Re: Partitioning vs ON CONFLICT

On Fri, Mar 31, 2017 at 5:33 PM, Peter Geoghegan  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...

-- 
Robert Haas
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