Actually, that's exactly what I was looking for.  I'm testing for
clustered environment with caching and without and an Oracle back end.

Have you tried using JCS for clustered caching?  I couldn't get it to
work.  Thought I might try Tangosol for it.

Jason



On Sat, 2003-04-12 at 09:12, BRIAN JOSEPH MCGOUGH wrote:
> Jason,
> 
> We ended up using the Per Transaction implementation that Thomas provided, since 
> this will avoid the circular references that are causing your problem, but further 
> allows us to run in a clustered environment without having to run a caching system 
> like ECS (which would require you to open rmi ports on your servers).
> 
> Performance goes down when not caching, but such is the cost of using a framework 
> that makes your database interaction work so much easier.
> 
> And since we are using oracle on the back end, oracle caches the prepared statements 
> that have recently been run in memory, so the overall impact is mitigated by this.
> 
> Brian McGough
> Indiana University
> Systems Integration Team
> 
> 
> From: Thomas Mahler <[EMAIL PROTECTED]>
> To: OJB Users List <[EMAIL PROTECTED]>
> Subject: [FAQ] Re: ObjectCacheEmptyImpl regurgitating
> Date: Sat Apr 12 03:35:09 EST 2003
> 
> Hi Jason,
> 
> The Problem you see is due to circular references in your data.
> Say A references B and B has a backreference to A.
> 
> Now we load A from the DB. If autoretrieve="true" for the 
> reference-descriptor describing the reference to B, OJB will also load B.
> If autoretrieve="true" for the B-reference-descriptor describing the 
> back-reference to A, OJB must retrieve A.
> And here is the key point.
> 
> If we use the defaultcache A will be in the cache already, as it was 
> loaded first. So OJB will simply lookup A from the cache. No endless 
> recursion!
> 
> But if we use the emptycache, A will not be cached. So OJB must load A 
> from the DB. And then again B is retrieved, etc., etc.
> There's you endless recursion.
> 
> In other words: A non-empty cache is needed to allow proper loading of 
> circular references. (Other O/R tools like TopLink work the same way).
> 
> If you still want to use the EmptyCacheImpl you should set 
> autoretrieve="false" and load references explicitely by 
> broker.retrieveReference(...).
> 
> cheers,
> Thomas
> 
> 
> 
> Jason McKerr wrote:
> > I just tried to turn caching off by using ObjectCacheEmptyImpl setting
> > in ObjectCacheClass, and it seems to continuously loop through the SQL
> > statement infinitely.  The default works fine though.
> > 
> > Any ideas why this might be?
> > 
> > Jason
> > 
> > 
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