From: Tom Lane <tgl@sss.pgh.pa.us>
To: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
cc: David Rowley <david.rowley@2ndquadrant.com>,
        Imai Yoshikazu <yoshikazu_i443@live.jp>,
        "jesper.pedersen@redhat.com" <jesper.pedersen@redhat.com>,
        "Imai,
    Yoshikazu" <imai.yoshikazu@jp.fujitsu.com>,
        Amit Langote <amitlangote09@gmail.com>,
        Alvaro Herrera <alvherre@2ndquadrant.com>,
        Robert Haas <robertmhaas@gmail.com>,
        Justin Pryzby <pryzby@telsasoft.com>,
        Pg Hackers <pgsql-hackers@postgresql.org>
Subject: Re: speeding up planning with partitions
In-reply-to: <23831.1553873385@sss.pgh.pa.us>
References: 
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 <53a80692-c68d-5e11-1014-6441b6e8ca5a@redhat.com>
 <BYAPR20MB22790FAFA860B03602A9A7B4BC420@BYAPR20MB2279.namprd20.prod.outlook.com>
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 <20519.1553288822@sss.pgh.pa.us> <15573.1553639191@sss.pgh.pa.us>
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 <19663.1553749401@sss.pgh.pa.us> <2a531b7c-8ced-f868-2e!
 f2-5cf33b92ef0f@lab.ntt.co.jp> <23856.1553812684@sss.pgh.pa.us>
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 <d807e9fd-2e4c-6910-ade0-1a7e23c706a1@lab.nt!
 t.co.jp> <23831.1553873385@sss.pgh.pa.us>
Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
	message dated "Fri, 29 Mar 2019 11:29:45 -0400"
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Date: Fri, 29 Mar 2019 12:31:09 -0400
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I wrote:
> Amit Langote <Langote_Amit_f8@lab.ntt.co.jp> writes:
>> About the XXX: I think resetting inh flag is unnecessary, so we should
>> just remove the line.

> Possibly.  I hadn't had time to follow up the XXX annotation.

Now I have ...

Yeah, it seems we can just drop that and leave the flag alone.  We'll
end up running through set_append_rel_size and finding no relevant
AppendRelInfos, but that's not going to take long enough to be a problem.
It seems better to have the principle that rte->inh doesn't change after
subquery_planner's initial scan of the rtable, so I'll make it so.

>> If we do that, we can also get rid of the following
>> code in set_rel_size():

No, we can't --- that's still reachable if somebody says
"SELECT FROM ONLY partitioned_table".

			regards, tom lane