I read that one and it could be related, but this issue applies to the SQL generated during the merge() only, not during persist(). The SQL generated for inserting the record executes just fine (I didn't attach that part of the log because it was quite lengthy). That bug also seemed to be quite tied to Postgresql and this is in DB2.
I have actually been searching the forums for about 2 months about this issue thinking that someone else must have seen it. I finally duplicated this simple example and posted myself. The bug you refer to is still unconfirmed but has an attachment. Is there something I should try with the InheritancePolicy.java attachment?
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