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 1rAxrs-008tsn-32 for pgsql-hackers@arkaria.postgresql.org; Wed, 06 Dec 2023 19:47:36 +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 1rAxrp-00CCjX-Mt for pgsql-hackers@arkaria.postgresql.org; Wed, 06 Dec 2023 19:47:33 +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 1rAxro-00CCjP-Nw for pgsql-hackers@lists.postgresql.org; Wed, 06 Dec 2023 19:47:33 +0000 Received: from mail-yb1-xb30.google.com ([2607:f8b0:4864:20::b30]) by magus.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94.2) (envelope-from ) id 1rAxrj-00ARJs-Re for pgsql-hackers@postgresql.org; Wed, 06 Dec 2023 19:47:31 +0000 Received: by mail-yb1-xb30.google.com with SMTP id 3f1490d57ef6-da819902678so181328276.1 for ; Wed, 06 Dec 2023 11:47:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joeconway.com; s=google; t=1701892046; x=1702496846; darn=postgresql.org; h=content-transfer-encoding:in-reply-to:autocrypt:from:references:cc :to:content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=ggq8zX6TjCyhXUsBOECnQzknpzCMkhCFGJ2heU+89wg=; b=rCam2rhf6Q4pVd8jgmRc/HKmeUpZrrBLEgOLcgryjKuy5Kh/BavAD4LMQcPX2JszNj a2xJXRpViYgf5KoVR+gZkcjOJ5uBV1HnO44YSX4nXREZcw8TeW0QCNx4Vr73rrkraJaE aDeHPStpd2ikiksioN4M/TMisXYnbU9l568L4iSjWoip0wc4eVLZXyoih6OaSUUGfAaw VPa9FmUETx89ks2mPWWBmdhikblAKy9u3g6B5dxlNvT2y0haPp6caBhgMuY0rrFJbPo4 bXr8ydfh/gfQ4EnCAdU1xVlwThM476Y06Pe8wTwGOt2v2va+0SywoiPyQB1rMiXb+Q5E jIug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1701892046; x=1702496846; h=content-transfer-encoding:in-reply-to:autocrypt:from:references:cc :to:content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=ggq8zX6TjCyhXUsBOECnQzknpzCMkhCFGJ2heU+89wg=; b=eB0lK/G74qSbCcqXwGBDyEyRvnU4woTLxDUGxokfkJ6eyV41IspdSST8mmeoBc1/9A 0pe79JvICR04Pr00ukbVopj212pbwaVllFvepEcEMBjINjU5ymRlljNHek+tOSBo7QLQ yn8nH1MqU7xVcZ85rYlA9yiFqutehRvll9jFYLGDs3cUVN9JGxi7sgKL/cfYjzP1WJeg 4DByyrf5B2LUFdAeb+CG03Dzrx9LtQKPwCQz13iqa8LPp7E1LmH37sWRf6MMtOziQmUE SJ4sknieH0wbjmJqs5cFozQ3FlCl/O9vtAXx3KyspeM1CfQLZQxPOGDvPd23+L12BrmU Rsig== X-Gm-Message-State: AOJu0YwTHv4AJ0CQK7bT3r5O1Ve+L//V6SZlJ3QNSa59aQ2meRrQkeU3 8la6Kutd3My8GmxTP90xlbbeNuyssh7m/c30RIU= X-Google-Smtp-Source: AGHT+IG40Sm9mPkvZUC5VmW0yupS//rrByLvyNwv/jL2uf7XOXsgZrwWAMTJNEMz8/GPqCJC7SL1Zw== X-Received: by 2002:a25:bcc9:0:b0:db5:45e0:2fe5 with SMTP id l9-20020a25bcc9000000b00db545e02fe5mr1417864ybm.19.1701892046141; Wed, 06 Dec 2023 11:47:26 -0800 (PST) Received: from [192.168.4.41] (162-239-31-113.lightspeed.dybhfl.sbcglobal.net. [162.239.31.113]) by smtp.gmail.com with ESMTPSA id w67-20020a253046000000b00db3fca90d6esm4067719ybw.2.2023.12.06.11.47.25 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 06 Dec 2023 11:47:25 -0800 (PST) Message-ID: Date: Wed, 6 Dec 2023 14:47:25 -0500 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: Emitting JSON to file using COPY TO Content-Language: en-US To: Daniel Verite , Andrew Dunstan Cc: Davin Shearer , PostgreSQL-development References: From: Joe Conway Autocrypt: addr=mail@joeconway.com; keydata= xsFNBEpXMCsBEADDnXUQzjlyi/cX02Gtdy2CLcroE5CsC7DJKdOBDbfgn0kfiIYoV5JniG4l VyzZUodY8yUAagqLYolh0UkBzs9N+qkm7erde4ypw3jzVQ37BuzIvk3nMUbuDZDgxWqX+nVS sKc+BQ5BpzgCHg48leoRO2ohjvYnUhgH3j2rFZCzaj6qQ7mv+XoxOJmUlVQtG06Jwkk7Vu14 7U9nMMM6hyUKzVnmCphnlcMNo26UyVU70MwFfFJgcI0c5fpp8byN56eD6VJVnufO5WAuEhzE qcrSJR2FAlmM90GBY+6vP29twLDCHuSFvrnujNCx/BvCC/a3/gPvyAFp4JtMm9eXAmq3m/Kw 94nTJXVdcbQeQQDp3KIG7MmWS4lnGvPn8v0CjgNaLvZXFLo1FgmUVsyEq1Lww4iRLa6sbpXJ ESx15UEue1k1YZM9C+4F/o3aeKNsAienjw2EXFzcaxIg/C4P493VMi3Qa8ycVxR5iYhUbYdo DFIUQhbFNsYfrtW/qZAELT3FCYFpZYG01e9Hj+cBrXXgyDDkQ5Lq4mlvmkRvuxn61V6Au4HA 0sJiCox5pM1FvzT+aI8HY1BYaiB9Pl4fhpKgmhhlSuglk9v39S4jmlUIb45iLAUVpeNM6Qjm 69pf5da9sm4aGFa7YlDSKf/WcU7z9ITZxsilOi2n7YJiwG7kTQARAQABzSRKb3NlcGggRSBD b253YXkgPG1haWxAam9lY29ud2F5LmNvbT7CwXoEEwEIACQCGwMCHgECF4AFCwkIBwMFFQoJ CAsFFgIDAQAFAlWTVvUCGQEACgkQMyt+aLaZQ0oPCQ/9HyRewMyvAIJRmoXoLAr8AoFLId6R qBJnNX0Lll0RLZui65aQ0+exwX7aH7TxWR16B2gWX3OmLfGT8XITOoG+zt9zsEpLvNkHchkF T/jyAcbuRj5WX9hamZgMbjXAJeCdlhW+fRA9Upb0w4dgBjqK5OgsqMikASL7t2vogHl9H08j vSoQLW+8wTnSBXBeBTBwB7xLIin5WVivzFHUCrnD2UsjeBIW3fmGdpTAjSxRzG+UPYVwXQ8F FLt7DpEytvLWapmZWMRdj0WZ/Q3SOO/Ed0yFqbzuwKaWcFrQBNeS2Sig+FefBNS98f9Hx7ku H3DW34qX/zSSdDh0jLs7X3PkIgF6BZR2TxaCwHPP9ERDiDaUInC9U7We1iZE1DjW8rLMEVJB hY0ClrrF67pnUKTbcU+uajpPn+2Jl74T0Set/XxpHZ4cezcJuqg31R8vHZgd5cf1WKP0D0pc qiuS02BBFkNCs1jQ+raTWcDuE6F1mUO2nvjUBN9r4y5DUbCNSqLKeAe/aA6JaSDkBpoXKdNS +c4rbzbktWkfUW8EhVlCGzNpy4ezEoVsqV2Ex7fNoxsE2vnSylLT9hycAmYf8ryMvniRZqnD T4JgLenIcQlkhB896T7wApOXfD8OJj1/XFxAfPi6vdlsr81uoxuB4euLp8IyduwLORRUogO9 zmAXG5jOwU0ESlcyJwEQAOkTBb9yDhJbMUgvhM11rZwT5tm4Y9TqtEHn0Zy3t9g7bdFFpMva v/KENd3oAtLFpMDf+H3AggFk4ftUwJwiVgJ88ilvCynJUGXiuYIaexY4DLgn4xpnuiEpYEFV dWnlw7dWVTc62exfqIz9bSWRzwfBCY9ruYGEb4RDPDSNSAVyI7sxHzef2asiYxIcxrTrw5Vu gWNlPZcV5/EJ6PUvATjBF2TBkXV7KOciQng2tsQGrGMkY5mduNqwpuh6zfPcVF8LeObe96wv 5ZhPRpO79nef7hnK2lJogp3JIo558Jlbz9WHtQEMZR85+bUhtI825QyNAFz3Jrn7NMgvDikc 