Re: Loosing references to foreign objects -> update will fail

[Andrus Adamchik]

Good to know that it worked - I will commit it to 1.2 and 2.0  
branches. Here is the contents of the patch:

http://tinyurl.com/sz7fw
In short it prevents incomplete snapshots (those that contain only PK  
columns and no other data) from being stored in the shared cache.  
There were other safeguards against it, but obviously they weren't  
working under certain circumstances.

Andrus


On Dec 21, 2006, at 10:15 AM, [EMAIL PROTECTED] wrote:

Hi Andrus,

so your patched jar works for us in this case. The error doesn't  
occure any
more.

So first question.

What do you have changed, because we also tried the 1.2.1 version?

Thanks florian





             Andrus Adamchik
             <[EMAIL PROTECTED]
              
le.org>                                                    An
                                         cayenne- 
[EMAIL PROTECTED]
             21.12.2006  
07:38                                        Kopie

                                                                     T 
hema
              Bitte antworten            Re: Loosing references to  
foreign
                    an                   objects -> update will fail
             [EMAIL PROTECTED]
             bator.apache.org








I wonder if that's another consequence of this bug:

http://issues.apache.org/cayenne/browse/CAY-724

I implemented a fix that works in my application, but I still don't
fully understand the underlying cause of it. Still it looks like a
suspect here too. Anyways, here is a patched 1.2 jar file that I
uploaded here:

http://people.apache.org/~aadamchik/cayenne-1.2-patchCAY-724/

Try that first and let me know if it worked. If it doesn't, next
thing to check is the value of "Max Number of Objects" for the
DataDomain in the Modeler (default is 10000). You may try to increase
it to something higher.

Andrus



On Dec 20, 2006, at 5:52 PM, [EMAIL PROTECTED] wrote:
Hallo,

in our application we loose sometimes the reference to a mandatory
foreign
object (not null, foreign key)

Our object relation are

Export Container -> products
product -> client
product -> image
product -> state

The problem occurs in our exporter process. It works like

   Begin Transaction
   Select all products that are in the correct state
   Create the export container
   export all product information including the image blob to file
(read
   the objects into the memory)
   change the export container content
   for each product create the following state of the process
(update of
   the product row and create a new state row)
   commit Transaction

During the commit some of the products have no reference to a client
object. => Update will fail because no mandatory object reference
exist.
(org.objectstyle.cayenne.validation.ValidatiionException
Product.client:
"client" is required.)
The database contains the correct client relation.
So it will run correct if we reduce the max. exported products to
100. But
for a other run with other data we exported 500 products per export
run.

Also we have attached to the running process and so we see no memory
problem, because it occure if we have around 300 MB free memory in
the jvm.

For a test run we also changed the implementation. So step 6 will
also make
a commit for each product update :-(.
The result is that we can export the first 480 products, than we
got the
error. Than we have additional product in the correct state to
export. So
we will export in the example 180 and after 176 we got an additonal
error.
Afterwards we export the last 4 without a problem.

So for us it seems that we loose during the processing the
references of
some of out products. The corrupt products hat the persistent state 3
(Commited) and after the change state 4 (Modified). The persistent
state
seems for us okay.

Our Environment:
      Windows XP
      Oracle
      Cayenne 1.2
      Jboss
      Jdk 1.5.0.5

thanks

florian