I know the parent post is over a year old, but in case anyone is searching old posts:
I believe you would have to either copy the query to a new one which uses the subclass, or somehow query for the subclass discriminator column (using .class?). In other words, the caller would choose what subclass by setting the discriminator as a parameter. I'm not 100% sure if the second method works or not (I have had mixed results depending on which O-R framework and which version), but if it does work then that would be more concise than creating a whole new query. If it does not work then you could build the query dynamically passing the MySubclass.class to a DAO method.
Also, according to JPA documentation the query should be polymorphic regardless of the inheritance strategy used. Is this true?
If anyone has any input on this, please post...
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