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Date: Sat, 26 Feb 2011 07:56:53 -0800
From: Bryan Pendleton <bpendleton.derby@gmail.com>
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To: Derby Discussion <derby-user@db.apache.org>
Subject: Re: Access to embedded derby db
References: <31018634.post@talk.nabble.com>
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On 02/25/2011 11:43 PM, linux86 wrote:
> Can I ignore the lock on db or access to db in read only mode?

No, those techniques are likely to bring crashes and database
corruption, I'm afraid.

In general, the only way to have multiple independent Java executables
accessing the same Derby database is to channel them all through
a NetworkServer instance.

Can you control the JDBC URL used by the other program? If so,
you could point it to a Network Server URL of a server that
you controlled.

Alternatively, if you can invoke the other program from within
your own Java program (that is, if the other program is a simple
Java executable), you could start the network server from within
your own program prior to starting the other program, and then
your own super-program would be able to serve concurrent requests
from other tools as well as allowing the other program's direct
access to the DB from within your super-program.

thanks,

bryan