Re: Partitioning vs ON CONFLICT

On Fri, Mar 31, 2017 at 11:44 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> On Fri, Mar 31, 2017 at 5:33 PM, Peter Geoghegan <pg(at)bowt(dot)ie> wrote:
>> In my opinion, for the very limited ON CONFLICT DO NOTHING + no
>> inference specification case, the implementation should not care about
>> the presence or absence of unique indexes within or across partitions.
>
> Hmm. That's an interesting point. The documentation says:
>
> ON CONFLICT can be used to specify an alternative action to raising a
> unique constraint or exclusion constraint violation error.
>
> And, indeed, you could get an unique constraint or exclusion error
> because of an index on the child even though it's not global to the
> partitioning hierarchy. So maybe we can support this after all, but
> having messed it up once, I'm inclined to think we should postpone
> this to v11, think it over some more, and try to make sure that our
> second try doesn't crash...

Naturally this means that the partitioning work will be reverted as
well, since we have a consensus that new features shouldn't make
preexisting ones worse. It's a shame, since I was really hoping to see
it in 10.0.

♜