I want to create a key for this relationship, lets say if A -> B exists, B -> A cannot exist together. I was thinking of concatenating key A and key B, sth like A-B. I make sure the smallest key is first, so that I dont have any B-As.
But, how would I do a query for the two entitites? Is the only solution to have extra ArrayList<Key> or Key from, Key to attributes and put them in the criteria? On Mon, Aug 10, 2009 at 5:08 AM, objectuser <[email protected]> wrote: > > If that's as complex as your queries get, I'd recommend just doing to > queries and merging the results. > > Also, if the semantics of fromAttribute and toAttribute are different, > then you've lost that in your second model. > > On Aug 9, 10:45 pm, Sam Walker <[email protected]> wrote: > > I have a directed graph scenario and I want to model the relationship > with > > App Engine data store. > > > > Relationship { > > Key from; > > Key to; > > boolean fromAttribute; > > boolean toAttribute; > > > > } > > > > I want to do this query: where (from = <key> and fromAttribute = > > <attribute>) or (to = <key> and toAttribute = <attribute>). Ors are not > > allowed. So, I am not sure how to do it. I am now thinking of doing: > > > > Relationship { > > ArrayList<Key> both; // Will always have two keys > > ArrayList<boolean> attributes; > > > > } > > > > Now, I could change the query to: where <key> in both, and then check for > > respective attributes, but that's kinda ugly. > > > > I am sure there will be a better way, please help. > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en -~----------~----~----~----~------~----~------~--~---
