Return-Path: Delivered-To: apmail-db-derby-user-archive@www.apache.org Received: (qmail 23502 invoked from network); 14 Oct 2008 23:01:08 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (140.211.11.2) by minotaur.apache.org with SMTP; 14 Oct 2008 23:01:08 -0000 Received: (qmail 14254 invoked by uid 500); 14 Oct 2008 23:01:09 -0000 Delivered-To: apmail-db-derby-user-archive@db.apache.org Received: (qmail 13797 invoked by uid 500); 14 Oct 2008 23:01:08 -0000 Mailing-List: contact derby-user-help@db.apache.org; run by ezmlm Precedence: bulk list-help: list-unsubscribe: List-Post: List-Id: Reply-To: "Derby Discussion" Delivered-To: mailing list derby-user@db.apache.org Received: (qmail 13786 invoked by uid 99); 14 Oct 2008 23:01:08 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 14 Oct 2008 16:01:08 -0700 X-ASF-Spam-Status: No, hits=2.7 required=10.0 tests=MSGID_FROM_MTA_HEADER,SPF_NEUTRAL X-Spam-Check-By: apache.org Received-SPF: neutral (athena.apache.org: 83.137.146.145 is neither permitted nor denied by domain of stephan@republika.nl) Received: from [83.137.146.145] (HELO mail.republika.nl) (83.137.146.145) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 14 Oct 2008 23:00:01 +0000 Message-ID: <48F52491.2090903@republika.nl> MIME-Version: 1.0 X-MessageIsInfected: false Received: from cc97655-a.groni1.gr.home.nl. ([82.73.12.75]) by mail.republika.nl (REPUBLiKA SMTP Server 1.0) with ESMTP ID 981 for ; Wed, 15 Oct 2008 01:00:34 +0200 (CEST) Date: Wed, 15 Oct 2008 01:00:33 +0200 From: "Stephan van Loendersloot (LIST)" Organization: REPUBLiKA B.V. User-Agent: Thunderbird 2.0.0.17 (Windows/20080914) To: Derby Discussion Subject: Re: Merging two Derby databases, update database structure to old one References: <48F4DC8D.4000604@phnet.fi> <48F50443.2000808@republika.nl> <48F515AE.7060105@phnet.fi> In-Reply-To: <48F515AE.7060105@phnet.fi> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Virus-Checked: Checked by ClamAV on apache.org Juho Tykk�l� wrote: > Stephan van Loendersloot (LIST) kirjoitti: >> Juho Tykk�l� wrote: >>> >>> Why I ask is: If I'm going to add more features to my software, >>> which uses Derby database, and these features need database >>> structural changes, how can I update my customer's old software >>> versions without touching the data inside their databases. Just >>> need to add few columns more and don't want to clear data inside >>> database. >> Hi Juho, >> >> You can use the same statements that you applied on your development >> database to update your customers' databases. Just be aware of common >> pitfalls when altering databases on productions systems, though. >> >> > Hi Stephan, > > > Yes, I know alter table. > > What I meant was: Is this possible by only moving and merging files > located at database/seg0/ directory? If it is, it would be much more > easier because I could update database changes among > other files using just "plain installation script" or other installer. > Hi Juho, Sorry, but that's not possible. Even if it were, then the database would have to be made aware of changes in the filesystem, or perform some sort of scanning to be able to recognize and integrate changes. Besides, files that are in use by the database may be locked by the operating system while being read from or written to.. Guess you'll have to stick to regular updates. Regards, Stephan.