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Date: Thu, 18 Jun 2026 10:49:38 -0500
From: Justin Pryzby <pryzby@telsasoft.com>
To: Alexander Korotkov <aekorotkov@gmail.com>
Cc: Pavel Borisov <pashkin.elfe@gmail.com>,
	Dmitry Koval <d.koval@postgrespro.ru>,
	Alexander Lakhin <exclusion@gmail.com>,
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	Tomas Vondra <tomas.vondra@enterprisedb.com>,
	Alvaro Herrera <alvherre@alvh.no-ip.org>
Subject: Re: Add SPLIT PARTITION/MERGE PARTITIONS commands
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On Thu, Jun 18, 2026 at 10:31:11AM +0300, Alexander Korotkov wrote:
> Pushed with your suggestions accepted.

Thanks.  When I went back to test this, I merged ~25 partitions that
were all on the same tablespace, but the merged table was created on the
default tablespace.

I tried again with default_tablespace set, but it was ignored.  I think
that's wrong.  It's good to follow the tablespace of the parent table,
but if it has no tablespace set, default_tablespace should be obeyed.
See surrounding logic in DefineRelation.

I see the docs say this:
+       <command>ALTER TABLE MERGE PARTITION</command> uses the partitioned
+       table itself as the template to construct the new partition.
+       The new partition will inherit the same table access method, persistence
+       type, and tablespace as the partitioned table.

-- 
Justin