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Re: Detecting inconsistencies of mapped-by declarations? Craig L Russell Thu May 07 11:01:36 2009

Hi Jörg,

On May 7, 2009, at 9:36 AM, Joerg von Frantzius wrote:

Hi,

in the XML metadata, it is possible to have multiple FCO fields, e.g.
B.a1 and B.a2, with identical mapped-by pointing to the same field of
the same related class, e.g. A.b. In effect this would theoretically
mean that the FK should be shared among different associations in the
object model. I don't think that this does make much sense.

I agree.


Also it is possible to declare two fields in two different classes, e.g.
B1.a and B2.a, with the identical mapped-by pointing to the same field
of the same related class, e.g. A.a. That would mean that in theory two FKs would have to be created for the same column, pointing to different
tables. That neither seems to make sense to me.

I agree.


Should the implementation throw an error in such situations, warning the
user of the erroneous metadata?

Yes.

Craig


Regards,
Jörg

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Craig L Russell
Architect, Sun Java Enterprise System http://db.apache.org/jdo
408 276-5638 mailto:[EMAIL PROTECTED]
P.S. A good JDO? O, Gasp!