Date: Mon, 13 Dec 2021 07:48:30 -0600
From: Justin Pryzby <pryzby@telsasoft.com>
To: Tomas Vondra <tomas.vondra@enterprisedb.com>
Cc: Zhihong Yu <zyu@yugabyte.com>,
	Jaime Casanova <jcasanov@systemguards.com.ec>,
	pgsql-hackers@postgresql.org
Subject: Re: extended stats on partitioned tables
Message-ID: <20211213134830.GS17618@telsasoft.com>
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On Sun, Dec 12, 2021 at 10:29:39PM +0100, Tomas Vondra wrote:
> > In your 0003 patch, the "if inh: break" isn't removed from examine_variable(),
> > but the corresponding thing is removed everywhere else.
> 
> Ah, you're right. And it wasn't updated in the 0002 patch either - it
> should do the relkind check too, to allow partitioned tables. Fixed.

I think you fixed it in 0002 (thanks) but still wasn't removed from 0003?

In these comments:
+        * When dealing with regular inheritance trees, ignore extended stats
+        * (which were built without data from child rels, and thus do not
+        * represent them). For partitioned tables data from partitions are
+        * in the stats (and there's no data in the non-leaf relations), so
+        * in this case we do consider extended stats.

I suggest to add a comment after "For partitioned tables".

-- 
Justin