Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1YsWjU-0007d9-DK for pgsql-hackers@arkaria.postgresql.org; Wed, 13 May 2015 13:29:56 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.80) (envelope-from ) id 1YsWjT-0005yF-Mg for pgsql-hackers@arkaria.postgresql.org; Wed, 13 May 2015 13:29:55 +0000 Received: from makus.postgresql.org ([2001:4800:1501:1::229]) by malur.postgresql.org with esmtps (TLS1.2:RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1YsWjR-0005vi-MW for pgsql-hackers@postgresql.org; Wed, 13 May 2015 13:29:53 +0000 Received: from mail-qg0-x233.google.com ([2607:f8b0:400d:c04::233]) by makus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.84) (envelope-from ) id 1YsWjO-0008TB-PA for pgsql-hackers@postgresql.org; Wed, 13 May 2015 13:29:52 +0000 Received: by qgeb100 with SMTP id b100so21087501qge.3 for ; Wed, 13 May 2015 06:29:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=ktzgl9cAMZ2ficPytbyWZOXdFy8GuAKKuO/ATdmErt4=; b=PBcGGWFV9erdSc3KHVF50rcYshkJrVNScI5J9E1xepqWcyM8FfeMZWNCiptRhx1J6W FVnjZkjWuvhSW60M7BsTYjT2LeuubhrZwqnJyQtu0tks3tWnN6nfAyUlmKve8IOa+WFv UEVTAaiGE1C8JKgwxKhZOdn1A2V6VBpOz4sgpjtzNEoZiaxsjuRE42xQc2adHlQ4HHHb EVDKrZuNN8vTBYV4wCZefc9ko6goBW4MVtIYtgKP/W733XPHnxln23stiBkiaMvnUpv4 9A9BSgnuBUGKWY4Aj5HI7rW0L4lDqMlpuylHQxiMjui+LwZw3BagYGecv8n1shCR705b ElIA== MIME-Version: 1.0 X-Received: by 10.140.146.129 with SMTP id 123mr28022915qhs.50.1431523789826; Wed, 13 May 2015 06:29:49 -0700 (PDT) Received: by 10.140.250.139 with HTTP; Wed, 13 May 2015 06:29:49 -0700 (PDT) In-Reply-To: <55534930.4040905@iki.fi> References: <548AF1CB.80702@vmware.com> <689EB259-44C2-4820-B901-4F6B1C55A1E4@simply.name> <549083D6.1000301@vmware.com> <54949108.3030109@vmware.com> <552FA38F.9060005@iki.fi> <5535FE71.1010905@iki.fi> <55362CAD.2000207@iki.fi> <553741FE.1080403@iki.fi> <554CB84E.3070406@iki.fi> <5550D20D.6090703@iki.fi> <55534930.4040905@iki.fi> Date: Wed, 13 May 2015 09:29:49 -0400 Message-ID: Subject: Re: Streaming replication and WAL archive interactions From: Robert Haas To: hlinnaka Cc: Michael Paquier , Venkata Balaji N , Andres Freund , Fujii Masao , Borodin Vladimir , PostgreSQL-development Content-Type: text/plain; charset=UTF-8 X-Pg-Spam-Score: -2.7 (--) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-hackers Precedence: bulk Sender: pgsql-hackers-owner@postgresql.org On Wed, May 13, 2015 at 8:53 AM, Heikki Linnakangas wrote: > Our manual says that archive_command should refuse to overwrite an existing > file. But to work-around the double-archival problem, where the same file is > archived twice, it would be even better if it would simply return success if > the file exists, *and has identical contents*. I don't know how to code that > logic in a simple one-liner though. This is why we really, really need that pg_copy command that was proposed a while back. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers