From: Tom Lane <tgl@sss.pgh.pa.us>
To: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
cc: Joe Conway <mail@joeconway.com>,
        David Rowley <david.rowley@2ndquadrant.com>,
        Andreas Seltenreich <andreas.seltenreich@credativ.de>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Excessive memory usage in multi-statement queries w/ partitioning
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Comments: In-reply-to Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
	message dated "Mon, 27 May 2019 14:58:12 +0900"
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Date: Mon, 27 May 2019 08:56:29 -0400
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Amit Langote <Langote_Amit_f8@lab.ntt.co.jp> writes:
> On 2019/05/24 23:28, Tom Lane wrote:
>> So my thought, if we want to do something about this, is not "find
>> some things we can pfree at the end of planning" but "find a way
>> to use a separate context for each statement in the query string".

> Maybe like the attached?  I'm not sure if we need to likewise be concerned
> about exec_sql_string() being handed multi-query strings.

Please add this to the upcoming CF so we don't forget about it.
(I don't think there's anything very new about this behavior, so
I don't feel that we should consider it an open item for v12 ---
anyone think differently?)

			regards, tom lane