Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1p4mYG-00057J-Sv for pgsql-sql@arkaria.postgresql.org; Mon, 12 Dec 2022 17:25:16 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.92) (envelope-from ) id 1p4mYF-0008Uo-Oz for pgsql-sql@arkaria.postgresql.org; Mon, 12 Dec 2022 17:25:15 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1p4mYF-0008Uf-Ex for pgsql-sql@lists.postgresql.org; Mon, 12 Dec 2022 17:25:15 +0000 Received: from mail-pj1-x102d.google.com ([2607:f8b0:4864:20::102d]) by magus.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1p4mYC-0000pd-7S for pgsql-sql@lists.postgresql.org; Mon, 12 Dec 2022 17:25:15 +0000 Received: by mail-pj1-x102d.google.com with SMTP id z8-20020a17090abd8800b00219ed30ce47so569381pjr.3 for ; Mon, 12 Dec 2022 09:25:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=hZy+Jd2ZkwUtHAI6F480EgCp5j6wmNVzJWQq+DfQqvk=; b=bJOkp9R8+KzKMIpjPUzZi07resQb7FzJ8Bgv19JLEw0yNONGljG1drfNX+BZY1fmnQ RkAOEn1igC6t17SZEO5F8HGQOZpmCGxpVXbwCFC8yNIoyLIPPL0jnCbX7h8mHW99/Q0w 4DsyhmqruIVGi4fAhugTOn1az9JY0xNP6iFyHv9+RtgFn4wvQOfGCpx7GYRf1Ll5SOCT gwJpF0D5dB+il1NxVCGCrnscS69BOZQMQF9/vLgTtHzQQRaMuTQTTmYem+lvXAdMB6qL cb7xnMLVnPbAi/bfFBIkXbYawnD2jjiTqj1BsGs+fPVKbYG7xcHQZk+LMX0+O5vZXr3o Gf1w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references: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=hZy+Jd2ZkwUtHAI6F480EgCp5j6wmNVzJWQq+DfQqvk=; b=w7/2r9T2PXPvZ0YMQkbsvrkSYCdyy4FQ4IrMFJCt3FlvlHNoqWCNo9iblmF0Lp/FHW iVKS9kshM6Bl0naGZQLmj6BNotaELh4G+OAYm2SAG0trxb206Gb6exrXBBX/1lr5mhHG fTOusZmO2AllyEVN89esyZ02Adp/mJ2Ftwb7gXpTCeRk1zLpjZgPFWJhoX4+p3e2RbZF Akz9tDBNIgsUzeDAJEgyLehWLpvKr9MVhjrQR0mbxjRHETZQwoJxZVQw0ACJwlxbfV4X aX5j8NduXF3+PXQqkF3Um0GdBJZatttEeVYDy5oSY0yQcc2sTXEBlzOOwL81tzOt1YkZ jkRQ== X-Gm-Message-State: ANoB5pkBVZsP8+B7GkyiRB2WSagVMQ7B7dcbMaBs7evo4fMqyuw+YwHJ MBppyidWI4Bc2ZH0d2wULqo8DQaMQu8= X-Google-Smtp-Source: AA0mqf5sinRPpxgMYbVY3fk1tOzos6Hjxk3MDdPgU7YtFmkco8VG32tXwljEBLCk6bPpVDxsXCEqLw== X-Received: by 2002:a17:902:f54b:b0:188:5e99:d84f with SMTP id h11-20020a170902f54b00b001885e99d84fmr24709754plf.42.1670865909739; Mon, 12 Dec 2022 09:25:09 -0800 (PST) Received: from [10.128.57.14] ([155.98.131.6]) by smtp.gmail.com with ESMTPSA id c18-20020a170902d49200b00186b69157ecsm6651301plg.202.2022.12.12.09.25.08 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 12 Dec 2022 09:25:09 -0800 (PST) Message-ID: <1e0484b6-40a6-15a9-9890-0991c8b8c1da@gmail.com> Date: Mon, 12 Dec 2022 10:25:08 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.4.2 Subject: Re: PARALLEL CTAS Content-Language: en-CA To: pgsql-sql@lists.postgresql.org References: From: Rob Sargent 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 12/12/22 10:13, Shane Borden wrote: > The issue is there are certain performance benefits to be had by doing > parallel CTAS operations and when converting from Oracle to PostgreSQL > switching to a “COPY” operation isn’t feasible. > --- > > Thanks, > Today I suspect you're left with something like the following: - CTAS from source where 1=2 (i.e. table definition via select semantics) - copy from stdin (filled with intended CTAS select)