Google app engine JDO data store design using inheritance -

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i using subtable inheritance strategy design data store using jdo application hosted in google app engine. there 3 types of users can logs app. these classes designed purpose 1) user(abstract) 2)usertype1 extends user 3) usertype2 extends user 4) usertype3 extends user. problem every time want find user based on userid have check each entity kind separatly. become more problem when user types increases. please how design model classes in scenario.

thanks

you're looking jdo2's superclass-table inheritance technique. works similar python app engine polymodel class.

unfortunately, app engine doesn't support superclass-table right now. instead, consider consolidating of different class's fields single user class type enum.


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