Date: Thu, 19 Apr 2018 16:40:17 -0300
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
Cc: Pavan Deolasee <pavan.deolasee@gmail.com>,
	Etsuro Fujita <fujita.etsuro@lab.ntt.co.jp>,
	Andres Freund <andres@anarazel.de>,
	Pg Hackers <pgsql-hackers@postgresql.org>,
	Peter Geoghegan <pg@bowt.ie>
Subject: Re: ON CONFLICT DO UPDATE for partitioned tables
Message-ID: <20180419194017.xeqvcndqsslojqk2@alvherre.pgsql>
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Alvaro Herrera wrote:
> Amit Langote wrote:
> 
> > Yeah, I too have wondered in the past what it would take to make
> > equalTupDescs() return true for parent and partitions.  Maybe we can make
> > it work by looking a bit harder than I did then.
> 
> How about simply relaxing the tdtypeid test from equalTupleDescs?  I
> haven't looked deeply but I think just checking whether or not both are
> RECORDOID might be sufficient, for typecache purposes.

After looking at the code, I'm a bit nervous about doing this, because I
don't fully understand what is going on in typcache, and what is the
HeapTupleHeaderGetTypeId macro really doing.  I'm afraid that if we
confuse a table's tupdesc with one of its partition's , something
entirely random might end up happening.

Maybe this is completely off-base, but if so I'd like to have to proof.
So I'm thinking of reverting that patch instead per your patch.

While composing this we got emails from Robert and Peter G suggesting
the same too, so consider it done.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services