2OrWo7YMgMC5hDSWVFqA6/EQCNnDWGABWgeYHZFpnPwsvUWIYdhSilUuj/Tuzvz9ZmucFNbQ bauDQw6VQ38ofGnoYDZFJsGncprB8dBi4tDrIQ+1RlIh6C2Z/eMipqJOT26+spluTjouvnKT 0S5yOgyX0PjbsysgwQdCGNJLHOjhHbSpSmOLaduV3CQo/0+DHT/TBjYfIXjTWouY9TkGxG4e NrxU0u2xAy5bMqOPmsFdjLTWlQUlF/fTMhB54XwI3FHWgnSnXZzStDTmTebLNdT/ftgliAzA 81uMj49j0exv731/v+7udLA1bV8gnZ01zQCASDpWiRQR3fgwcugSUqgRABEBAAHCwV8EGAEI AAkFAkpXMicCGwwACgkQMyt+aLaZQ0pwAQ//bjcWnZg/jjRQ9gbZUGMqniItZYRglBMKIqt4 Fia379JmHwTvavnFkJ8XMZ56UB0FIrgS+sUkRH6cPRQR+7Qi392LD021DXgSsz9CwFHjFyBG HwLEOTRcfYQbtJy0shHDJB4aQTOX3ERDH1PsvJNuevmQMzS0DWFav9+xMz9rKP4N+HffoBIZ E0C1xIE43nD4eLsbycte9sVIrmlNuUti3qUxJAQw8HwfJ6ZbBInHxquApR16uD1u99o6Xlnd FrDlY22tRmHCM0bR81GfGNdcU3Uo+rG/R/k4qa7s9/dgKvMbyH3fHhp/ceKag80Xo8IFurRl 0ZJP3sHJ2QDHCVLat7jRZ+43hi1WlIhFbrgn6IyI0i7XR/W8JjrC5MsKq4TUwGH077sU/kcH YebVJZRbUUst2hAGHDFVBcG12qoKf+ltL9qXJc1y7BGeCoUW6QjOpljpq6ZL4FQUsM0RSRjs 5egE3szPcIf5SyPK6WDOApoAq6M7BBFMGDZwEylYMtr0YekA1u86UA9D2xwLHEbBBp/uiby1 c9JbPJ1Pn8zJP8WZNeRw4Q9TtqVK09+oLirMUSpIDd6KdZ1VgRxOK2re7tjDvkVuYsSrsiJ+ 1iJNEnp9iK0ok0DlJpSCe6KhkxpaTdeoWMXdKuJWec0NIqoAd54ZgBPnr+UPxTixgPq/p6Q= In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk On 12/6/23 13:59, Daniel Verite wrote: > Andrew Dunstan wrote: > >> IMNSHO, we should produce either a single JSON >> document (the ARRAY case) or a series of JSON documents, one per row >> (the LINES case). > > "COPY Operations" in the doc says: > > " The backend sends a CopyOutResponse message to the frontend, followed > by zero or more CopyData messages (always one per row), followed by > CopyDone". > > In the ARRAY case, the first messages with the copyjsontest > regression test look like this (tshark output): > > PostgreSQL > Type: CopyOut response > Length: 13 > Format: Text (0) > Columns: 3 > Format: Text (0) > PostgreSQL > Type: Copy data > Length: 6 > Copy data: 5b0a > PostgreSQL > Type: Copy data > Length: 76 > Copy data: > 207b226964223a312c226631223a226c696e652077697468205c2220696e2069743a2031… > > The first Copy data message with contents "5b0a" does not qualify > as a row of data with 3 columns as advertised in the CopyOut > message. Isn't that a problem? Is it a real problem, or just a bit of documentation change that I missed? Anything receiving this and looking for a json array should know how to assemble the data correctly despite the extra CopyData messages. -- Joe Conway PostgreSQL Contributors Team RDS Open Source Databases Amazon Web Services: https://aws.amazon.com