Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1tatDf-0066Em-2V for pgsql-hackers@arkaria.postgresql.org; Thu, 23 Jan 2025 09:09:48 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.94.2) (envelope-from ) id 1tatDe-00Cgnt-4a for pgsql-hackers@arkaria.postgresql.org; Thu, 23 Jan 2025 09:09:46 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1tatDd-00Cgnl-Rx for pgsql-hackers@lists.postgresql.org; Thu, 23 Jan 2025 09:09:45 +0000 Received: from mail.clear-code.com ([2401:2500:102:3037:153:126:203:179]) by magus.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1tatDY-0013mm-1c for pgsql-hackers@postgresql.org; Thu, 23 Jan 2025 09:09:44 +0000 Received: from localhost (unknown [IPv6:2404:7a80:9f01:f500:acd0:2aa3:7b08:7206]) by mail.clear-code.com (Postfix) with ESMTPSA id 9DCDB66DBB6; Thu, 23 Jan 2025 18:09:31 +0900 (JST) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.clear-code.com 9DCDB66DBB6 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=clear-code.com; s=default; t=1737623371; bh=QGL3SHgqa0t7w2jzx/efMoNV43qfHgCG7V3CnvqcCS4=; h=Date:To:Cc:Subject:From:In-Reply-To:References:From; b=nyyON24g29sixCA+GyXS/dlTMwoO8we7RanJDbmL9DXdV6E4GElbVrotv0H3QsLh8 cPwpmhIi/PBbmgXTDdkFf7b7OH14r0PGW6q1XD9F8qIcDmJhHGSWSfwwMTeWWpy0XI Kx2ycjvY8PsJ4ebOXrz/r9w3j+9X79de1HUEwVtk= Date: Thu, 23 Jan 2025 18:09:29 +0900 (JST) Message-Id: <20250123.180929.1687845160025621890.kou@clear-code.com> To: zhjwpku@gmail.com Cc: sawada.mshk@gmail.com, michael@paquier.xyz, pgsql-hackers@postgresql.org Subject: Re: Make COPY format extendable: Extract COPY TO format implementations From: Sutou Kouhei In-Reply-To: References: <20241129.100713.891341792145967125.kou@clear-code.com> X-Mailer: Mew version 6.8 on Emacs 29.4 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 9DCDB66DBB6 X-Rspamd-Server: mail.clear-code.com X-Spamd-Result: default: False [2.90 / 999.00]; SUSPICIOUS_RECIPS(1.50)[]; MID_CONTAINS_FROM(1.00)[]; MV_CASE(0.50)[]; MIME_GOOD(-0.10)[text/plain]; TAGGED_RCPT(0.00)[]; ARC_NA(0.00)[]; ASN(0.00)[asn:2518, ipnet:2404:7a80::/29, country:JP]; RCVD_COUNT_ZERO(0.00)[0]; MIME_TRACE(0.00)[0:+]; FREEMAIL_TO(0.00)[gmail.com]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; TO_MATCH_ENVRCPT_ALL(0.00)[]; FROM_HAS_DN(0.00)[]; FREEMAIL_CC(0.00)[gmail.com,paquier.xyz,postgresql.org]; FROM_EQ_ENVFROM(0.00)[]; TO_DN_NONE(0.00)[]; RCPT_COUNT_THREE(0.00)[4] X-Rspamd-Action: no action List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk Hi, In "Re: Make COPY format extendable: Extract COPY TO format implementations" on Fri, 29 Nov 2024 10:15:04 +0800, Junwang Zhao wrote: > This thread and [1] thread are kind of interleaved, I chose this thread > to share the numbers because I think this feature should be committed > first and then adapt the *copy to json* as a contrib module. I agree with you. > Committers on this thread seem worried about the performance > drawback, so what I tried to do is that *if 2 is slightly worse than 1, > but better than 3*, then we can commit 2 first, but I did not get > the expected number. Could you break down which patch in the v13 patch set[1] affected? If we can find which change improves performance, we can use the approach in this patch set too. [1]: https://www.postgresql.org/message-id/CACJufxH8J0uD-inukxAmd3TVwt-b-y7d7hLGSBdEdLXFGJLyDA%40mail.gmail.com Thanks, -- kou