths the same as
> >> now, then do a join search over all the relations, then (if we've
> noticed
> >> that some joins are potentially removable) do another join search over
> >> just the nonremovable relations.
>
> > How about using geqo more liberally when replanning (decrease the number
> of
> > relations in join before geqo is hit?)
>
> This is going to be quite difficult enough without overcomplicating it.
> Or as a wise man once said, "premature optimization is the root of all
> evil". Get it working in the basic way and then see if improvement is
> necessary at all.
>
>
Sure, I can take a crack at it since I am working on a patch that does
require this alternative path approach. Let me try something and report my
experimental results.