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Date: Mon, 19 Jun 2006 14:09:53 -0700
From: Kathey Marsden <kmarsdenderby@sbcglobal.net>
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To: Derby Discussion <derby-user@db.apache.org>
Subject: Re: Self-configuring embedded Derby applications
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Rick Hillegas wrote:

>
> I would like to understand if anyone thinks that they might be 
> affected by the following issue. This issue affects customers who do 
> the following:
>
> o Run an embedded Derby application which generates its own Derby 
> properties on the fly.
>
> o In the same VM, run other JDBC applications. These other 
> applications could request Connections to DB2, Oracle, Derby, or any 
> other database.
>
> In general, we recommend against generating Derby properties on the 
> fly. This general problem is described in DERBY-1428. However, the 
> Derby mainline (slated to become release 10.2) expands this problem, 
> as described in DERBY-1429. For a workaround, see the Release Note 
> attached to DERBY-930.
>
I think  DERBY-1428 and DERBY-149 are not really related to generating 
derby.properties on the fly they are related to when Derby boots and 
when derby.system.home is recognized.  derby.system.home *has* to be set 
with a system property. Anyone who sets derby.system.home  or static 
derby properties programatically with  System.setProperty() may be 
affected if they do not have control over their calling context.  
Another driver might cause derby to be autoloaded before these 
properties are set.   Perhaps these issues would be better worded as:

"Derby can have non-deterministic behaviour when derby.system.home or 
other static properties are set with System.setProperty()"

  More common reported symptoms will  likely  be after upgrading to  
Derby 10.2 and JDK 1.6  users will report  the following systems because 
derby.system.home is not picked up properly.

-  I get XJ004.C=Database ''...'' not found.    (Derby is looking in the 
wrong place for the db)
-  There is nothing in my database.                 (create=true was on 
the url and so app created  a new db in the wrong place)
-  My database was created in the wrong place. 
-  Properties set in derby.properties  are not being picked up.

Some more info:
http://www.nabble.com/Re%3A--jira--Commented%3A-%28DERBY-930%29-Add-support-for-autoloading-of-Derby-client-drivers-p4909085.html

Kathey