Re: partitioned tables referenced by FKs

On Fri, Nov 2, 2018 at 7:42 PM Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>
wrote:

> Here's a patch to allow partitioned tables to be referenced by foreign
> keys. Current state is WIP, but everything should work; see below for
> the expected exception.
>
> The design is very simple: have one pg_constraint row for each partition
> on each side, each row pointing to the topmost table on the other side;
> triggers appear on each leaf partition (and naturally they don't appear
> on any intermediate partitioned table).
>

This is an important and much needed feature!

Based on my extremely naive reading of this code, I have two perhaps
equally naive questions:

1. it seems that we will continue to to per-row RI checks for inserts and
updates. However, there already exists a bulk check in RI_Initial_Check().
Could we modify this bulk check to do RI checks on a per-statement basis
rather than a per-row basis?

2. If #1 is possible, is the overhead of transitions tables too great for
the single-row case?