Return-Path: Delivered-To: apmail-db-derby-dev-archive@www.apache.org Received: (qmail 94144 invoked from network); 19 Jun 2006 22:45:31 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (209.237.227.199) by minotaur.apache.org with SMTP; 19 Jun 2006 22:45:31 -0000 Received: (qmail 11412 invoked by uid 500); 19 Jun 2006 22:45:30 -0000 Delivered-To: apmail-db-derby-dev-archive@db.apache.org Received: (qmail 11386 invoked by uid 500); 19 Jun 2006 22:45:30 -0000 Mailing-List: contact derby-dev-help@db.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: Delivered-To: mailing list derby-dev@db.apache.org Received: (qmail 11373 invoked by uid 99); 19 Jun 2006 22:45:30 -0000 Received: from asf.osuosl.org (HELO asf.osuosl.org) (140.211.166.49) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 19 Jun 2006 15:45:30 -0700 X-ASF-Spam-Status: No, hits=-0.0 required=10.0 tests=SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (asf.osuosl.org: domain of jta@bristowhill.com designates 66.75.162.136 as permitted sender) Received: from [66.75.162.136] (HELO ms-smtp-04.socal.rr.com) (66.75.162.136) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 19 Jun 2006 15:45:29 -0700 Received: from [192.168.15.53] (cpe-204-210-23-212.san.res.rr.com [204.210.23.212]) by ms-smtp-04.socal.rr.com (8.13.6/8.13.6) with ESMTP id k5JMj3N9024018 for ; Mon, 19 Jun 2006 15:45:08 -0700 (PDT) Message-ID: <449728EF.9080009@bristowhill.com> Date: Mon, 19 Jun 2006 15:45:03 -0700 From: "Jean T. Anderson" Reply-To: jta@bristowhill.com User-Agent: Mozilla Thunderbird 1.0.7-1.1.fc3 (X11/20050929) X-Accept-Language: en-us, en MIME-Version: 1.0 To: derby-dev@db.apache.org Subject: Re: Driver autoloading and engine booting References: <44933535.8050801@sun.com> <449336BF.8060300@sun.com> <44941956.3050405@sbcglobal.net> <4496D513.3060504@sun.com> <4496DB21.3000003@bristowhill.com> <4496F9EB.5030009@sun.com> <449704AA.1020001@bristowhill.com> In-Reply-To: <449704AA.1020001@bristowhill.com> X-Enigmail-Version: 0.93.0.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Virus-Scanned: Symantec AntiVirus Scan Engine X-Virus-Checked: Checked by ClamAV on apache.org X-Spam-Rating: minotaur.apache.org 1.6.2 0/1000/N Jean T. Anderson wrote: > Rick Hillegas wrote: >>Jean T. Anderson wrote: >>>Rick Hillegas wrote: > ... >>>Does the "precedence for properties" documentation need to be updated to >>>mention jdbc 4/jdk 1.6 behavior? >>> >>>http://db.apache.org/derby/docs/dev/tuning/ctunsetprop23308.html > >>I don't see that the precedence of properties has changed. What has >>changed is when we read properties during the lifetime of a vm. >> >>Driver-autoloading does require many other edits to the user guides. >>They are summarized in DERBY-1271. > > ok, good, thanks for the clarification. I take the "ok" back based on Kathey's post to derby-user [1]. The actual precedence for a static variable will be whatever was visible when another driver caused derby to be autoloaded, possibly before the application set that property. Kathey's derby.system.home example is probably the most likely confusion to occur. Let's say my application connects to MySQL to migrate a database to Derby. When I connect to that MySQL database, the embedded derby driver gets loaded and the embedded engine gets booted. Later, my application calls System.setProperty("derby.system.home", "/home/jta/DerbyDatabases") and creates the new derby database. But it doesn't get created where I expected -- the derby.system.home I set is ignored because the derby engine was already booted. -jean [1] http://mail-archives.apache.org/mod_mbox/db-derby-user/200606.mbox/%3c449712A1.8090507@sbcglobal.net%3e