On Sep 23, 2008, at 7:58 AM, [EMAIL PROTECTED] wrote:
>
> hi
> i cant get how to configure cascades over many-to-many relations.
> in my case these are implicit m2m (via secondary-table), being treated
> as either versioned one2many, or versioned many2one.
>
> lets say there is versioned A having many versioned Bs.
> (' and " denote version number):
> A1' has B1 which has versions:
> A1'.bs = [B1', B2']
> (another timestamp)
> A1'.bs = [B1", B2']
> A2 has versions which keep same B2, one has also B3:
> A2'.bs = [B2']
> (another timestamp)
> A2".bs = [B2', B3']
>
> deleting A1' should delete B1' and B1"
> deleting A2' should not delete B2'; only deleting all A2' and A2" and
> A1' should delete B2'.
> is this "all,delete-orphan" given to the A.relation(B) ?
> or only "delete-orphan"?
> how about backrefs (if any)
delete-orphan pretty much needs delete to work correctly. but for the
many-to-many use case, I'm not sure if SQLA does "the right thing" and
cross references every relationship - these cascades were designed
more for the o2m direction (I think Hibernate supports them only for
o2m relations). I'd work up some simple test cases to see what it
has to say in this regard (it would have to actively load in other
objects to see if an object is truly an "orphan", for example. not
sure if its going to try that).
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