Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.84_2) (envelope-from ) id 1crHcm-0007BR-MA for pgsql-hackers@arkaria.postgresql.org; Fri, 24 Mar 2017 05:18:56 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.84_2) (envelope-from ) id 1crHcm-0004YL-4W for pgsql-hackers@arkaria.postgresql.org; Fri, 24 Mar 2017 05:18:56 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1crHck-0004XM-Oz for pgsql-hackers@postgresql.org; Fri, 24 Mar 2017 05:18:54 +0000 Received: from out1-smtp.messagingengine.com ([66.111.4.25]) by magus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1crHcg-0001xm-Oa for pgsql-hackers@postgresql.org; Fri, 24 Mar 2017 05:18:52 +0000 Received: from compute7.internal (compute7.nyi.internal [10.202.2.47]) by mailout.nyi.internal (Postfix) with ESMTP id 4AF6520C2A; Fri, 24 Mar 2017 01:18:49 -0400 (EDT) Received: from frontend2 ([10.202.2.161]) by compute7.internal (MEProxy); Fri, 24 Mar 2017 01:18:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:in-reply-to:message-id:mime-version:references :subject:to:x-me-sender:x-me-sender:x-sasl-enc:x-sasl-enc; s= fm1; bh=cH3P6pq8BRV2H3CnXh4JtPBl4Rf0e/4rRn3TqSM5OPo=; b=PUtyBs6f PnW44TFrtUgElovNyKzeTO5nKxWIDmTHM3Anxw/encWQGnjL43yqC0X2H7SSIbeh U06dfAnl0uiEesBYV8jXXVmeCsKYXLEjm32ffcfhmeEWsRz7WMqkxFu1BjVndk6a u5NXxdPOA51wIUDLJ/SfKLA3IDJ6vlQvYQOHkGSDaYNY4dv55Srl/mV0+I/U3k/K rkjHUxvLZHyhfBP3c2Lu7lUOlXkmF49hLBzNrocYP/dEs4/vu3vYzLRGujQ+q1ZN GZ1hXHJgmHASPrGCoO+NBH7PcXBp0O1CRW1+qD//QmYKkZ8pxWC6QLD9HLbluh5X vcWXoOqBdUXx3w== X-ME-Sender: X-Sasl-enc: 7PodMA6gcQmYM9lzZVX8mSzaetod6ntm3q/LFc6rFWr9 1490332729 Received: from april.local (c-73-13-66-39.hsd1.pa.comcast.net [73.13.66.39]) by mail.messagingengine.com (Postfix) with ESMTPA id 0BE51240AE; Fri, 24 Mar 2017 01:18:49 -0400 (EDT) Subject: Re: identity columns To: Vitaly Burovoy References: <6adbacbf-73bc-dd1a-2033-63409180fd18@2ndquadrant.com> <4ef801f2-64ce-1a58-277d-d9389ae7770d@2ndquadrant.com> <1cf308b6-4f5c-05ba-cc74-0a7121603fcf@2ndquadrant.com> Cc: pgsql-hackers From: Peter Eisentraut Organization: 2ndQuadrant Message-ID: <06a416db-e35b-36d1-7e2f-0affdee24745@2ndquadrant.com> Date: Fri, 24 Mar 2017 01:18:48 -0400 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Pg-Spam-Score: -2.6 (--) 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 3/23/17 06:09, Vitaly Burovoy wrote: > I think we'll end up with "DROP IDENTITY IF EXISTS" to avoid raising > an exception and "ADD OR SET" if your grammar remains. That sounds reasonable to me. > Right. From that PoV IDENTITY also changes a default value: "SET (ADD > ... AS?) IDENTITY" works as setting a default to "nextval(...)" > whereas "DROP IDENTITY" works as setting it back to NULL. But dropping and re-adding an identity destroys state, so it's not quite the same. -- Peter Eisentraut http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers