From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 5065326717 for ; Fri, 18 Jan 2019 04:59:57 -0500 (EST) Received: from turing.freelists.org ([127.0.0.1]) by localhost (turing.freelists.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id EZyh7ED8fGis for ; Fri, 18 Jan 2019 04:59:57 -0500 (EST) Received: from smtp39.i.mail.ru (smtp39.i.mail.ru [94.100.177.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTPS id 8299026716 for ; Fri, 18 Jan 2019 04:59:56 -0500 (EST) Date: Fri, 18 Jan 2019 12:59:49 +0300 From: Kirill Yukhin Subject: [tarantool-patches] Re: [PATCH 2/2] sql: compute resulting collation for concatenation Message-ID: <20190118095949.jzvics4hkhmz6aih@tarantool.org> References: <652a9e6a4514a03ef93133961b09c2f5d45721d8.1547644180.git.korablev@tarantool.org> <20190117133322.GO28204@chai> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20190117133322.GO28204@chai> Sender: tarantool-patches-bounce@freelists.org Errors-to: tarantool-patches-bounce@freelists.org Reply-To: tarantool-patches@freelists.org List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: tarantool-patches List-subscribe: List-owner: List-post: List-archive: To: tarantool-patches@freelists.org Cc: v.shpilevoy@tarantool.org, Nikita Pettik Hello, On 17 Jan 16:33, Konstantin Osipov wrote: > * Nikita Pettik [19/01/16 17:06]: > > According to ANSI, result of concatenation operation should derive > > collation sequence from its operands. Now it is not true: result is > > always comes with no ("none") collation. > > Generally, it should be very cheap to introduce expression static > analysis phase by adding static analysis state to struct Expr. > Yes, it's a blasphemy from separation of concerns point of view > but it seems to be a lesser evil than invoking partial static > analysis here and there during code generation. I think that static analysis pass is of course very useful, but it is big volume of work. I propose to move this effort to the next release and adopt proposed solution. -- Regards, Kirill Yukhin