Re: Partition-wise join for join between (declaratively) partitioned tables

On Mon, Mar 20, 2017 at 9:44 AM, Ashutosh Bapat
<ashutosh(dot)bapat(at)enterprisedb(dot)com> wrote:
> Right. If we could use parent Vars to indicate parent Var or child Var
> depending upon the context, a lot of memory issues would be solved; we
> wouldn't need to translate a single expression. But I think that's not
> straight forward. I have been thinking about some kind of polymorphic
> Var node, but it seems a lot more invasive change. Although, if we
> could get something like that, we would save a huge memory. :)

Yes, that's why I'm interested in exploring that approach once the
basic framework is in place here.

> I am wondering whether we need to change
> calc_non_nestloop_required_outer() similar to
> calc_nestloop_required_outer() just to keep their signatures in sync.

I haven't looked at the patch, but I don't think you need to worry about that.

> Should I work on completing reparamterized_path_by_child() to support
> all kinds of paths?

Yes, or at the very least all scans, like reparameterize_path() already does.

--
Robert Haas
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