Re: The plan for FDW-based sharding

On 2 March 2016 at 03:02, Bruce Momjian <bruce(at)momjian(dot)us> wrote:

> On Tue, Mar 1, 2016 at 07:56:58PM +0100, Petr Jelinek wrote:
> > Note that I am not saying that other discussed approaches are any
> > better, I am saying that we should know approximately what we
> > actually want and not just beat FDWs with a hammer and hope sharding
> > will eventually emerge and call that the plan.
>
> I will say it again --- FDWs are the only sharding method I can think of
> that has a chance of being accepted into Postgres core. It is a plan,
> and if it fails, it fails. If is succeeds, that's good. What more do
> you want me to say?

That you won't push it too hard if it works, but works badly, and will be
prepared to back off on the last steps despite all the lead-up
work/time/investment you've put into it.

If FDW-based sharding works, I'm happy enough, I have no horse in this
race. If it doesn't work I don't much care either. What I'm worried about
is it if works like partitioning using inheritance works - horribly badly,
but just well enough that it's served as an effective barrier to doing
anything better.

That's what I want to prevent. Sharding that only-just-works and then stops
us getting anything better into core.

--
Craig Ringer http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services