google app engine - On GoogleEngine (Java), in JDO, how do I query a list of child objects based on the id of the parent? -
i have 2 value objects, calendar , event, persistent. calendar has property consists in list of events, 1 many relationship. calendar parent of events shown below. @persistent @element(dependent = "true") private list<event> events; now, able retrieve via jdo query, events corresponding calendar, based on calendar object key. using encodedkey both classes. i want run query on event entity , not retrieve whole calendar object, because want able retrieve set of events, pagination purposes. i tried in possible way, not figure out how query parent key. any appreciated. a few notes: list properties in entities (like list<event> events ) stored serialized protocolbuffer. problem is: if property indexed, limited 5000 elements. every time query list, whole list needs deserialized. answer question if can selectively retrieve list elements: can't. if have multiple indexed list properties in entity can lead exploding indexes . if want un...