Yes, I have cyclical references, so that is probably what is happening.
I tried setting DEFERRABLE and INITIALLY DEFERRED before, but was still
getting errors from PostgreSQL (which was very frustrating since I had
said INITIALLY DEFERRABLE but PostgreSQL was complaining about an
invalid foreign key as soon as I inserted the child record but before I
did the commit). I just went back and looked at the last case where
this was happening and saw that I did not set INITIALLY DEFERRED and
DEFERRABLE (probably because I gave up after the last time I tried).
I'll try setting these again and see what happens.
Thanks for the help!
Jeff
Andrus Adamchik wrote:
Cayenne handles correct ordering of operations automatically, based on
dependencies derived from relationships.The algorithm has a few
limitations though. It can't handle cycles (when Entity A depends on
Entity B, but also Entity B depends on Entity A). This probably also
includes entities that have relationships to the same entity (I assume
this is the case the original post was referring to).
There are few solutions:
1. (a workaround, rather than a solution) Do commit in two steps.
2. Define FK constraints in question as DEFERRABLE and INITIALLY
DEFERRED (supported by Postgres 8.*)
3. Set a custom org.objectstyle.cayenne.map.EntitySorter on the DataNode.
Andrus
On May 20, 2006, at 3:00 AM, Marcin Skladaniec wrote:
Hm. Strange. I do really complex commits, sometimes 7 or more related
records (I mean 7 levels of relationship, not seven entities),
related by many-to-many many-to-one relationships and never get those
problems. And it doesn't matter if the records are new or old. Could
you describe how you are creating objects and how do you commit them ?
Regards
Marcin
On 20/05/2006, at 4:31 PM, Tomi NA wrote:
On 5/20/06, Jeff de Vries <[EMAIL PROTECTED]> wrote:
I don't know if it is related or not, but I've also had problems in
the
past when I try to create a new parent and several child objects
related
to that parent all at once and then try to commit. The problem looks
like Cayenne is INSERTing the child records into the database first,
before the parent record, and the database complains that the children
have an invalid foreign key (and, yes, I have the ON UPDATE and ON
DELETE rules for the foreign key set to DO NOTHING and I still get the
error from PostgreSQL). To get around it I just committed the parent
first, then committed all the children.
I had the same problem, IIRC: I was very surprised that cayenne
couldn't handle such a commit, although truth be told, I can't imagine
everything that's going on under the hood of the operation that would
make implementing this feature difficult.
I would certainly love to see this fixed (if at all possible) as I
wasn't to happy to have to commit in the middle of what had to be an
atomic transaction. It'd also make the framework a lot more flexible,
e.g. enabling the user to have long inter-commit sessions with complex
data updates, if the user so desires.
t.n.a.
