google app engine - Retrieve the list of friends of specific user when i select that user in appengine -

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i had 2 entities user , friends in app engine jdo in user had list of friends want when select table user retrieve entity friend list of friends associated user....how can perform in app engine ?

relation between entities python described here (i guess pretty same java): http://code.google.com/appengine/articles/modeling.html

it seems need many many relation. simplest way have list of db.key property in user model. can make sure whenever create new connection between friends, both lists of friends updated.

alternatively define function searches db users have user's key in friends list, using gql query. imho seems less organised other method.


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