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Date: Wed, 20 Jun 2007 23:07:52 +0200
From: "=?ISO-8859-1?Q?=D8yvind_Harboe?=" <oyvind.harboe@zylin.com>
Sender: oyvindharboe@gmail.com
To: user@cayenne.apache.org
Subject: Relationships across databases
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In the link below it says that relationships does not work across
databases "as it will require Cayenne to do in memory cartesian
product processing".

What does this qualifier mean? Does it mean that it is possible to
enable this, but it would take a lot of memory? That this feature was
considered, but rejected as it would have not worked in all cases?

For the cases that we need this, there is no problem for Cayenne to
have both tables completely in memory (always < 1000 records) so I'm
not concerned about CPU processing power or memory consumption.

Has any work been done on supporting this?


We've got a real database (Derby) that has relationships to other
existing datbases(MS Access/FoxPro databases). We can't move the
existing databases into Derby due to bug-by-bug compatibility
problems.

http://cwiki.apache.org/CAY/multiple-databases-example.html

--=20
=D8yvind Harboe
http://www.zylin.com - eCos ARM & FPGA  developer kit